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* [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry
@ 2019-02-08 12:52 Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 01/16] powerpc: CONFIG_THREAD_INFO_IN_TASK series Christophe Leroy
                   ` (15 more replies)
  0 siblings, 16 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

The purpose of this series is to implement a fast syscall entry
on ppc32.

Unlike all other exceptions which can happen at any time and
require to preserve all registers, the syscalls do not
require the preservation of volatile registers (except LR).

Syscall entries can then be optimised with lighter entry code
than the general exception handling.

In the meantime this series refactorises the exception entry on
40x/6xx/8xx as they are pretty similar, and it takes benh series
on rationalise the settings of MSR_EE at exceptions/syscall entries
as this change pretty simplies exception entries.

On a 8xx, this series improves null_syscall selftest by 17%
On a 83xx, this series improves null_syscall selftest by 12,5%

Christophe Leroy (16):
  powerpc: CONFIG_THREAD_INFO_IN_TASK series
  powerpc/32: Refactor EXCEPTION entry macros for head_8xx.S and
    head_32.S
  powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it
  powerpc/32: make the 6xx/8xx EXC_XFER_TEMPLATE() similar to the
    40x/booke one
  powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG
  powerpc/40x: add exception frame marker
  powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG
  powerpc/40x: Refactor exception entry macros by using head_32.h
  powerpc/fsl_booke: ensure SPEFloatingPointException() reenables
    interrupts
  powerpc/32: enter syscall with MSR_EE inconditionaly set
  powerpc/32: Enter exceptions with MSR_EE unset
  powerpc/32: get rid of COPY_EE in exception entry
  powerpc: Fix 32-bit handling of MSR_EE on exceptions
  powerpc/32: implement fast entry for syscalls on non BOOKE
  powerpc/32: Remove MSR_PR test when returning from syscall
  powerpc/32: don't do syscall stuff in transfer_to_handler on non BOOKE

 arch/powerpc/Kconfig                           |   1 +
 arch/powerpc/Makefile                          |   7 +
 arch/powerpc/include/asm/asm-prototypes.h      |   4 +-
 arch/powerpc/include/asm/book3s/64/mmu-hash.h  |   2 +-
 arch/powerpc/include/asm/exception-64s.h       |   4 +-
 arch/powerpc/include/asm/irq.h                 |  18 +-
 arch/powerpc/include/asm/livepatch.h           |   7 +-
 arch/powerpc/include/asm/processor.h           | 105 +---------
 arch/powerpc/include/asm/ptrace.h              |   2 +-
 arch/powerpc/include/asm/reg.h                 |   2 +-
 arch/powerpc/include/asm/smp.h                 |  17 +-
 arch/powerpc/include/asm/task_size_32.h        |  21 ++
 arch/powerpc/include/asm/task_size_64.h        |  79 ++++++++
 arch/powerpc/include/asm/thread_info.h         |  19 --
 arch/powerpc/kernel/asm-offsets.c              |  12 +-
 arch/powerpc/kernel/entry_32.S                 | 261 ++++++++++++++-----------
 arch/powerpc/kernel/entry_64.S                 |  12 +-
 arch/powerpc/kernel/epapr_hcalls.S             |   5 +-
 arch/powerpc/kernel/exceptions-64e.S           |  13 +-
 arch/powerpc/kernel/exceptions-64s.S           |   2 +-
 arch/powerpc/kernel/head_32.S                  | 182 ++++-------------
 arch/powerpc/kernel/head_32.h                  | 203 +++++++++++++++++++
 arch/powerpc/kernel/head_40x.S                 | 154 ++++-----------
 arch/powerpc/kernel/head_44x.S                 |  16 +-
 arch/powerpc/kernel/head_64.S                  |   1 +
 arch/powerpc/kernel/head_8xx.S                 | 133 ++-----------
 arch/powerpc/kernel/head_booke.h               |  44 ++---
 arch/powerpc/kernel/head_fsl_booke.S           |  44 ++---
 arch/powerpc/kernel/idle_6xx.S                 |   8 +-
 arch/powerpc/kernel/idle_book3e.S              |   2 +-
 arch/powerpc/kernel/idle_e500.S                |   8 +-
 arch/powerpc/kernel/idle_power4.S              |   2 +-
 arch/powerpc/kernel/irq.c                      | 114 ++---------
 arch/powerpc/kernel/kgdb.c                     |  28 ---
 arch/powerpc/kernel/machine_kexec_64.c         |   6 +-
 arch/powerpc/kernel/misc_32.S                  |  17 +-
 arch/powerpc/kernel/process.c                  |  63 +++---
 arch/powerpc/kernel/setup-common.c             |   2 +-
 arch/powerpc/kernel/setup_32.c                 |  26 ++-
 arch/powerpc/kernel/setup_64.c                 |  51 +----
 arch/powerpc/kernel/smp.c                      |  16 +-
 arch/powerpc/kernel/stacktrace.c               |  29 ++-
 arch/powerpc/kernel/trace/ftrace_64_mprofile.S |   6 +-
 arch/powerpc/kernel/traps.c                    |   8 +
 arch/powerpc/kvm/book3s_hv_hmi.c               |   1 +
 arch/powerpc/mm/hash_low_32.S                  |  14 +-
 arch/powerpc/net/bpf_jit32.h                   |   5 +-
 arch/powerpc/sysdev/6xx-suspend.S              |   5 +-
 arch/powerpc/xmon/xmon.c                       |   2 +-
 49 files changed, 816 insertions(+), 967 deletions(-)
 create mode 100644 arch/powerpc/include/asm/task_size_32.h
 create mode 100644 arch/powerpc/include/asm/task_size_64.h
 create mode 100644 arch/powerpc/kernel/head_32.h

-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 01/16] powerpc: CONFIG_THREAD_INFO_IN_TASK series
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 02/16] powerpc/32: Refactor EXCEPTION entry macros for head_8xx.S and head_32.S Christophe Leroy
                   ` (14 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

This patch is a squashed version of the
CONFIG_THREAD_INFO_IN_TASK series to make building robots
happy until that serie appears in powerpc/next.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/Kconfig                           |   1 +
 arch/powerpc/Makefile                          |   7 ++
 arch/powerpc/include/asm/asm-prototypes.h      |   4 +-
 arch/powerpc/include/asm/book3s/64/mmu-hash.h  |   2 +-
 arch/powerpc/include/asm/exception-64s.h       |   4 +-
 arch/powerpc/include/asm/irq.h                 |  18 ++--
 arch/powerpc/include/asm/livepatch.h           |   7 +-
 arch/powerpc/include/asm/processor.h           | 105 ++---------------------
 arch/powerpc/include/asm/ptrace.h              |   2 +-
 arch/powerpc/include/asm/reg.h                 |   2 +-
 arch/powerpc/include/asm/smp.h                 |  17 +++-
 arch/powerpc/include/asm/task_size_32.h        |  21 +++++
 arch/powerpc/include/asm/task_size_64.h        |  79 +++++++++++++++++
 arch/powerpc/include/asm/thread_info.h         |  19 -----
 arch/powerpc/kernel/asm-offsets.c              |  12 ++-
 arch/powerpc/kernel/entry_32.S                 |  80 ++++++-----------
 arch/powerpc/kernel/entry_64.S                 |  12 +--
 arch/powerpc/kernel/epapr_hcalls.S             |   5 +-
 arch/powerpc/kernel/exceptions-64e.S           |  13 +--
 arch/powerpc/kernel/exceptions-64s.S           |   2 +-
 arch/powerpc/kernel/head_32.S                  |  14 +--
 arch/powerpc/kernel/head_40x.S                 |   4 +-
 arch/powerpc/kernel/head_44x.S                 |   8 +-
 arch/powerpc/kernel/head_64.S                  |   1 +
 arch/powerpc/kernel/head_8xx.S                 |   2 +-
 arch/powerpc/kernel/head_booke.h               |  12 +--
 arch/powerpc/kernel/head_fsl_booke.S           |  16 ++--
 arch/powerpc/kernel/idle_6xx.S                 |   8 +-
 arch/powerpc/kernel/idle_book3e.S              |   2 +-
 arch/powerpc/kernel/idle_e500.S                |   8 +-
 arch/powerpc/kernel/idle_power4.S              |   2 +-
 arch/powerpc/kernel/irq.c                      | 114 +++----------------------
 arch/powerpc/kernel/kgdb.c                     |  28 ------
 arch/powerpc/kernel/machine_kexec_64.c         |   6 +-
 arch/powerpc/kernel/misc_32.S                  |  17 ++--
 arch/powerpc/kernel/process.c                  |  63 ++++++++------
 arch/powerpc/kernel/setup-common.c             |   2 +-
 arch/powerpc/kernel/setup_32.c                 |  26 +++---
 arch/powerpc/kernel/setup_64.c                 |  51 +++--------
 arch/powerpc/kernel/smp.c                      |  16 ++--
 arch/powerpc/kernel/stacktrace.c               |  29 ++++++-
 arch/powerpc/kernel/trace/ftrace_64_mprofile.S |   6 +-
 arch/powerpc/kvm/book3s_hv_hmi.c               |   1 +
 arch/powerpc/mm/hash_low_32.S                  |  14 ++-
 arch/powerpc/net/bpf_jit32.h                   |   5 +-
 arch/powerpc/sysdev/6xx-suspend.S              |   5 +-
 arch/powerpc/xmon/xmon.c                       |   2 +-
 47 files changed, 367 insertions(+), 507 deletions(-)
 create mode 100644 arch/powerpc/include/asm/task_size_32.h
 create mode 100644 arch/powerpc/include/asm/task_size_64.h

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 08908219fba9..3f237ffa0649 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -241,6 +241,7 @@ config PPC
 	select RTC_LIB
 	select SPARSE_IRQ
 	select SYSCTL_EXCEPTION_TRACE
+	select THREAD_INFO_IN_TASK
 	select VIRT_TO_BUS			if !PPC64
 	#
 	# Please keep this list sorted alphabetically.
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index ac033341ed55..7de49889bd5d 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -427,6 +427,13 @@ else
 endif
 endif
 
+ifdef CONFIG_SMP
+prepare: task_cpu_prepare
+
+task_cpu_prepare: prepare0
+	$(eval KBUILD_CFLAGS += -D_TASK_CPU=$(shell awk '{if ($$2 == "TASK_CPU") print $$3;}' include/generated/asm-offsets.h))
+endif
+
 # Check toolchain versions:
 # - gcc-4.6 is the minimum kernel-wide version so nothing required.
 checkbin:
diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index 1d911f68a23b..1484df6779ab 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -23,8 +23,8 @@
 #include <uapi/asm/ucontext.h>
 
 /* SMP */
-extern struct thread_info *current_set[NR_CPUS];
-extern struct thread_info *secondary_ti;
+extern struct task_struct *current_set[NR_CPUS];
+extern struct task_struct *secondary_current;
 void start_secondary(void *unused);
 
 /* kexec */
diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
index 12e522807f9f..a28a28079edb 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
@@ -23,7 +23,7 @@
  */
 #include <asm/book3s/64/pgtable.h>
 #include <asm/bug.h>
-#include <asm/processor.h>
+#include <asm/task_size_64.h>
 #include <asm/cpu_has_feature.h>
 
 /*
diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h
index 3b4767ed3ec5..f0f0ff192e87 100644
--- a/arch/powerpc/include/asm/exception-64s.h
+++ b/arch/powerpc/include/asm/exception-64s.h
@@ -671,7 +671,7 @@ END_FTR_SECTION_NESTED(ftr,ftr,943)
 
 #define RUNLATCH_ON				\
 BEGIN_FTR_SECTION				\
-	CURRENT_THREAD_INFO(r3, r1);		\
+	ld	r3, PACA_CURRENT_TI(r13);	\
 	ld	r4,TI_LOCAL_FLAGS(r3);		\
 	andi.	r0,r4,_TLF_RUNLATCH;		\
 	beql	ppc64_runlatch_on_trampoline;	\
@@ -721,7 +721,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CTRL)
 #ifdef CONFIG_PPC_970_NAP
 #define FINISH_NAP				\
 BEGIN_FTR_SECTION				\
-	CURRENT_THREAD_INFO(r11, r1);		\
+	ld	r11, PACA_CURRENT_TI(r13);	\
 	ld	r9,TI_LOCAL_FLAGS(r11);		\
 	andi.	r10,r9,_TLF_NAPPING;		\
 	bnel	power4_fixup_nap;		\
diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
index ee39ce56b2a2..c91a60cda4fa 100644
--- a/arch/powerpc/include/asm/irq.h
+++ b/arch/powerpc/include/asm/irq.h
@@ -48,23 +48,19 @@ struct pt_regs;
  * Per-cpu stacks for handling critical, debug and machine check
  * level interrupts.
  */
-extern struct thread_info *critirq_ctx[NR_CPUS];
-extern struct thread_info *dbgirq_ctx[NR_CPUS];
-extern struct thread_info *mcheckirq_ctx[NR_CPUS];
-extern void exc_lvl_ctx_init(void);
-#else
-#define exc_lvl_ctx_init()
+extern void *critirq_ctx[NR_CPUS];
+extern void *dbgirq_ctx[NR_CPUS];
+extern void *mcheckirq_ctx[NR_CPUS];
 #endif
 
 /*
  * Per-cpu stacks for handling hard and soft interrupts.
  */
-extern struct thread_info *hardirq_ctx[NR_CPUS];
-extern struct thread_info *softirq_ctx[NR_CPUS];
+extern void *hardirq_ctx[NR_CPUS];
+extern void *softirq_ctx[NR_CPUS];
 
-extern void irq_ctx_init(void);
-extern void call_do_softirq(struct thread_info *tp);
-extern void call_do_irq(struct pt_regs *regs, struct thread_info *tp);
+void call_do_softirq(void *sp);
+void call_do_irq(struct pt_regs *regs, void *sp);
 extern void do_IRQ(struct pt_regs *regs);
 extern void __init init_IRQ(void);
 extern void __do_irq(struct pt_regs *regs);
diff --git a/arch/powerpc/include/asm/livepatch.h b/arch/powerpc/include/asm/livepatch.h
index 47a03b9b528b..5070df19d463 100644
--- a/arch/powerpc/include/asm/livepatch.h
+++ b/arch/powerpc/include/asm/livepatch.h
@@ -21,6 +21,7 @@
 
 #include <linux/module.h>
 #include <linux/ftrace.h>
+#include <linux/sched/task_stack.h>
 
 #ifdef CONFIG_LIVEPATCH
 static inline int klp_check_compiler_support(void)
@@ -43,13 +44,13 @@ static inline unsigned long klp_get_ftrace_location(unsigned long faddr)
 	return ftrace_location_range(faddr, faddr + 16);
 }
 
-static inline void klp_init_thread_info(struct thread_info *ti)
+static inline void klp_init_thread_info(struct task_struct *p)
 {
 	/* + 1 to account for STACK_END_MAGIC */
-	ti->livepatch_sp = (unsigned long *)(ti + 1) + 1;
+	task_thread_info(p)->livepatch_sp = end_of_stack(p) + 1;
 }
 #else
-static void klp_init_thread_info(struct thread_info *ti) { }
+static inline void klp_init_thread_info(struct task_struct *p) { }
 #endif /* CONFIG_LIVEPATCH */
 
 #endif /* _ASM_POWERPC_LIVEPATCH_H */
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index ee58526cb6c2..ba2f0bc680e4 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -40,7 +40,7 @@
 
 #ifndef __ASSEMBLY__
 #include <linux/types.h>
-#include <asm/thread_info.h>
+#include <linux/thread_info.h>
 #include <asm/ptrace.h>
 #include <asm/hw_breakpoint.h>
 
@@ -77,105 +77,15 @@ extern int _chrp_type;
 
 #ifdef __KERNEL__
 
-struct task_struct;
-void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp);
-void release_thread(struct task_struct *);
-
-#ifdef CONFIG_PPC32
-
-#if CONFIG_TASK_SIZE > CONFIG_KERNEL_START
-#error User TASK_SIZE overlaps with KERNEL_START address
-#endif
-#define TASK_SIZE	(CONFIG_TASK_SIZE)
-
-/* This decides where the kernel will search for a free chunk of vm
- * space during mmap's.
- */
-#define TASK_UNMAPPED_BASE	(TASK_SIZE / 8 * 3)
-#endif
-
 #ifdef CONFIG_PPC64
-/*
- * 64-bit user address space can have multiple limits
- * For now supported values are:
- */
-#define TASK_SIZE_64TB  (0x0000400000000000UL)
-#define TASK_SIZE_128TB (0x0000800000000000UL)
-#define TASK_SIZE_512TB (0x0002000000000000UL)
-#define TASK_SIZE_1PB   (0x0004000000000000UL)
-#define TASK_SIZE_2PB   (0x0008000000000000UL)
-/*
- * With 52 bits in the address we can support
- * upto 4PB of range.
- */
-#define TASK_SIZE_4PB   (0x0010000000000000UL)
-
-/*
- * For now 512TB is only supported with book3s and 64K linux page size.
- */
-#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_64K_PAGES)
-/*
- * Max value currently used:
- */
-#define TASK_SIZE_USER64		TASK_SIZE_4PB
-#define DEFAULT_MAP_WINDOW_USER64	TASK_SIZE_128TB
-#define TASK_CONTEXT_SIZE		TASK_SIZE_512TB
-#else
-#define TASK_SIZE_USER64		TASK_SIZE_64TB
-#define DEFAULT_MAP_WINDOW_USER64	TASK_SIZE_64TB
-/*
- * We don't need to allocate extended context ids for 4K page size, because
- * we limit the max effective address on this config to 64TB.
- */
-#define TASK_CONTEXT_SIZE		TASK_SIZE_64TB
-#endif
-
-/*
- * 32-bit user address space is 4GB - 1 page
- * (this 1 page is needed so referencing of 0xFFFFFFFF generates EFAULT
- */
-#define TASK_SIZE_USER32 (0x0000000100000000UL - (1*PAGE_SIZE))
-
-#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
-		TASK_SIZE_USER32 : TASK_SIZE_USER64)
-#define TASK_SIZE	  TASK_SIZE_OF(current)
-/* This decides where the kernel will search for a free chunk of vm
- * space during mmap's.
- */
-#define TASK_UNMAPPED_BASE_USER32 (PAGE_ALIGN(TASK_SIZE_USER32 / 4))
-#define TASK_UNMAPPED_BASE_USER64 (PAGE_ALIGN(DEFAULT_MAP_WINDOW_USER64 / 4))
-
-#define TASK_UNMAPPED_BASE ((is_32bit_task()) ? \
-		TASK_UNMAPPED_BASE_USER32 : TASK_UNMAPPED_BASE_USER64 )
-#endif
-
-/*
- * Initial task size value for user applications. For book3s 64 we start
- * with 128TB and conditionally enable upto 512TB
- */
-#ifdef CONFIG_PPC_BOOK3S_64
-#define DEFAULT_MAP_WINDOW	((is_32bit_task()) ?			\
-				 TASK_SIZE_USER32 : DEFAULT_MAP_WINDOW_USER64)
+#include <asm/task_size_64.h>
 #else
-#define DEFAULT_MAP_WINDOW	TASK_SIZE
+#include <asm/task_size_32.h>
 #endif
 
-#ifdef __powerpc64__
-
-#define STACK_TOP_USER64 DEFAULT_MAP_WINDOW_USER64
-#define STACK_TOP_USER32 TASK_SIZE_USER32
-
-#define STACK_TOP (is_32bit_task() ? \
-		   STACK_TOP_USER32 : STACK_TOP_USER64)
-
-#define STACK_TOP_MAX TASK_SIZE_USER64
-
-#else /* __powerpc64__ */
-
-#define STACK_TOP TASK_SIZE
-#define STACK_TOP_MAX	STACK_TOP
-
-#endif /* __powerpc64__ */
+struct task_struct;
+void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp);
+void release_thread(struct task_struct *);
 
 typedef struct {
 	unsigned long seg;
@@ -357,8 +267,7 @@ struct thread_struct {
 #define ARCH_MIN_TASKALIGN 16
 
 #define INIT_SP		(sizeof(init_stack) + (unsigned long) &init_stack)
-#define INIT_SP_LIMIT \
-	(_ALIGN_UP(sizeof(init_thread_info), 16) + (unsigned long) &init_stack)
+#define INIT_SP_LIMIT	((unsigned long)&init_stack)
 
 #ifdef CONFIG_SPE
 #define SPEFSCR_INIT \
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index 0b8a735b6d85..64271e562fed 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -157,7 +157,7 @@ extern int ptrace_put_reg(struct task_struct *task, int regno,
 			  unsigned long data);
 
 #define current_pt_regs() \
-	((struct pt_regs *)((unsigned long)current_thread_info() + THREAD_SIZE) - 1)
+	((struct pt_regs *)((unsigned long)task_stack_page(current) + THREAD_SIZE) - 1)
 /*
  * We use the least-significant bit of the trap field to indicate
  * whether we have saved the full set of registers, or only a
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 1c98ef1f2d5b..581e61db2dcf 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -1062,7 +1062,7 @@
  *	- SPRG9 debug exception scratch
  *
  * All 32-bit:
- *	- SPRG3 current thread_info pointer
+ *	- SPRG3 current thread_struct physical addr pointer
  *        (virtual on BookE, physical on others)
  *
  * 32-bit classic:
diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h
index 41695745032c..0de717e16dd6 100644
--- a/arch/powerpc/include/asm/smp.h
+++ b/arch/powerpc/include/asm/smp.h
@@ -83,7 +83,22 @@ int is_cpu_dead(unsigned int cpu);
 /* 32-bit */
 extern int smp_hw_index[];
 
-#define raw_smp_processor_id()	(current_thread_info()->cpu)
+/*
+ * This is particularly ugly: it appears we can't actually get the definition
+ * of task_struct here, but we need access to the CPU this task is running on.
+ * Instead of using task_struct we're using _TASK_CPU which is extracted from
+ * asm-offsets.h by kbuild to get the current processor ID.
+ *
+ * This also needs to be safeguarded when building asm-offsets.s because at
+ * that time _TASK_CPU is not defined yet. It could have been guarded by
+ * _TASK_CPU itself, but we want the build to fail if _TASK_CPU is missing
+ * when building something else than asm-offsets.s
+ */
+#ifdef GENERATING_ASM_OFFSETS
+#define raw_smp_processor_id()		(0)
+#else
+#define raw_smp_processor_id()		(*(unsigned int *)((void *)current + _TASK_CPU))
+#endif
 #define hard_smp_processor_id() 	(smp_hw_index[smp_processor_id()])
 
 static inline int get_hard_smp_processor_id(int cpu)
diff --git a/arch/powerpc/include/asm/task_size_32.h b/arch/powerpc/include/asm/task_size_32.h
new file mode 100644
index 000000000000..de7290ee770f
--- /dev/null
+++ b/arch/powerpc/include/asm/task_size_32.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_TASK_SIZE_32_H
+#define _ASM_POWERPC_TASK_SIZE_32_H
+
+#if CONFIG_TASK_SIZE > CONFIG_KERNEL_START
+#error User TASK_SIZE overlaps with KERNEL_START address
+#endif
+
+#define TASK_SIZE (CONFIG_TASK_SIZE)
+
+/*
+ * This decides where the kernel will search for a free chunk of vm space during
+ * mmap's.
+ */
+#define TASK_UNMAPPED_BASE (TASK_SIZE / 8 * 3)
+
+#define DEFAULT_MAP_WINDOW TASK_SIZE
+#define STACK_TOP TASK_SIZE
+#define STACK_TOP_MAX STACK_TOP
+
+#endif /* _ASM_POWERPC_TASK_SIZE_32_H */
diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h
new file mode 100644
index 000000000000..eab4779f6b84
--- /dev/null
+++ b/arch/powerpc/include/asm/task_size_64.h
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_TASK_SIZE_64_H
+#define _ASM_POWERPC_TASK_SIZE_64_H
+
+/*
+ * 64-bit user address space can have multiple limits
+ * For now supported values are:
+ */
+#define TASK_SIZE_64TB  (0x0000400000000000UL)
+#define TASK_SIZE_128TB (0x0000800000000000UL)
+#define TASK_SIZE_512TB (0x0002000000000000UL)
+#define TASK_SIZE_1PB   (0x0004000000000000UL)
+#define TASK_SIZE_2PB   (0x0008000000000000UL)
+
+/*
+ * With 52 bits in the address we can support up to 4PB of range.
+ */
+#define TASK_SIZE_4PB   (0x0010000000000000UL)
+
+/*
+ * For now 512TB is only supported with book3s and 64K linux page size.
+ */
+#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_PPC_64K_PAGES)
+/*
+ * Max value currently used:
+ */
+#define TASK_SIZE_USER64		TASK_SIZE_4PB
+#define DEFAULT_MAP_WINDOW_USER64	TASK_SIZE_128TB
+#define TASK_CONTEXT_SIZE		TASK_SIZE_512TB
+#else
+#define TASK_SIZE_USER64		TASK_SIZE_64TB
+#define DEFAULT_MAP_WINDOW_USER64	TASK_SIZE_64TB
+
+/*
+ * We don't need to allocate extended context ids for 4K page size, because we
+ * limit the max effective address on this config to 64TB.
+ */
+#define TASK_CONTEXT_SIZE TASK_SIZE_64TB
+#endif
+
+/*
+ * 32-bit user address space is 4GB - 1 page
+ * (this 1 page is needed so referencing of 0xFFFFFFFF generates EFAULT
+ */
+#define TASK_SIZE_USER32 (0x0000000100000000UL - (1 * PAGE_SIZE))
+
+#define TASK_SIZE_OF(tsk)						\
+	(test_tsk_thread_flag(tsk, TIF_32BIT) ? TASK_SIZE_USER32 :	\
+						TASK_SIZE_USER64)
+
+#define TASK_SIZE TASK_SIZE_OF(current)
+
+#define TASK_UNMAPPED_BASE_USER32 (PAGE_ALIGN(TASK_SIZE_USER32 / 4))
+#define TASK_UNMAPPED_BASE_USER64 (PAGE_ALIGN(DEFAULT_MAP_WINDOW_USER64 / 4))
+
+/*
+ * This decides where the kernel will search for a free chunk of vm space during
+ * mmap's.
+ */
+#define TASK_UNMAPPED_BASE	\
+	((is_32bit_task()) ? TASK_UNMAPPED_BASE_USER32 : TASK_UNMAPPED_BASE_USER64)
+
+/*
+ * Initial task size value for user applications. For book3s 64 we start
+ * with 128TB and conditionally enable upto 512TB
+ */
+#ifdef CONFIG_PPC_BOOK3S_64
+#define DEFAULT_MAP_WINDOW	\
+	((is_32bit_task()) ? TASK_SIZE_USER32 : DEFAULT_MAP_WINDOW_USER64)
+#else
+#define DEFAULT_MAP_WINDOW	TASK_SIZE
+#endif
+
+#define STACK_TOP_USER64 DEFAULT_MAP_WINDOW_USER64
+#define STACK_TOP_USER32 TASK_SIZE_USER32
+#define STACK_TOP_MAX TASK_SIZE_USER64
+#define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64)
+
+#endif /* _ASM_POWERPC_TASK_SIZE_64_H */
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index 544cac0474cb..8e1d0195ac36 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -17,12 +17,6 @@
 
 #define THREAD_SIZE		(1 << THREAD_SHIFT)
 
-#ifdef CONFIG_PPC64
-#define CURRENT_THREAD_INFO(dest, sp)	stringify_in_c(clrrdi dest, sp, THREAD_SHIFT)
-#else
-#define CURRENT_THREAD_INFO(dest, sp)	stringify_in_c(rlwinm dest, sp, 0, 0, 31-THREAD_SHIFT)
-#endif
-
 #ifndef __ASSEMBLY__
 #include <linux/cache.h>
 #include <asm/processor.h>
@@ -34,8 +28,6 @@
  * low level task data.
  */
 struct thread_info {
-	struct task_struct *task;		/* main task structure */
-	int		cpu;			/* cpu we're on */
 	int		preempt_count;		/* 0 => preemptable,
 						   <0 => BUG */
 	unsigned long	local_flags;		/* private flags for thread */
@@ -58,8 +50,6 @@ struct thread_info {
  */
 #define INIT_THREAD_INFO(tsk)			\
 {						\
-	.task =		&tsk,			\
-	.cpu =		0,			\
 	.preempt_count = INIT_PREEMPT_COUNT,	\
 	.flags =	0,			\
 }
@@ -67,15 +57,6 @@ struct thread_info {
 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
 
 /* how to get the thread information struct from C */
-static inline struct thread_info *current_thread_info(void)
-{
-	unsigned long val;
-
-	asm (CURRENT_THREAD_INFO(%0,1) : "=r" (val));
-
-	return (struct thread_info *)val;
-}
-
 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
 
 #ifdef CONFIG_PPC_BOOK3S_64
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 9ffc72ded73a..7a1b93c5af63 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -13,6 +13,8 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#define GENERATING_ASM_OFFSETS	/* asm/smp.h */
+
 #include <linux/compat.h>
 #include <linux/signal.h>
 #include <linux/sched.h>
@@ -90,10 +92,12 @@ int main(void)
 	DEFINE(SIGSEGV, SIGSEGV);
 	DEFINE(NMI_MASK, NMI_MASK);
 #else
-	OFFSET(THREAD_INFO, task_struct, stack);
-	DEFINE(THREAD_INFO_GAP, _ALIGN_UP(sizeof(struct thread_info), 16));
 	OFFSET(KSP_LIMIT, thread_struct, ksp_limit);
 #endif /* CONFIG_PPC64 */
+	OFFSET(TASK_STACK, task_struct, stack);
+#ifdef CONFIG_SMP
+	OFFSET(TASK_CPU, task_struct, cpu);
+#endif
 
 #ifdef CONFIG_LIVEPATCH
 	OFFSET(TI_livepatch_sp, thread_info, livepatch_sp);
@@ -161,8 +165,6 @@ int main(void)
 	OFFSET(TI_FLAGS, thread_info, flags);
 	OFFSET(TI_LOCAL_FLAGS, thread_info, local_flags);
 	OFFSET(TI_PREEMPT, thread_info, preempt_count);
-	OFFSET(TI_TASK, thread_info, task);
-	OFFSET(TI_CPU, thread_info, cpu);
 
 #ifdef CONFIG_PPC64
 	OFFSET(DCACHEL1BLOCKSIZE, ppc64_caches, l1d.block_size);
@@ -177,6 +179,8 @@ int main(void)
 	OFFSET(PACAPROCSTART, paca_struct, cpu_start);
 	OFFSET(PACAKSAVE, paca_struct, kstack);
 	OFFSET(PACACURRENT, paca_struct, __current);
+	DEFINE(PACA_CURRENT_TI, offsetof(struct paca_struct, __current) +
+				offsetof(struct task_struct, thread_info));
 	OFFSET(PACASAVEDMSR, paca_struct, saved_msr);
 	OFFSET(PACAR1, paca_struct, saved_r1);
 	OFFSET(PACATOC, paca_struct, kernel_toc);
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 0768dfd8a64e..a5e2d5585dcb 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -97,14 +97,11 @@ crit_transfer_to_handler:
 	mfspr	r0,SPRN_SRR1
 	stw	r0,_SRR1(r11)
 
-	/* set the stack limit to the current stack
-	 * and set the limit to protect the thread_info
-	 * struct
-	 */
+	/* set the stack limit to the current stack */
 	mfspr	r8,SPRN_SPRG_THREAD
 	lwz	r0,KSP_LIMIT(r8)
 	stw	r0,SAVED_KSP_LIMIT(r11)
-	rlwimi	r0,r1,0,0,(31-THREAD_SHIFT)
+	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
 	stw	r0,KSP_LIMIT(r8)
 	/* fall through */
 #endif
@@ -121,14 +118,11 @@ crit_transfer_to_handler:
 	mfspr	r0,SPRN_SRR1
 	stw	r0,crit_srr1@l(0)
 
-	/* set the stack limit to the current stack
-	 * and set the limit to protect the thread_info
-	 * struct
-	 */
+	/* set the stack limit to the current stack */
 	mfspr	r8,SPRN_SPRG_THREAD
 	lwz	r0,KSP_LIMIT(r8)
 	stw	r0,saved_ksp_limit@l(0)
-	rlwimi	r0,r1,0,0,(31-THREAD_SHIFT)
+	rlwinm	r0,r1,0,0,(31 - THREAD_SHIFT)
 	stw	r0,KSP_LIMIT(r8)
 	/* fall through */
 #endif
@@ -157,7 +151,6 @@ transfer_to_handler:
 	stw	r2,_XER(r11)
 	mfspr	r12,SPRN_SPRG_THREAD
 	addi	r2,r12,-THREAD
-	tovirt(r2,r2)			/* set r2 to current */
 	beq	2f			/* if from user, fix up THREAD.regs */
 	addi	r11,r1,STACK_FRAME_OVERHEAD
 	stw	r11,PT_REGS(r12)
@@ -166,6 +159,9 @@ transfer_to_handler:
 	   internal debug mode bit to do this. */
 	lwz	r12,THREAD_DBCR0(r12)
 	andis.	r12,r12,DBCR0_IDM@h
+#endif
+	ACCOUNT_CPU_USER_ENTRY(r2, r11, r12)
+#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
 	beq+	3f
 	/* From user and task is ptraced - load up global dbcr0 */
 	li	r12,-1			/* clear all pending debug events */
@@ -174,8 +170,7 @@ transfer_to_handler:
 	tophys(r11,r11)
 	addi	r11,r11,global_dbcr0@l
 #ifdef CONFIG_SMP
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r9,TI_CPU(r9)
+	lwz	r9,TASK_CPU(r2)
 	slwi	r9,r9,3
 	add	r11,r11,r9
 #endif
@@ -185,11 +180,6 @@ transfer_to_handler:
 	addi	r12,r12,-1
 	stw	r12,4(r11)
 #endif
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-	CURRENT_THREAD_INFO(r9, r1)
-	tophys(r9, r9)
-	ACCOUNT_CPU_USER_ENTRY(r9, r11, r12)
-#endif
 
 	b	3f
 
@@ -201,9 +191,7 @@ transfer_to_handler:
 	ble-	stack_ovf		/* then the kernel stack overflowed */
 5:
 #if defined(CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
-	CURRENT_THREAD_INFO(r9, r1)
-	tophys(r9,r9)			/* check local flags */
-	lwz	r12,TI_LOCAL_FLAGS(r9)
+	lwz	r12,TI_LOCAL_FLAGS(r2)
 	mtcrf	0x01,r12
 	bt-	31-TLF_NAPPING,4f
 	bt-	31-TLF_SLEEPING,7f
@@ -212,6 +200,7 @@ transfer_to_handler:
 transfer_to_handler_cont:
 3:
 	mflr	r9
+	tovirt(r2, r2)			/* set r2 to current */
 	lwz	r11,0(r9)		/* virtual address of handler */
 	lwz	r9,4(r9)		/* where to go when done */
 #if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS)
@@ -275,11 +264,11 @@ reenable_mmu:				/* re-enable mmu so we can */
 
 #if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
 4:	rlwinm	r12,r12,0,~_TLF_NAPPING
-	stw	r12,TI_LOCAL_FLAGS(r9)
+	stw	r12,TI_LOCAL_FLAGS(r2)
 	b	power_save_ppc32_restore
 
 7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
-	stw	r12,TI_LOCAL_FLAGS(r9)
+	stw	r12,TI_LOCAL_FLAGS(r2)
 	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
 	rlwinm	r9,r9,0,~MSR_EE
 	lwz	r12,_LINK(r11)		/* and return to address in LR */
@@ -351,8 +340,7 @@ _GLOBAL(DoSyscall)
 	mtmsr	r11
 1:
 #endif /* CONFIG_TRACE_IRQFLAGS */
-	CURRENT_THREAD_INFO(r10, r1)
-	lwz	r11,TI_FLAGS(r10)
+	lwz	r11,TI_FLAGS(r2)
 	andi.	r11,r11,_TIF_SYSCALL_DOTRACE
 	bne-	syscall_dotrace
 syscall_dotrace_cont:
@@ -385,13 +373,12 @@ ret_from_syscall:
 	lwz	r3,GPR3(r1)
 #endif
 	mr	r6,r3
-	CURRENT_THREAD_INFO(r12, r1)
 	/* disable interrupts so current_thread_info()->flags can't change */
 	LOAD_MSR_KERNEL(r10,MSR_KERNEL)	/* doesn't include MSR_EE */
 	/* Note: We don't bother telling lockdep about it */
 	SYNC
 	MTMSRD(r10)
-	lwz	r9,TI_FLAGS(r12)
+	lwz	r9,TI_FLAGS(r2)
 	li	r8,-MAX_ERRNO
 	andi.	r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
 	bne-	syscall_exit_work
@@ -438,8 +425,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 	andi.	r4,r8,MSR_PR
 	beq	3f
-	CURRENT_THREAD_INFO(r4, r1)
-	ACCOUNT_CPU_USER_EXIT(r4, r5, r7)
+	ACCOUNT_CPU_USER_EXIT(r2, r5, r7)
 3:
 #endif
 	lwz	r4,_LINK(r1)
@@ -532,7 +518,7 @@ syscall_exit_work:
 	/* Clear per-syscall TIF flags if any are set.  */
 
 	li	r11,_TIF_PERSYSCALL_MASK
-	addi	r12,r12,TI_FLAGS
+	addi	r12,r2,TI_FLAGS
 3:	lwarx	r8,0,r12
 	andc	r8,r8,r11
 #ifdef CONFIG_IBM405_ERR77
@@ -540,7 +526,6 @@ syscall_exit_work:
 #endif
 	stwcx.	r8,0,r12
 	bne-	3b
-	subi	r12,r12,TI_FLAGS
 	
 4:	/* Anything which requires enabling interrupts? */
 	andi.	r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP)
@@ -819,8 +804,7 @@ ret_from_except:
 
 user_exc_return:		/* r10 contains MSR_KERNEL here */
 	/* Check current_thread_info()->flags */
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r9,TI_FLAGS(r9)
+	lwz	r9,TI_FLAGS(r2)
 	andi.	r0,r9,_TIF_USER_WORK_MASK
 	bne	do_work
 
@@ -832,18 +816,14 @@ restore_user:
 	andis.	r10,r0,DBCR0_IDM@h
 	bnel-	load_dbcr0
 #endif
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-	CURRENT_THREAD_INFO(r9, r1)
-	ACCOUNT_CPU_USER_EXIT(r9, r10, r11)
-#endif
+	ACCOUNT_CPU_USER_EXIT(r2, r10, r11)
 
 	b	restore
 
 /* N.B. the only way to get here is from the beq following ret_from_except. */
 resume_kernel:
 	/* check current_thread_info, _TIF_EMULATE_STACK_STORE */
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r8,TI_FLAGS(r9)
+	lwz	r8,TI_FLAGS(r2)
 	andis.	r0,r8,_TIF_EMULATE_STACK_STORE@h
 	beq+	1f
 
@@ -869,7 +849,7 @@ resume_kernel:
 
 	/* Clear _TIF_EMULATE_STACK_STORE flag */
 	lis	r11,_TIF_EMULATE_STACK_STORE@h
-	addi	r5,r9,TI_FLAGS
+	addi	r5,r2,TI_FLAGS
 0:	lwarx	r8,0,r5
 	andc	r8,r8,r11
 #ifdef CONFIG_IBM405_ERR77
@@ -881,7 +861,7 @@ resume_kernel:
 
 #ifdef CONFIG_PREEMPT
 	/* check current_thread_info->preempt_count */
-	lwz	r0,TI_PREEMPT(r9)
+	lwz	r0,TI_PREEMPT(r2)
 	cmpwi	0,r0,0		/* if non-zero, just restore regs and return */
 	bne	restore
 	andi.	r8,r8,_TIF_NEED_RESCHED
@@ -897,8 +877,7 @@ resume_kernel:
 	bl	trace_hardirqs_off
 #endif
 1:	bl	preempt_schedule_irq
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r3,TI_FLAGS(r9)
+	lwz	r3,TI_FLAGS(r2)
 	andi.	r0,r3,_TIF_NEED_RESCHED
 	bne-	1b
 #ifdef CONFIG_TRACE_IRQFLAGS
@@ -1166,10 +1145,6 @@ ret_from_debug_exc:
 	mfspr	r9,SPRN_SPRG_THREAD
 	lwz	r10,SAVED_KSP_LIMIT(r1)
 	stw	r10,KSP_LIMIT(r9)
-	lwz	r9,THREAD_INFO-THREAD(r9)
-	CURRENT_THREAD_INFO(r10, r1)
-	lwz	r10,TI_PREEMPT(r10)
-	stw	r10,TI_PREEMPT(r9)
 	RESTORE_xSRR(SRR0,SRR1);
 	RESTORE_xSRR(CSRR0,CSRR1);
 	RESTORE_MMU_REGS;
@@ -1201,8 +1176,7 @@ load_dbcr0:
 	lis	r11,global_dbcr0@ha
 	addi	r11,r11,global_dbcr0@l
 #ifdef CONFIG_SMP
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r9,TI_CPU(r9)
+	lwz	r9,TASK_CPU(r2)
 	slwi	r9,r9,3
 	add	r11,r11,r9
 #endif
@@ -1242,8 +1216,7 @@ recheck:
 	LOAD_MSR_KERNEL(r10,MSR_KERNEL)
 	SYNC
 	MTMSRD(r10)		/* disable interrupts */
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r9,TI_FLAGS(r9)
+	lwz	r9,TI_FLAGS(r2)
 	andi.	r0,r9,_TIF_NEED_RESCHED
 	bne-	do_resched
 	andi.	r0,r9,_TIF_USER_WORK_MASK
@@ -1292,10 +1265,13 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_601)
 	lwz	r3,_TRAP(r1)
 	andi.	r0,r3,1
-	beq	4f
+	beq	5f
 	SAVE_NVGPRS(r1)
 	rlwinm	r3,r3,0,0,30
 	stw	r3,_TRAP(r1)
+5:	mfspr	r2,SPRN_SPRG_THREAD
+	addi	r2,r2,-THREAD
+	tovirt(r2,r2)			/* set back r2 to current */
 4:	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	unrecoverable_exception
 	/* shouldn't return */
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index a2c168b395d2..56e95ed9b0ab 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -166,7 +166,7 @@ system_call:			/* label this so stack traces look sane */
 	li	r10,IRQS_ENABLED
 	std	r10,SOFTE(r1)
 
-	CURRENT_THREAD_INFO(r11, r1)
+	ld	r11, PACA_CURRENT_TI(r13)
 	ld	r10,TI_FLAGS(r11)
 	andi.	r11,r10,_TIF_SYSCALL_DOTRACE
 	bne	.Lsyscall_dotrace		/* does not return */
@@ -213,7 +213,7 @@ system_call:			/* label this so stack traces look sane */
 	ld	r3,RESULT(r1)
 #endif
 
-	CURRENT_THREAD_INFO(r12, r1)
+	ld	r12, PACA_CURRENT_TI(r13)
 
 	ld	r8,_MSR(r1)
 #ifdef CONFIG_PPC_BOOK3S
@@ -348,7 +348,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 
 	/* Repopulate r9 and r10 for the syscall path */
 	addi	r9,r1,STACK_FRAME_OVERHEAD
-	CURRENT_THREAD_INFO(r10, r1)
+	ld	r10, PACA_CURRENT_TI(r13)
 	ld	r10,TI_FLAGS(r10)
 
 	cmpldi	r0,NR_syscalls
@@ -695,7 +695,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 2:
 #endif /* CONFIG_PPC_BOOK3S_64 */
 
-	CURRENT_THREAD_INFO(r7, r8)  /* base of new stack */
+	clrrdi	r7, r8, THREAD_SHIFT	/* base of new stack */
 	/* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE
 	   because we don't need to leave the 288-byte ABI gap at the
 	   top of the kernel stack. */
@@ -746,7 +746,7 @@ _GLOBAL(ret_from_except_lite)
 	mtmsrd	r10,1		  /* Update machine state */
 #endif /* CONFIG_PPC_BOOK3E */
 
-	CURRENT_THREAD_INFO(r9, r1)
+	ld	r9, PACA_CURRENT_TI(r13)
 	ld	r3,_MSR(r1)
 #ifdef CONFIG_PPC_BOOK3E
 	ld	r10,PACACURRENT(r13)
@@ -860,7 +860,7 @@ resume_kernel:
 1:	bl	preempt_schedule_irq
 
 	/* Re-test flags and eventually loop */
-	CURRENT_THREAD_INFO(r9, r1)
+	ld	r9, PACA_CURRENT_TI(r13)
 	ld	r4,TI_FLAGS(r9)
 	andi.	r0,r4,_TIF_NEED_RESCHED
 	bne	1b
diff --git a/arch/powerpc/kernel/epapr_hcalls.S b/arch/powerpc/kernel/epapr_hcalls.S
index 52ca2471ee1a..d252f4663a23 100644
--- a/arch/powerpc/kernel/epapr_hcalls.S
+++ b/arch/powerpc/kernel/epapr_hcalls.S
@@ -21,10 +21,9 @@
 #ifndef CONFIG_PPC64
 /* epapr_ev_idle() was derived from e500_idle() */
 _GLOBAL(epapr_ev_idle)
-	CURRENT_THREAD_INFO(r3, r1)
-	PPC_LL	r4, TI_LOCAL_FLAGS(r3)	/* set napping bit */
+	PPC_LL	r4, TI_LOCAL_FLAGS(r2)	/* set napping bit */
 	ori	r4, r4,_TLF_NAPPING	/* so when we take an exception */
-	PPC_STL	r4, TI_LOCAL_FLAGS(r3)	/* it will return to our caller */
+	PPC_STL	r4, TI_LOCAL_FLAGS(r2)	/* it will return to our caller */
 
 	wrteei	1
 
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index afb638778f44..92d5ded2b290 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -77,17 +77,6 @@ special_reg_save:
 	andi.	r3,r3,MSR_PR
 	bnelr
 
-	/* Copy info into temporary exception thread info */
-	ld	r11,PACAKSAVE(r13)
-	CURRENT_THREAD_INFO(r11, r11)
-	CURRENT_THREAD_INFO(r12, r1)
-	ld	r10,TI_FLAGS(r11)
-	std	r10,TI_FLAGS(r12)
-	ld	r10,TI_PREEMPT(r11)
-	std	r10,TI_PREEMPT(r12)
-	ld	r10,TI_TASK(r11)
-	std	r10,TI_TASK(r12)
-
 	/*
 	 * Advance to the next TLB exception frame for handler
 	 * types that don't do it automatically.
@@ -504,7 +493,7 @@ exc_##n##_bad_stack:							    \
  * interrupts happen before the wait instruction.
  */
 #define CHECK_NAPPING()							\
-	CURRENT_THREAD_INFO(r11, r1);					\
+	ld	r11, PACA_CURRENT_TI(r13);				\
 	ld	r10,TI_LOCAL_FLAGS(r11);				\
 	andi.	r9,r10,_TLF_NAPPING;					\
 	beq+	1f;							\
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 9e253ce27e08..83be18d478b8 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1629,7 +1629,7 @@ do_hash_page:
 	ori	r0,r0,DSISR_BAD_FAULT_64S@l
 	and.	r0,r4,r0		/* weird error? */
 	bne-	handle_page_fault	/* if not, try to insert a HPTE */
-	CURRENT_THREAD_INFO(r11, r1)
+	ld	r11, PACA_CURRENT_TI(r13)
 	lwz	r0,TI_PREEMPT(r11)	/* If we're in an "NMI" */
 	andis.	r0,r0,NMI_MASK@h	/* (i.e. an irq when soft-disabled) */
 	bne	77f			/* then don't call hash_page now */
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 05b08db3901d..146385b1c2da 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -261,7 +261,7 @@ __secondary_hold_acknowledge:
 	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
 	beq	1f;		\
 	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,THREAD_INFO-THREAD(r11);	\
+	lwz	r11,TASK_STACK-THREAD(r11);	\
 	addi	r11,r11,THREAD_SIZE;	\
 	tophys(r11,r11);	\
 1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
@@ -845,12 +845,12 @@ __secondary_start:
 	bl	init_idle_6xx
 #endif /* CONFIG_PPC_BOOK3S_32 */
 
-	/* get current_thread_info and current */
-	lis	r1,secondary_ti@ha
-	tophys(r1,r1)
-	lwz	r1,secondary_ti@l(r1)
-	tophys(r2,r1)
-	lwz	r2,TI_TASK(r2)
+	/* get current's stack and current */
+	lis	r2,secondary_current@ha
+	tophys(r2,r2)
+	lwz	r2,secondary_current@l(r2)
+	tophys(r1,r2)
+	lwz	r1,TASK_STACK(r1)
 
 	/* stack */
 	addi	r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index b19d78410511..3088c9f29f5e 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -115,7 +115,7 @@ _ENTRY(saved_ksp_limit)
 	andi.	r11,r11,MSR_PR;						     \
 	beq	1f;							     \
 	mfspr	r1,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r1,THREAD_INFO-THREAD(r1); /* this thread's kernel stack   */\
+	lwz	r1,TASK_STACK-THREAD(r1); /* this thread's kernel stack   */\
 	addi	r1,r1,THREAD_SIZE;					     \
 1:	subi	r1,r1,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
 	tophys(r11,r1);							     \
@@ -158,7 +158,7 @@ _ENTRY(saved_ksp_limit)
 	beq	1f;							     \
 	/* COMING FROM USER MODE */					     \
 	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
+	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
 1:	addi	r11,r11,THREAD_SIZE-INT_FRAME_SIZE; /* Alloc an excpt frm  */\
 	tophys(r11,r11);						     \
 	stw	r10,_CCR(r11);          /* save various registers	   */\
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S
index bf23c19c92d6..37117ab11584 100644
--- a/arch/powerpc/kernel/head_44x.S
+++ b/arch/powerpc/kernel/head_44x.S
@@ -1019,10 +1019,10 @@ _GLOBAL(start_secondary_47x)
 
 	/* Now we can get our task struct and real stack pointer */
 
-	/* Get current_thread_info and current */
-	lis	r1,secondary_ti@ha
-	lwz	r1,secondary_ti@l(r1)
-	lwz	r2,TI_TASK(r1)
+	/* Get current's stack and current */
+	lis	r2,secondary_current@ha
+	lwz	r2,secondary_current@l(r2)
+	lwz	r1,TASK_STACK(r2)
 
 	/* Current stack pointer */
 	addi	r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 4898e9491a1c..c6a9bf7b34bf 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -805,6 +805,7 @@ __secondary_start:
 	LOAD_REG_ADDR(r3, current_set)
 	sldi	r28,r24,3		/* get current_set[cpu#]	 */
 	ldx	r14,r3,r28
+	ld	r14,TASK_STACK(r14)
 	addi	r14,r14,THREAD_SIZE-STACK_FRAME_OVERHEAD
 	std	r14,PACAKSAVE(r13)
 
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 20cc816b3508..ca9207013579 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -142,7 +142,7 @@ instruction_counter:
 	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
 	beq	1f;		\
 	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,THREAD_INFO-THREAD(r11);	\
+	lwz	r11,TASK_STACK-THREAD(r11);	\
 	addi	r11,r11,THREAD_SIZE;	\
 	tophys(r11,r11);	\
 1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index 306e26c073a0..1b22a8dea399 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -55,7 +55,7 @@ END_BTB_FLUSH_SECTION
 	beq	1f;							     \
 	BOOKE_CLEAR_BTB(r11)						\
 	/* if from user, start at top of this thread's kernel stack */       \
-	lwz	r11, THREAD_INFO-THREAD(r10);				     \
+	lwz	r11, TASK_STACK - THREAD(r10);				     \
 	ALLOC_STACK_FRAME(r11, THREAD_SIZE);				     \
 1 :	subi	r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */     \
 	stw	r13, _CCR(r11);		/* save various registers */	     \
@@ -142,7 +142,7 @@ END_BTB_FLUSH_SECTION
 	BOOKE_CLEAR_BTB(r10)						\
 	andi.	r11,r11,MSR_PR;						     \
 	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
+	lwz	r11, TASK_STACK - THREAD(r11); /* this thread's kernel stack */\
 	addi	r11,r11,EXC_LVL_FRAME_OVERHEAD;	/* allocate stack frame    */\
 	beq	1f;							     \
 	/* COMING FROM USER MODE */					     \
@@ -155,13 +155,7 @@ END_BTB_FLUSH_SECTION
 	stw	r10,GPR11(r11);						     \
 	b	2f;							     \
 	/* COMING FROM PRIV MODE */					     \
-1:	lwz	r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r11);		     \
-	lwz	r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r11);		     \
-	stw	r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r8);			     \
-	stw	r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r8);		     \
-	lwz	r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r11);			     \
-	stw	r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r8);			     \
-	mr	r11,r8;							     \
+1:	mr	r11, r8;							     \
 2:	mfspr	r8,SPRN_SPRG_RSCRATCH_##exc_level;			     \
 	stw	r12,GPR12(r11);		/* save various registers	   */\
 	mflr	r10;							     \
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 2386ce2a9c6e..1881127682e9 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -243,8 +243,9 @@ set_ivor:
 	li	r0,0
 	stwu	r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
 
-	CURRENT_THREAD_INFO(r22, r1)
-	stw	r24, TI_CPU(r22)
+#ifdef CONFIG_SMP
+	stw	r24, TASK_CPU(r2)
+#endif
 
 	bl	early_init
 
@@ -717,8 +718,7 @@ finish_tlb_load:
 
 	/* Get the next_tlbcam_idx percpu var */
 #ifdef CONFIG_SMP
-	lwz	r12, THREAD_INFO-THREAD(r12)
-	lwz	r15, TI_CPU(r12)
+	lwz	r15, TASK_CPU-THREAD(r12)
 	lis     r14, __per_cpu_offset@h
 	ori     r14, r14, __per_cpu_offset@l
 	rlwinm  r15, r15, 2, 0, 29
@@ -1089,10 +1089,10 @@ __secondary_start:
 	mr	r4,r24		/* Why? */
 	bl	call_setup_cpu
 
-	/* get current_thread_info and current */
-	lis	r1,secondary_ti@ha
-	lwz	r1,secondary_ti@l(r1)
-	lwz	r2,TI_TASK(r1)
+	/* get current's stack and current */
+	lis	r2,secondary_current@ha
+	lwz	r2,secondary_current@l(r2)
+	lwz	r1,TASK_STACK(r2)
 
 	/* stack */
 	addi	r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
diff --git a/arch/powerpc/kernel/idle_6xx.S b/arch/powerpc/kernel/idle_6xx.S
index ff026c9d3cab..5afd2e236990 100644
--- a/arch/powerpc/kernel/idle_6xx.S
+++ b/arch/powerpc/kernel/idle_6xx.S
@@ -136,10 +136,9 @@ BEGIN_FTR_SECTION
 	DSSALL
 	sync
 END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r8,TI_LOCAL_FLAGS(r9)	/* set napping bit */
+	lwz	r8,TI_LOCAL_FLAGS(r2)	/* set napping bit */
 	ori	r8,r8,_TLF_NAPPING	/* so when we take an exception */
-	stw	r8,TI_LOCAL_FLAGS(r9)	/* it will return to our caller */
+	stw	r8,TI_LOCAL_FLAGS(r2)	/* it will return to our caller */
 	mfmsr	r7
 	ori	r7,r7,MSR_EE
 	oris	r7,r7,MSR_POW@h
@@ -159,8 +158,7 @@ _GLOBAL(power_save_ppc32_restore)
 	stw	r9,_NIP(r11)		/* make it do a blr */
 
 #ifdef CONFIG_SMP
-	CURRENT_THREAD_INFO(r12, r11)
-	lwz	r11,TI_CPU(r12)		/* get cpu number * 4 */
+	lwz	r11,TASK_CPU(r2)		/* get cpu number * 4 */
 	slwi	r11,r11,2
 #else
 	li	r11,0
diff --git a/arch/powerpc/kernel/idle_book3e.S b/arch/powerpc/kernel/idle_book3e.S
index 4e0d94d02030..31e732c378ad 100644
--- a/arch/powerpc/kernel/idle_book3e.S
+++ b/arch/powerpc/kernel/idle_book3e.S
@@ -63,7 +63,7 @@ _GLOBAL(\name)
 1:	/* Let's set the _TLF_NAPPING flag so interrupts make us return
 	 * to the right spot
 	*/
-	CURRENT_THREAD_INFO(r11, r1)
+	ld	r11, PACACURRENT(r13)
 	ld	r10,TI_LOCAL_FLAGS(r11)
 	ori	r10,r10,_TLF_NAPPING
 	std	r10,TI_LOCAL_FLAGS(r11)
diff --git a/arch/powerpc/kernel/idle_e500.S b/arch/powerpc/kernel/idle_e500.S
index 583e55ac7d26..69dfcd2ca011 100644
--- a/arch/powerpc/kernel/idle_e500.S
+++ b/arch/powerpc/kernel/idle_e500.S
@@ -22,10 +22,9 @@
 	.text
 
 _GLOBAL(e500_idle)
-	CURRENT_THREAD_INFO(r3, r1)
-	lwz	r4,TI_LOCAL_FLAGS(r3)	/* set napping bit */
+	lwz	r4,TI_LOCAL_FLAGS(r2)	/* set napping bit */
 	ori	r4,r4,_TLF_NAPPING	/* so when we take an exception */
-	stw	r4,TI_LOCAL_FLAGS(r3)	/* it will return to our caller */
+	stw	r4,TI_LOCAL_FLAGS(r2)	/* it will return to our caller */
 
 #ifdef CONFIG_PPC_E500MC
 	wrteei	1
@@ -88,8 +87,7 @@ _GLOBAL(power_save_ppc32_restore)
 	stw	r9,_NIP(r11)		/* make it do a blr */
 
 #ifdef CONFIG_SMP
-	CURRENT_THREAD_INFO(r12, r1)
-	lwz	r11,TI_CPU(r12)		/* get cpu number * 4 */
+	lwz	r11,TASK_CPU(r2)		/* get cpu number * 4 */
 	slwi	r11,r11,2
 #else
 	li	r11,0
diff --git a/arch/powerpc/kernel/idle_power4.S b/arch/powerpc/kernel/idle_power4.S
index a09b3c7ca176..b4c849f9f0e2 100644
--- a/arch/powerpc/kernel/idle_power4.S
+++ b/arch/powerpc/kernel/idle_power4.S
@@ -68,7 +68,7 @@ BEGIN_FTR_SECTION
 	DSSALL
 	sync
 END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
-	CURRENT_THREAD_INFO(r9, r1)
+	ld	r9, PACA_CURRENT_TI(r13)
 	ld	r8,TI_LOCAL_FLAGS(r9)	/* set napping bit */
 	ori	r8,r8,_TLF_NAPPING	/* so when we take an exception */
 	std	r8,TI_LOCAL_FLAGS(r9)	/* it will return to our caller */
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index bb299613a462..8a936723c791 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -618,9 +618,8 @@ static inline void check_stack_overflow(void)
 	sp = current_stack_pointer() & (THREAD_SIZE-1);
 
 	/* check for stack overflow: is there less than 2KB free? */
-	if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
-		pr_err("do_IRQ: stack overflow: %ld\n",
-			sp - sizeof(struct thread_info));
+	if (unlikely(sp < 2048)) {
+		pr_err("do_IRQ: stack overflow: %ld\n", sp);
 		dump_stack();
 	}
 #endif
@@ -660,36 +659,21 @@ void __do_irq(struct pt_regs *regs)
 void do_IRQ(struct pt_regs *regs)
 {
 	struct pt_regs *old_regs = set_irq_regs(regs);
-	struct thread_info *curtp, *irqtp, *sirqtp;
+	void *cursp, *irqsp, *sirqsp;
 
 	/* Switch to the irq stack to handle this */
-	curtp = current_thread_info();
-	irqtp = hardirq_ctx[raw_smp_processor_id()];
-	sirqtp = softirq_ctx[raw_smp_processor_id()];
+	cursp = (void *)(current_stack_pointer() & ~(THREAD_SIZE - 1));
+	irqsp = hardirq_ctx[raw_smp_processor_id()];
+	sirqsp = softirq_ctx[raw_smp_processor_id()];
 
 	/* Already there ? */
-	if (unlikely(curtp == irqtp || curtp == sirqtp)) {
+	if (unlikely(cursp == irqsp || cursp == sirqsp)) {
 		__do_irq(regs);
 		set_irq_regs(old_regs);
 		return;
 	}
-
-	/* Prepare the thread_info in the irq stack */
-	irqtp->task = curtp->task;
-	irqtp->flags = 0;
-
-	/* Copy the preempt_count so that the [soft]irq checks work. */
-	irqtp->preempt_count = curtp->preempt_count;
-
 	/* Switch stack and call */
-	call_do_irq(regs, irqtp);
-
-	/* Restore stack limit */
-	irqtp->task = NULL;
-
-	/* Copy back updates to the thread_info */
-	if (irqtp->flags)
-		set_bits(irqtp->flags, &curtp->flags);
+	call_do_irq(regs, irqsp);
 
 	set_irq_regs(old_regs);
 }
@@ -698,90 +682,20 @@ void __init init_IRQ(void)
 {
 	if (ppc_md.init_IRQ)
 		ppc_md.init_IRQ();
-
-	exc_lvl_ctx_init();
-
-	irq_ctx_init();
 }
 
 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
-struct thread_info   *critirq_ctx[NR_CPUS] __read_mostly;
-struct thread_info    *dbgirq_ctx[NR_CPUS] __read_mostly;
-struct thread_info *mcheckirq_ctx[NR_CPUS] __read_mostly;
-
-void exc_lvl_ctx_init(void)
-{
-	struct thread_info *tp;
-	int i, cpu_nr;
-
-	for_each_possible_cpu(i) {
-#ifdef CONFIG_PPC64
-		cpu_nr = i;
-#else
-#ifdef CONFIG_SMP
-		cpu_nr = get_hard_smp_processor_id(i);
-#else
-		cpu_nr = 0;
-#endif
+void   *critirq_ctx[NR_CPUS] __read_mostly;
+void    *dbgirq_ctx[NR_CPUS] __read_mostly;
+void *mcheckirq_ctx[NR_CPUS] __read_mostly;
 #endif
 
-		memset((void *)critirq_ctx[cpu_nr], 0, THREAD_SIZE);
-		tp = critirq_ctx[cpu_nr];
-		tp->cpu = cpu_nr;
-		tp->preempt_count = 0;
-
-#ifdef CONFIG_BOOKE
-		memset((void *)dbgirq_ctx[cpu_nr], 0, THREAD_SIZE);
-		tp = dbgirq_ctx[cpu_nr];
-		tp->cpu = cpu_nr;
-		tp->preempt_count = 0;
-
-		memset((void *)mcheckirq_ctx[cpu_nr], 0, THREAD_SIZE);
-		tp = mcheckirq_ctx[cpu_nr];
-		tp->cpu = cpu_nr;
-		tp->preempt_count = HARDIRQ_OFFSET;
-#endif
-	}
-}
-#endif
-
-struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
-struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
-
-void irq_ctx_init(void)
-{
-	struct thread_info *tp;
-	int i;
-
-	for_each_possible_cpu(i) {
-		memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
-		tp = softirq_ctx[i];
-		tp->cpu = i;
-		klp_init_thread_info(tp);
-
-		memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
-		tp = hardirq_ctx[i];
-		tp->cpu = i;
-		klp_init_thread_info(tp);
-	}
-}
+void *softirq_ctx[NR_CPUS] __read_mostly;
+void *hardirq_ctx[NR_CPUS] __read_mostly;
 
 void do_softirq_own_stack(void)
 {
-	struct thread_info *curtp, *irqtp;
-
-	curtp = current_thread_info();
-	irqtp = softirq_ctx[smp_processor_id()];
-	irqtp->task = curtp->task;
-	irqtp->flags = 0;
-	call_do_softirq(irqtp);
-	irqtp->task = NULL;
-
-	/* Set any flag that may have been set on the
-	 * alternate stack
-	 */
-	if (irqtp->flags)
-		set_bits(irqtp->flags, &curtp->flags);
+	call_do_softirq(softirq_ctx[smp_processor_id()]);
 }
 
 irq_hw_number_t virq_to_hw(unsigned int virq)
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index e1865565f0ae..7dd55eb1259d 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -151,41 +151,13 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs)
 	return 1;
 }
 
-static DEFINE_PER_CPU(struct thread_info, kgdb_thread_info);
 static int kgdb_singlestep(struct pt_regs *regs)
 {
-	struct thread_info *thread_info, *exception_thread_info;
-	struct thread_info *backup_current_thread_info =
-		this_cpu_ptr(&kgdb_thread_info);
-
 	if (user_mode(regs))
 		return 0;
 
-	/*
-	 * On Book E and perhaps other processors, singlestep is handled on
-	 * the critical exception stack.  This causes current_thread_info()
-	 * to fail, since it it locates the thread_info by masking off
-	 * the low bits of the current stack pointer.  We work around
-	 * this issue by copying the thread_info from the kernel stack
-	 * before calling kgdb_handle_exception, and copying it back
-	 * afterwards.  On most processors the copy is avoided since
-	 * exception_thread_info == thread_info.
-	 */
-	thread_info = (struct thread_info *)(regs->gpr[1] & ~(THREAD_SIZE-1));
-	exception_thread_info = current_thread_info();
-
-	if (thread_info != exception_thread_info) {
-		/* Save the original current_thread_info. */
-		memcpy(backup_current_thread_info, exception_thread_info, sizeof *thread_info);
-		memcpy(exception_thread_info, thread_info, sizeof *thread_info);
-	}
-
 	kgdb_handle_exception(0, SIGTRAP, 0, regs);
 
-	if (thread_info != exception_thread_info)
-		/* Restore current_thread_info lastly. */
-		memcpy(exception_thread_info, backup_current_thread_info, sizeof *thread_info);
-
 	return 1;
 }
 
diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c
index a0f6f45005bd..75692c327ba0 100644
--- a/arch/powerpc/kernel/machine_kexec_64.c
+++ b/arch/powerpc/kernel/machine_kexec_64.c
@@ -317,10 +317,8 @@ void default_machine_kexec(struct kimage *image)
 	 * We setup preempt_count to avoid using VMX in memcpy.
 	 * XXX: the task struct will likely be invalid once we do the copy!
 	 */
-	kexec_stack.thread_info.task = current_thread_info()->task;
-	kexec_stack.thread_info.flags = 0;
-	kexec_stack.thread_info.preempt_count = HARDIRQ_OFFSET;
-	kexec_stack.thread_info.cpu = current_thread_info()->cpu;
+	current_thread_info()->flags = 0;
+	current_thread_info()->preempt_count = HARDIRQ_OFFSET;
 
 	/* We need a static PACA, too; copy this CPU's PACA over and switch to
 	 * it. Also poison per_cpu_offset and NULL lppaca to catch anyone using
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 57d2ffb2d45c..0dda4f8e3d7a 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -46,11 +46,10 @@ _GLOBAL(call_do_softirq)
 	mflr	r0
 	stw	r0,4(r1)
 	lwz	r10,THREAD+KSP_LIMIT(r2)
-	addi	r11,r3,THREAD_INFO_GAP
+	stw	r3, THREAD+KSP_LIMIT(r2)
 	stwu	r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
 	mr	r1,r3
 	stw	r10,8(r1)
-	stw	r11,THREAD+KSP_LIMIT(r2)
 	bl	__do_softirq
 	lwz	r10,8(r1)
 	lwz	r1,0(r1)
@@ -60,17 +59,16 @@ _GLOBAL(call_do_softirq)
 	blr
 
 /*
- * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp);
+ * void call_do_irq(struct pt_regs *regs, void *sp);
  */
 _GLOBAL(call_do_irq)
 	mflr	r0
 	stw	r0,4(r1)
 	lwz	r10,THREAD+KSP_LIMIT(r2)
-	addi	r11,r4,THREAD_INFO_GAP
+	stw	r4, THREAD+KSP_LIMIT(r2)
 	stwu	r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4)
 	mr	r1,r4
 	stw	r10,8(r1)
-	stw	r11,THREAD+KSP_LIMIT(r2)
 	bl	__do_irq
 	lwz	r10,8(r1)
 	lwz	r1,0(r1)
@@ -183,10 +181,13 @@ _GLOBAL(low_choose_750fx_pll)
 	or	r4,r4,r5
 	mtspr	SPRN_HID1,r4
 
+#ifdef CONFIG_SMP
 	/* Store new HID1 image */
-	CURRENT_THREAD_INFO(r6, r1)
-	lwz	r6,TI_CPU(r6)
+	lwz	r6,TASK_CPU(r2)
 	slwi	r6,r6,2
+#else
+	li	r6, 0
+#endif
 	addis	r6,r6,nap_save_hid1@ha
 	stw	r4,nap_save_hid1@l(r6)
 
@@ -599,7 +600,7 @@ EXPORT_SYMBOL(__bswapdi2)
 #ifdef CONFIG_SMP
 _GLOBAL(start_secondary_resume)
 	/* Reset stack */
-	CURRENT_THREAD_INFO(r1, r1)
+	rlwinm	r1, r1, 0, 0, 31 - THREAD_SHIFT
 	addi	r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
 	li	r3,0
 	stw	r3,0(r1)		/* Zero the stack frame pointer	*/
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index ce393df243aa..da82ab5dd743 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1231,8 +1231,8 @@ struct task_struct *__switch_to(struct task_struct *prev,
 		batch->active = 1;
 	}
 
-	if (current_thread_info()->task->thread.regs) {
-		restore_math(current_thread_info()->task->thread.regs);
+	if (current->thread.regs) {
+		restore_math(current->thread.regs);
 
 		/*
 		 * The copy-paste buffer can only store into foreign real
@@ -1242,7 +1242,7 @@ struct task_struct *__switch_to(struct task_struct *prev,
 		 * mappings, we must issue a cp_abort to clear any state and
 		 * prevent snooping, corruption or a covert channel.
 		 */
-		if (current_thread_info()->task->thread.used_vas)
+		if (current->thread.used_vas)
 			asm volatile(PPC_CP_ABORT);
 	}
 #endif /* CONFIG_PPC_BOOK3S_64 */
@@ -1634,7 +1634,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
 	struct thread_info *ti = task_thread_info(p);
 
-	klp_init_thread_info(ti);
+	klp_init_thread_info(p);
 
 	/* Copy registers */
 	sp -= sizeof(struct pt_regs);
@@ -1691,8 +1691,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	sp -= STACK_FRAME_OVERHEAD;
 	p->thread.ksp = sp;
 #ifdef CONFIG_PPC32
-	p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
-				_ALIGN_UP(sizeof(struct thread_info), 16);
+	p->thread.ksp_limit = (unsigned long)end_of_stack(p);
 #endif
 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 	p->thread.ptrace_bps[0] = NULL;
@@ -1995,21 +1994,14 @@ static inline int valid_irq_stack(unsigned long sp, struct task_struct *p,
 	unsigned long stack_page;
 	unsigned long cpu = task_cpu(p);
 
-	/*
-	 * Avoid crashing if the stack has overflowed and corrupted
-	 * task_cpu(p), which is in the thread_info struct.
-	 */
-	if (cpu < NR_CPUS && cpu_possible(cpu)) {
-		stack_page = (unsigned long) hardirq_ctx[cpu];
-		if (sp >= stack_page + sizeof(struct thread_struct)
-		    && sp <= stack_page + THREAD_SIZE - nbytes)
-			return 1;
-
-		stack_page = (unsigned long) softirq_ctx[cpu];
-		if (sp >= stack_page + sizeof(struct thread_struct)
-		    && sp <= stack_page + THREAD_SIZE - nbytes)
-			return 1;
-	}
+	stack_page = (unsigned long)hardirq_ctx[cpu];
+	if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes)
+		return 1;
+
+	stack_page = (unsigned long)softirq_ctx[cpu];
+	if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes)
+		return 1;
+
 	return 0;
 }
 
@@ -2018,8 +2010,10 @@ int validate_sp(unsigned long sp, struct task_struct *p,
 {
 	unsigned long stack_page = (unsigned long)task_stack_page(p);
 
-	if (sp >= stack_page + sizeof(struct thread_struct)
-	    && sp <= stack_page + THREAD_SIZE - nbytes)
+	if (sp < THREAD_SIZE)
+		return 0;
+
+	if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes)
 		return 1;
 
 	return valid_irq_stack(sp, p, nbytes);
@@ -2027,7 +2021,7 @@ int validate_sp(unsigned long sp, struct task_struct *p,
 
 EXPORT_SYMBOL(validate_sp);
 
-unsigned long get_wchan(struct task_struct *p)
+static unsigned long __get_wchan(struct task_struct *p)
 {
 	unsigned long ip, sp;
 	int count = 0;
@@ -2053,6 +2047,20 @@ unsigned long get_wchan(struct task_struct *p)
 	return 0;
 }
 
+unsigned long get_wchan(struct task_struct *p)
+{
+	unsigned long ret;
+
+	if (!try_get_task_stack(p))
+		return 0;
+
+	ret = __get_wchan(p);
+
+	put_task_stack(p);
+
+	return ret;
+}
+
 static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
 
 void show_stack(struct task_struct *tsk, unsigned long *stack)
@@ -2067,6 +2075,9 @@ void show_stack(struct task_struct *tsk, unsigned long *stack)
 	int curr_frame = 0;
 #endif
 
+	if (!try_get_task_stack(tsk))
+		return;
+
 	sp = (unsigned long) stack;
 	if (tsk == NULL)
 		tsk = current;
@@ -2081,7 +2092,7 @@ void show_stack(struct task_struct *tsk, unsigned long *stack)
 	printk("Call Trace:\n");
 	do {
 		if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
-			return;
+			break;
 
 		stack = (unsigned long *) sp;
 		newsp = stack[0];
@@ -2121,6 +2132,8 @@ void show_stack(struct task_struct *tsk, unsigned long *stack)
 
 		sp = newsp;
 	} while (count++ < kstack_depth_to_print);
+
+	put_task_stack(tsk);
 }
 
 #ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index ca00fbb97cf8..3d0dab1647fe 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -938,7 +938,7 @@ void __init setup_arch(char **cmdline_p)
 	/* Reserve large chunks of memory for use by CMA for KVM. */
 	kvm_cma_reserve();
 
-	klp_init_thread_info(&init_thread_info);
+	klp_init_thread_info(&init_task);
 
 	init_mm.start_code = (unsigned long)_stext;
 	init_mm.end_code = (unsigned long) _etext;
diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
index 947f904688b0..1f0b7629c1a6 100644
--- a/arch/powerpc/kernel/setup_32.c
+++ b/arch/powerpc/kernel/setup_32.c
@@ -196,6 +196,17 @@ static int __init ppc_init(void)
 }
 arch_initcall(ppc_init);
 
+static void *__init alloc_stack(void)
+{
+	void *ptr = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
+
+	if (!ptr)
+		panic("cannot allocate %d bytes for stack at %pS\n",
+		      THREAD_SIZE, (void *)_RET_IP_);
+
+	return ptr;
+}
+
 void __init irqstack_early_init(void)
 {
 	unsigned int i;
@@ -203,10 +214,8 @@ void __init irqstack_early_init(void)
 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
 	 * as the memblock is limited to lowmem by default */
 	for_each_possible_cpu(i) {
-		softirq_ctx[i] = (struct thread_info *)
-			__va(memblock_phys_alloc(THREAD_SIZE, THREAD_SIZE));
-		hardirq_ctx[i] = (struct thread_info *)
-			__va(memblock_phys_alloc(THREAD_SIZE, THREAD_SIZE));
+		softirq_ctx[i] = alloc_stack();
+		hardirq_ctx[i] = alloc_stack();
 	}
 }
 
@@ -224,13 +233,10 @@ void __init exc_lvl_early_init(void)
 		hw_cpu = 0;
 #endif
 
-		critirq_ctx[hw_cpu] = (struct thread_info *)
-			__va(memblock_phys_alloc(THREAD_SIZE, THREAD_SIZE));
+		critirq_ctx[hw_cpu] = alloc_stack();
 #ifdef CONFIG_BOOKE
-		dbgirq_ctx[hw_cpu] = (struct thread_info *)
-			__va(memblock_phys_alloc(THREAD_SIZE, THREAD_SIZE));
-		mcheckirq_ctx[hw_cpu] = (struct thread_info *)
-			__va(memblock_phys_alloc(THREAD_SIZE, THREAD_SIZE));
+		dbgirq_ctx[hw_cpu] = alloc_stack();
+		mcheckirq_ctx[hw_cpu] = alloc_stack();
 #endif
 	}
 }
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 236c1151a3a7..daa361fc6a24 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -634,19 +634,17 @@ __init u64 ppc64_bolted_size(void)
 
 static void *__init alloc_stack(unsigned long limit, int cpu)
 {
-	unsigned long pa;
+	void *ptr;
 
 	BUILD_BUG_ON(STACK_INT_FRAME_SIZE % 16);
 
-	pa = memblock_alloc_base_nid(THREAD_SIZE, THREAD_SIZE, limit,
-					early_cpu_to_node(cpu), MEMBLOCK_NONE);
-	if (!pa) {
-		pa = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
-		if (!pa)
-			panic("cannot allocate stacks");
-	}
+	ptr = memblock_alloc_try_nid(THREAD_SIZE, THREAD_SIZE,
+				     MEMBLOCK_LOW_LIMIT, limit,
+				     early_cpu_to_node(cpu));
+	if (!ptr)
+		panic("cannot allocate stacks");
 
-	return __va(pa);
+	return ptr;
 }
 
 void __init irqstack_early_init(void)
@@ -692,24 +690,6 @@ void __init exc_lvl_early_init(void)
 #endif
 
 /*
- * Emergency stacks are used for a range of things, from asynchronous
- * NMIs (system reset, machine check) to synchronous, process context.
- * We set preempt_count to zero, even though that isn't necessarily correct. To
- * get the right value we'd need to copy it from the previous thread_info, but
- * doing that might fault causing more problems.
- * TODO: what to do with accounting?
- */
-static void emerg_stack_init_thread_info(struct thread_info *ti, int cpu)
-{
-	ti->task = NULL;
-	ti->cpu = cpu;
-	ti->preempt_count = 0;
-	ti->local_flags = 0;
-	ti->flags = 0;
-	klp_init_thread_info(ti);
-}
-
-/*
  * Stack space used when we detect a bad kernel stack pointer, and
  * early in SMP boots before relocation is enabled. Exclusive emergency
  * stack for machine checks.
@@ -736,25 +716,14 @@ void __init emergency_stack_init(void)
 	limit = min(ppc64_bolted_size(), ppc64_rma_size);
 
 	for_each_possible_cpu(i) {
-		struct thread_info *ti;
-
-		ti = alloc_stack(limit, i);
-		memset(ti, 0, THREAD_SIZE);
-		emerg_stack_init_thread_info(ti, i);
-		paca_ptrs[i]->emergency_sp = (void *)ti + THREAD_SIZE;
+		paca_ptrs[i]->emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;
 
 #ifdef CONFIG_PPC_BOOK3S_64
 		/* emergency stack for NMI exception handling. */
-		ti = alloc_stack(limit, i);
-		memset(ti, 0, THREAD_SIZE);
-		emerg_stack_init_thread_info(ti, i);
-		paca_ptrs[i]->nmi_emergency_sp = (void *)ti + THREAD_SIZE;
+		paca_ptrs[i]->nmi_emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;
 
 		/* emergency stack for machine check exception handling. */
-		ti = alloc_stack(limit, i);
-		memset(ti, 0, THREAD_SIZE);
-		emerg_stack_init_thread_info(ti, i);
-		paca_ptrs[i]->mc_emergency_sp = (void *)ti + THREAD_SIZE;
+		paca_ptrs[i]->mc_emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;
 #endif
 	}
 }
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 3f15edf25a0d..a41fa8924004 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -20,6 +20,7 @@
 #include <linux/kernel.h>
 #include <linux/export.h>
 #include <linux/sched/mm.h>
+#include <linux/sched/task_stack.h>
 #include <linux/sched/topology.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
@@ -75,7 +76,7 @@
 static DEFINE_PER_CPU(int, cpu_state) = { 0 };
 #endif
 
-struct thread_info *secondary_ti;
+struct task_struct *secondary_current;
 bool has_big_cores;
 
 DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map);
@@ -663,7 +664,7 @@ void smp_send_stop(void)
 }
 #endif /* CONFIG_NMI_IPI */
 
-struct thread_info *current_set[NR_CPUS];
+struct task_struct *current_set[NR_CPUS];
 
 static void smp_store_cpu_info(int id)
 {
@@ -928,7 +929,7 @@ void smp_prepare_boot_cpu(void)
 	paca_ptrs[boot_cpuid]->__current = current;
 #endif
 	set_numa_node(numa_cpu_lookup_table[boot_cpuid]);
-	current_set[boot_cpuid] = task_thread_info(current);
+	current_set[boot_cpuid] = current;
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -1013,14 +1014,13 @@ static bool secondaries_inhibited(void)
 
 static void cpu_idle_thread_init(unsigned int cpu, struct task_struct *idle)
 {
-	struct thread_info *ti = task_thread_info(idle);
-
 #ifdef CONFIG_PPC64
 	paca_ptrs[cpu]->__current = idle;
-	paca_ptrs[cpu]->kstack = (unsigned long)ti + THREAD_SIZE - STACK_FRAME_OVERHEAD;
+	paca_ptrs[cpu]->kstack = (unsigned long)task_stack_page(idle) +
+				 THREAD_SIZE - STACK_FRAME_OVERHEAD;
 #endif
-	ti->cpu = cpu;
-	secondary_ti = current_set[cpu] = ti;
+	idle->cpu = cpu;
+	secondary_current = current_set[cpu] = idle;
 }
 
 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c
index cf31ce6c1f53..f958f3bcba04 100644
--- a/arch/powerpc/kernel/stacktrace.c
+++ b/arch/powerpc/kernel/stacktrace.c
@@ -67,12 +67,17 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
 {
 	unsigned long sp;
 
+	if (!try_get_task_stack(tsk))
+		return;
+
 	if (tsk == current)
 		sp = current_stack_pointer();
 	else
 		sp = tsk->thread.ksp;
 
 	save_context_stack(trace, sp, tsk, 0);
+
+	put_task_stack(tsk);
 }
 EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
 
@@ -90,9 +95,8 @@ EXPORT_SYMBOL_GPL(save_stack_trace_regs);
  *
  * If the task is not 'current', the caller *must* ensure the task is inactive.
  */
-int
-save_stack_trace_tsk_reliable(struct task_struct *tsk,
-				struct stack_trace *trace)
+static int __save_stack_trace_tsk_reliable(struct task_struct *tsk,
+					   struct stack_trace *trace)
 {
 	unsigned long sp;
 	unsigned long newsp;
@@ -197,6 +201,25 @@ save_stack_trace_tsk_reliable(struct task_struct *tsk,
 	}
 	return 0;
 }
+
+int save_stack_trace_tsk_reliable(struct task_struct *tsk,
+				  struct stack_trace *trace)
+{
+	int ret;
+
+	/*
+	 * If the task doesn't have a stack (e.g., a zombie), the stack is
+	 * "reliably" empty.
+	 */
+	if (!try_get_task_stack(tsk))
+		return 0;
+
+	ret = __save_stack_trace_tsk_reliable(tsk, trace);
+
+	put_task_stack(tsk);
+
+	return ret;
+}
 EXPORT_SYMBOL_GPL(save_stack_trace_tsk_reliable);
 #endif /* CONFIG_HAVE_RELIABLE_STACKTRACE */
 
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index 32476a6e4e9c..17ec02cb2f58 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -229,7 +229,7 @@ ftrace_call:
 	 *  - r0, r11 & r12 are free
 	 */
 livepatch_handler:
-	CURRENT_THREAD_INFO(r12, r1)
+	ld	r12, PACA_CURRENT_TI(r13)
 
 	/* Allocate 3 x 8 bytes */
 	ld	r11, TI_livepatch_sp(r12)
@@ -256,7 +256,7 @@ livepatch_handler:
 	 * restore it.
 	 */
 
-	CURRENT_THREAD_INFO(r12, r1)
+	ld	r12, PACA_CURRENT_TI(r13)
 
 	ld	r11, TI_livepatch_sp(r12)
 
@@ -273,7 +273,7 @@ livepatch_handler:
 	ld	r2,  -24(r11)
 
 	/* Pop livepatch stack frame */
-	CURRENT_THREAD_INFO(r12, r1)
+	ld	r12, PACA_CURRENT_TI(r13)
 	subi	r11, r11, 24
 	std	r11, TI_livepatch_sp(r12)
 
diff --git a/arch/powerpc/kvm/book3s_hv_hmi.c b/arch/powerpc/kvm/book3s_hv_hmi.c
index e3f738eb1cac..64b5011475c7 100644
--- a/arch/powerpc/kvm/book3s_hv_hmi.c
+++ b/arch/powerpc/kvm/book3s_hv_hmi.c
@@ -24,6 +24,7 @@
 #include <linux/compiler.h>
 #include <asm/paca.h>
 #include <asm/hmi.h>
+#include <asm/processor.h>
 
 void wait_for_subcore_guest_exit(void)
 {
diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S
index 1e2df3e9f9ea..5bee2d982959 100644
--- a/arch/powerpc/mm/hash_low_32.S
+++ b/arch/powerpc/mm/hash_low_32.S
@@ -186,8 +186,7 @@ _GLOBAL(add_hash_page)
 	add	r3,r3,r0		/* note create_hpte trims to 24 bits */
 
 #ifdef CONFIG_SMP
-	CURRENT_THREAD_INFO(r8, r1)	/* use cpu number to make tag */
-	lwz	r8,TI_CPU(r8)		/* to go in mmu_hash_lock */
+	lwz	r8,TASK_CPU(r2)		/* to go in mmu_hash_lock */
 	oris	r8,r8,12
 #endif /* CONFIG_SMP */
 
@@ -549,9 +548,8 @@ _GLOBAL(flush_hash_pages)
 #ifdef CONFIG_SMP
 	addis	r9,r7,mmu_hash_lock@ha
 	addi	r9,r9,mmu_hash_lock@l
-	CURRENT_THREAD_INFO(r8, r1)
-	add	r8,r8,r7
-	lwz	r8,TI_CPU(r8)
+	add	r8,r2,r7
+	lwz	r8,TASK_CPU(r8)
 	oris	r8,r8,9
 10:	lwarx	r0,0,r9
 	cmpi	0,r0,0
@@ -646,8 +644,7 @@ EXPORT_SYMBOL(flush_hash_pages)
  */
 _GLOBAL(_tlbie)
 #ifdef CONFIG_SMP
-	CURRENT_THREAD_INFO(r8, r1)
-	lwz	r8,TI_CPU(r8)
+	lwz	r8,TASK_CPU(r2)
 	oris	r8,r8,11
 	mfmsr	r10
 	SYNC
@@ -684,8 +681,7 @@ _GLOBAL(_tlbie)
  */
 _GLOBAL(_tlbia)
 #if defined(CONFIG_SMP)
-	CURRENT_THREAD_INFO(r8, r1)
-	lwz	r8,TI_CPU(r8)
+	lwz	r8,TASK_CPU(r2)
 	oris	r8,r8,10
 	mfmsr	r10
 	SYNC
diff --git a/arch/powerpc/net/bpf_jit32.h b/arch/powerpc/net/bpf_jit32.h
index 6f4daacad296..dc50a8d4b3b9 100644
--- a/arch/powerpc/net/bpf_jit32.h
+++ b/arch/powerpc/net/bpf_jit32.h
@@ -106,9 +106,8 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 	} while (0)
 #else
 #define PPC_BPF_LOAD_CPU(r)     \
-	do { BUILD_BUG_ON(FIELD_SIZEOF(struct thread_info, cpu) != 4);		\
-		PPC_LHZ_OFFS(r, (1 & ~(THREAD_SIZE - 1)),			\
-				offsetof(struct thread_info, cpu));		\
+	do { BUILD_BUG_ON(FIELD_SIZEOF(struct task_struct, cpu) != 4);		\
+		PPC_LHZ_OFFS(r, 2, offsetof(struct task_struct, cpu));		\
 	} while(0)
 #endif
 #else
diff --git a/arch/powerpc/sysdev/6xx-suspend.S b/arch/powerpc/sysdev/6xx-suspend.S
index cf48e9cb2575..6c4aec25c4ba 100644
--- a/arch/powerpc/sysdev/6xx-suspend.S
+++ b/arch/powerpc/sysdev/6xx-suspend.S
@@ -29,10 +29,9 @@ _GLOBAL(mpc6xx_enter_standby)
 	ori	r5, r5, ret_from_standby@l
 	mtlr	r5
 
-	CURRENT_THREAD_INFO(r5, r1)
-	lwz	r6, TI_LOCAL_FLAGS(r5)
+	lwz	r6, TI_LOCAL_FLAGS(r2)
 	ori	r6, r6, _TLF_SLEEPING
-	stw	r6, TI_LOCAL_FLAGS(r5)
+	stw	r6, TI_LOCAL_FLAGS(r2)
 
 	mfmsr	r5
 	ori	r5, r5, MSR_EE
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 757b8499aba2..a0f44f992360 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2997,7 +2997,7 @@ static void show_task(struct task_struct *tsk)
 	printf("%px %016lx %6d %6d %c %2d %s\n", tsk,
 		tsk->thread.ksp,
 		tsk->pid, rcu_dereference(tsk->parent)->pid,
-		state, task_thread_info(tsk)->cpu,
+		state, task_cpu(tsk),
 		tsk->comm);
 }
 
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 02/16] powerpc/32: Refactor EXCEPTION entry macros for head_8xx.S and head_32.S
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 01/16] powerpc: CONFIG_THREAD_INFO_IN_TASK series Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it Christophe Leroy
                   ` (13 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

EXCEPTION_PROLOG is similar in head_8xx.S and head_32.S

This patch creates head_32.h and moves EXCEPTION_PROLOG macro
into it. It also converts it from a GCC macro to a GAS macro
in order to ease refactorisation with 40x later, since
GAS macros allows the use of #ifdef/#else/#endif inside it.
And it also has the advantage of not requiring the uggly "; \"
at the end of each line.

This patch also moves EXCEPTION() and EXC_XFER_XXXX() macros which
are also similar while adding START_EXCEPTION() out of EXCEPTION().

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.S  |  99 +---------------------------------
 arch/powerpc/kernel/head_32.h  | 118 +++++++++++++++++++++++++++++++++++++++++
 arch/powerpc/kernel/head_8xx.S |  98 +---------------------------------
 3 files changed, 122 insertions(+), 193 deletions(-)
 create mode 100644 arch/powerpc/kernel/head_32.h

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 146385b1c2da..9410e5490c33 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -37,6 +37,8 @@
 #include <asm/export.h>
 #include <asm/feature-fixups.h>
 
+#include "head_32.h"
+
 /* 601 only have IBAT; cr0.eq is set on 601 when using this macro */
 #define LOAD_BAT(n, reg, RA, RB)	\
 	/* see the comment for clear_bats() -- Cort */ \
@@ -242,103 +244,6 @@ __secondary_hold_spinloop:
 __secondary_hold_acknowledge:
 	.long	-1
 
-/*
- * Exception entry code.  This code runs with address translation
- * turned off, i.e. using physical addresses.
- * We assume sprg3 has the physical address of the current
- * task's thread_struct.
- */
-#define EXCEPTION_PROLOG	\
-	mtspr	SPRN_SPRG_SCRATCH0,r10;	\
-	mtspr	SPRN_SPRG_SCRATCH1,r11;	\
-	mfcr	r10;		\
-	EXCEPTION_PROLOG_1;	\
-	EXCEPTION_PROLOG_2
-
-#define EXCEPTION_PROLOG_1	\
-	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel */ \
-	andi.	r11,r11,MSR_PR;	\
-	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
-	beq	1f;		\
-	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,TASK_STACK-THREAD(r11);	\
-	addi	r11,r11,THREAD_SIZE;	\
-	tophys(r11,r11);	\
-1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
-
-
-#define EXCEPTION_PROLOG_2	\
-	stw	r10,_CCR(r11);		/* save registers */ \
-	stw	r12,GPR12(r11);	\
-	stw	r9,GPR9(r11);	\
-	mfspr	r10,SPRN_SPRG_SCRATCH0;	\
-	stw	r10,GPR10(r11);	\
-	mfspr	r12,SPRN_SPRG_SCRATCH1;	\
-	stw	r12,GPR11(r11);	\
-	mflr	r10;		\
-	stw	r10,_LINK(r11);	\
-	mfspr	r12,SPRN_SRR0;	\
-	mfspr	r9,SPRN_SRR1;	\
-	stw	r1,GPR1(r11);	\
-	stw	r1,0(r11);	\
-	tovirt(r1,r11);			/* set new kernel sp */	\
-	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
-	MTMSRD(r10);			/* (except for mach check in rtas) */ \
-	stw	r0,GPR0(r11);	\
-	lis	r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
-	addi	r10,r10,STACK_FRAME_REGS_MARKER@l; \
-	stw	r10,8(r11);	\
-	SAVE_4GPRS(3, r11);	\
-	SAVE_2GPRS(7, r11)
-
-/*
- * Note: code which follows this uses cr0.eq (set if from kernel),
- * r11, r12 (SRR0), and r9 (SRR1).
- *
- * Note2: once we have set r1 we are in a position to take exceptions
- * again, and we could thus set MSR:RI at that point.
- */
-
-/*
- * Exception vectors.
- */
-#define EXCEPTION(n, label, hdlr, xfer)		\
-	. = n;					\
-	DO_KVM n;				\
-label:						\
-	EXCEPTION_PROLOG;			\
-	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
-	xfer(n, hdlr)
-
-#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
-	li	r10,trap;					\
-	stw	r10,_TRAP(r11);					\
-	li	r10,MSR_KERNEL;					\
-	copyee(r10, r9);					\
-	bl	tfer;						\
-i##n:								\
-	.long	hdlr;						\
-	.long	ret
-
-#define COPY_EE(d, s)		rlwimi d,s,0,16,16
-#define NOCOPY(d, s)
-
-#define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
-			  ret_from_except_full)
-
-#define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
-			  ret_from_except)
-
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
 /* System reset */
 /* core99 pmac starts the seconary here by changing the vector, and
    putting it back to what it was (unknown_exception) when done.  */
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
new file mode 100644
index 000000000000..7456e2a45acc
--- /dev/null
+++ b/arch/powerpc/kernel/head_32.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __HEAD_32_H__
+#define __HEAD_32_H__
+
+#include <asm/ptrace.h>	/* for STACK_FRAME_REGS_MARKER */
+
+/*
+ * Exception entry code.  This code runs with address translation
+ * turned off, i.e. using physical addresses.
+ * We assume sprg3 has the physical address of the current
+ * task's thread_struct.
+ */
+
+.macro EXCEPTION_PROLOG
+	mtspr	SPRN_SPRG_SCRATCH0,r10
+	mtspr	SPRN_SPRG_SCRATCH1,r11
+	mfcr	r10
+	EXCEPTION_PROLOG_1
+	EXCEPTION_PROLOG_2
+.endm
+
+.macro EXCEPTION_PROLOG_1
+	mfspr	r11,SPRN_SRR1		/* check whether user or kernel */
+	andi.	r11,r11,MSR_PR
+	tophys(r11,r1)			/* use tophys(r1) if kernel */
+	beq	1f
+	mfspr	r11,SPRN_SPRG_THREAD
+	lwz	r11,TASK_STACK-THREAD(r11)
+	addi	r11,r11,THREAD_SIZE
+	tophys(r11,r11)
+1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
+.endm
+
+.macro EXCEPTION_PROLOG_2
+	stw	r10,_CCR(r11)		/* save registers */
+	stw	r12,GPR12(r11)
+	stw	r9,GPR9(r11)
+	mfspr	r10,SPRN_SPRG_SCRATCH0
+	stw	r10,GPR10(r11)
+	mfspr	r12,SPRN_SPRG_SCRATCH1
+	stw	r12,GPR11(r11)
+	mflr	r10
+	stw	r10,_LINK(r11)
+	mfspr	r12,SPRN_SRR0
+	mfspr	r9,SPRN_SRR1
+	stw	r1,GPR1(r11)
+	stw	r1,0(r11)
+	tovirt(r1,r11)			/* set new kernel sp */
+	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR) /* can take exceptions */
+	MTMSRD(r10)			/* (except for mach check in rtas) */
+	stw	r0,GPR0(r11)
+	lis	r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
+	addi	r10,r10,STACK_FRAME_REGS_MARKER@l
+	stw	r10,8(r11)
+	SAVE_4GPRS(3, r11)
+	SAVE_2GPRS(7, r11)
+.endm
+
+/*
+ * Note: code which follows this uses cr0.eq (set if from kernel),
+ * r11, r12 (SRR0), and r9 (SRR1).
+ *
+ * Note2: once we have set r1 we are in a position to take exceptions
+ * again, and we could thus set MSR:RI at that point.
+ */
+
+/*
+ * Exception vectors.
+ */
+#ifdef CONFIG_PPC_BOOK3S
+#define	START_EXCEPTION(n, label)		\
+	. = n;					\
+	DO_KVM n;				\
+label:
+
+#else
+#define	START_EXCEPTION(n, label)		\
+	. = n;					\
+label:
+
+#endif
+
+#define EXCEPTION(n, label, hdlr, xfer)		\
+	START_EXCEPTION(n, label)		\
+	EXCEPTION_PROLOG;			\
+	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
+	xfer(n, hdlr)
+
+#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
+	li	r10,trap;					\
+	stw	r10,_TRAP(r11);					\
+	li	r10,MSR_KERNEL;					\
+	copyee(r10, r9);					\
+	bl	tfer;						\
+i##n:								\
+	.long	hdlr;						\
+	.long	ret
+
+#define COPY_EE(d, s)		rlwimi d,s,0,MSR_EE
+#define NOCOPY(d, s)
+
+#define EXC_XFER_STD(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
+			  ret_from_except_full)
+
+#define EXC_XFER_LITE(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
+			  ret_from_except)
+
+#define EXC_XFER_EE(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
+			  ret_from_except_full)
+
+#define EXC_XFER_EE_LITE(n, hdlr)	\
+	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
+			  ret_from_except)
+
+#endif /* __HEAD_32_H__ */
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index ca9207013579..083f27f383b4 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -33,6 +33,8 @@
 #include <asm/export.h>
 #include <asm/code-patching-asm.h>
 
+#include "head_32.h"
+
 #if CONFIG_TASK_SIZE <= 0x80000000 && CONFIG_PAGE_OFFSET >= 0x80000000
 /* By simply checking Address >= 0x80000000, we know if its a kernel address */
 #define SIMPLE_KERNEL_ADDRESS		1
@@ -123,102 +125,6 @@ instruction_counter:
 	.space	4
 #endif
 
-/*
- * Exception entry code.  This code runs with address translation
- * turned off, i.e. using physical addresses.
- * We assume sprg3 has the physical address of the current
- * task's thread_struct.
- */
-#define EXCEPTION_PROLOG	\
-	mtspr	SPRN_SPRG_SCRATCH0, r10;	\
-	mtspr	SPRN_SPRG_SCRATCH1, r11;	\
-	mfcr	r10;		\
-	EXCEPTION_PROLOG_1;	\
-	EXCEPTION_PROLOG_2
-
-#define EXCEPTION_PROLOG_1	\
-	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel */ \
-	andi.	r11,r11,MSR_PR;	\
-	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
-	beq	1f;		\
-	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,TASK_STACK-THREAD(r11);	\
-	addi	r11,r11,THREAD_SIZE;	\
-	tophys(r11,r11);	\
-1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
-
-
-#define EXCEPTION_PROLOG_2	\
-	stw	r10,_CCR(r11);		/* save registers */ \
-	stw	r12,GPR12(r11);	\
-	stw	r9,GPR9(r11);	\
-	mfspr	r10,SPRN_SPRG_SCRATCH0;	\
-	stw	r10,GPR10(r11);	\
-	mfspr	r12,SPRN_SPRG_SCRATCH1;	\
-	stw	r12,GPR11(r11);	\
-	mflr	r10;		\
-	stw	r10,_LINK(r11);	\
-	mfspr	r12,SPRN_SRR0;	\
-	mfspr	r9,SPRN_SRR1;	\
-	stw	r1,GPR1(r11);	\
-	stw	r1,0(r11);	\
-	tovirt(r1,r11);			/* set new kernel sp */	\
-	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
-	mtmsr	r10;		\
-	stw	r0,GPR0(r11);	\
-	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
-	addi	r10, r10, STACK_FRAME_REGS_MARKER@l; \
-	stw	r10, 8(r11);	\
-	SAVE_4GPRS(3, r11);	\
-	SAVE_2GPRS(7, r11)
-
-/*
- * Note: code which follows this uses cr0.eq (set if from kernel),
- * r11, r12 (SRR0), and r9 (SRR1).
- *
- * Note2: once we have set r1 we are in a position to take exceptions
- * again, and we could thus set MSR:RI at that point.
- */
-
-/*
- * Exception vectors.
- */
-#define EXCEPTION(n, label, hdlr, xfer)		\
-	. = n;					\
-label:						\
-	EXCEPTION_PROLOG;			\
-	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
-	xfer(n, hdlr)
-
-#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
-	li	r10,trap;					\
-	stw	r10,_TRAP(r11);					\
-	li	r10,MSR_KERNEL;					\
-	copyee(r10, r9);					\
-	bl	tfer;						\
-i##n:								\
-	.long	hdlr;						\
-	.long	ret
-
-#define COPY_EE(d, s)		rlwimi d,s,0,16,16
-#define NOCOPY(d, s)
-
-#define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
-			  ret_from_except_full)
-
-#define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
-			  ret_from_except)
-
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
 /* System reset */
 	EXCEPTION(0x100, Reset, system_reset_exception, EXC_XFER_STD)
 
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 01/16] powerpc: CONFIG_THREAD_INFO_IN_TASK series Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 02/16] powerpc/32: Refactor EXCEPTION entry macros for head_8xx.S and head_32.S Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-11  0:21   ` Benjamin Herrenschmidt
  2019-02-08 12:52 ` [PATCH v1 04/16] powerpc/32: make the 6xx/8xx EXC_XFER_TEMPLATE() similar to the 40x/booke one Christophe Leroy
                   ` (12 subsequent siblings)
  15 siblings, 1 reply; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

As preparation for using head_32.h for head_40x.S, move
LOAD_MSR_KERNEL() there and use it to load r10 with MSR_KERNEL value.

In the mean time, this patch modifies it so that it takes into account
the size of the passed value to determine if 'li' can be used or if
'lis/ori' is needed instead of using the size of MSR_KERNEL. This is
done by using gas macro.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/entry_32.S |  9 +--------
 arch/powerpc/kernel/head_32.h  | 15 ++++++++++++++-
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index a5e2d5585dcb..b489aebdc5c5 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -37,14 +37,7 @@
 #include <asm/feature-fixups.h>
 #include <asm/barrier.h>
 
-/*
- * MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE.
- */
-#if MSR_KERNEL >= 0x10000
-#define LOAD_MSR_KERNEL(r, x)	lis r,(x)@h; ori r,r,(x)@l
-#else
-#define LOAD_MSR_KERNEL(r, x)	li r,(x)
-#endif
+#include "head_32.h"
 
 /*
  * Align to 4k in order to ensure that all functions modyfing srr0/srr1
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 7456e2a45acc..cf3d00844597 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -5,6 +5,19 @@
 #include <asm/ptrace.h>	/* for STACK_FRAME_REGS_MARKER */
 
 /*
+ * MSR_KERNEL is > 0x8000 on 4xx/Book-E since it include MSR_CE.
+ */
+.macro __LOAD_MSR_KERNEL r, x
+.if \x >= 0x8000
+	lis \r, (\x)@h
+	ori \r, \r, (\x)@l
+.else
+	li \r, (\x)
+.endif
+.endm
+#define LOAD_MSR_KERNEL(r, x) __LOAD_MSR_KERNEL r, x
+
+/*
  * Exception entry code.  This code runs with address translation
  * turned off, i.e. using physical addresses.
  * We assume sprg3 has the physical address of the current
@@ -89,7 +102,7 @@
 #define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
 	li	r10,trap;					\
 	stw	r10,_TRAP(r11);					\
-	li	r10,MSR_KERNEL;					\
+	LOAD_MSR_KERNEL(r10, MSR_KERNEL);			\
 	copyee(r10, r9);					\
 	bl	tfer;						\
 i##n:								\
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 04/16] powerpc/32: make the 6xx/8xx EXC_XFER_TEMPLATE() similar to the 40x/booke one
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (2 preceding siblings ...)
  2019-02-08 12:52 ` [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 05/16] powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG Christophe Leroy
                   ` (11 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

6xx/8xx EXC_XFER_TEMPLATE() macro adds a i##n symbol which is
unused and can be removed.
40x and booke EXC_XFER_TEMPLATE() macros takes msr from the caller
while the 6xx/8xx version uses only MSR_KERNEL as msr value.

This patch modifies the 6xx/8xx version to make it similar to the
40x and booke versions.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.h | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index cf3d00844597..985758cbf577 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -99,13 +99,12 @@
 	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
 	xfer(n, hdlr)
 
-#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
+#define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret)	\
 	li	r10,trap;					\
 	stw	r10,_TRAP(r11);					\
-	LOAD_MSR_KERNEL(r10, MSR_KERNEL);			\
+	LOAD_MSR_KERNEL(r10, msr);				\
 	copyee(r10, r9);					\
 	bl	tfer;						\
-i##n:								\
 	.long	hdlr;						\
 	.long	ret
 
@@ -113,19 +112,19 @@ i##n:								\
 #define NOCOPY(d, s)
 
 #define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
+	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full,	\
 			  ret_from_except_full)
 
 #define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
 			  ret_from_except)
 
 #define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
+	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
 			  ret_from_except_full)
 
 #define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
 			  ret_from_except)
 
 #endif /* __HEAD_32_H__ */
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 05/16] powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (3 preceding siblings ...)
  2019-02-08 12:52 ` [PATCH v1 04/16] powerpc/32: make the 6xx/8xx EXC_XFER_TEMPLATE() similar to the 40x/booke one Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 06/16] powerpc/40x: add exception frame marker Christophe Leroy
                   ` (10 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

Unlike said in the comment, r1 is not reused by the critical
exception handler, as it uses a dedicated critirq_ctx stack.
Decrementing r1 early is then unneeded.

Should the above be valid, the code is crap buggy anyway as
r1 gets some intermediate values that would jeopardise the
whole process (for instance after mfspr   r1,SPRN_SPRG_THREAD)

Using SPRN_SPRG_SCRATCH2 to save r1 is then not needed, r11 can be
used instead. This avoids one mtspr and one mfspr and makes the
prolog closer to what's done on 6xx and 8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 3088c9f29f5e..59f6f53f1ac2 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -102,23 +102,20 @@ _ENTRY(saved_ksp_limit)
  * Exception vector entry code. This code runs with address translation
  * turned off (i.e. using physical addresses). We assume SPRG_THREAD has
  * the physical address of the current task thread_struct.
- * Note that we have to have decremented r1 before we write to any fields
- * of the exception frame, since a critical interrupt could occur at any
- * time, and it will write to the area immediately below the current r1.
  */
 #define NORMAL_EXCEPTION_PROLOG						     \
 	mtspr	SPRN_SPRG_SCRATCH0,r10;	/* save two registers to work with */\
 	mtspr	SPRN_SPRG_SCRATCH1,r11;					     \
-	mtspr	SPRN_SPRG_SCRATCH2,r1;					     \
 	mfcr	r10;			/* save CR in r10 for now	   */\
 	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel    */\
 	andi.	r11,r11,MSR_PR;						     \
-	beq	1f;							     \
-	mfspr	r1,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r1,TASK_STACK-THREAD(r1); /* this thread's kernel stack   */\
-	addi	r1,r1,THREAD_SIZE;					     \
-1:	subi	r1,r1,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
 	tophys(r11,r1);							     \
+	beq	1f;							     \
+	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
+	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
+	addi	r11,r11,THREAD_SIZE;					     \
+	tophys(r11,r11);						     \
+1:	subi	r11,r11,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
 	stw	r10,_CCR(r11);          /* save various registers	   */\
 	stw	r12,GPR12(r11);						     \
 	stw	r9,GPR9(r11);						     \
@@ -128,11 +125,11 @@ _ENTRY(saved_ksp_limit)
 	stw	r12,GPR11(r11);						     \
 	mflr	r10;							     \
 	stw	r10,_LINK(r11);						     \
-	mfspr	r10,SPRN_SPRG_SCRATCH2;					     \
 	mfspr	r12,SPRN_SRR0;						     \
-	stw	r10,GPR1(r11);						     \
+	stw	r1,GPR1(r11);						     \
 	mfspr	r9,SPRN_SRR1;						     \
-	stw	r10,0(r11);						     \
+	stw	r1,0(r11);						     \
+	tovirt(r1,r11);			/* set new kernel sp */	\
 	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
 	stw	r0,GPR0(r11);						     \
 	SAVE_4GPRS(3, r11);						     \
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 06/16] powerpc/40x: add exception frame marker
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (4 preceding siblings ...)
  2019-02-08 12:52 ` [PATCH v1 05/16] powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 07/16] powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG Christophe Leroy
                   ` (9 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

This patch adds STACK_FRAME_REGS_MARKER in the stack at exception entry
in order to see interrupts in call traces as below:

[    0.013964] Call Trace:
[    0.014014] [c0745db0] [c007a9d4] tick_periodic.constprop.5+0xd8/0x104 (unreliable)
[    0.014086] [c0745dc0] [c007aa20] tick_handle_periodic+0x20/0x9c
[    0.014181] [c0745de0] [c0009cd0] timer_interrupt+0xa0/0x264
[    0.014258] [c0745e10] [c000e484] ret_from_except+0x0/0x14
[    0.014390] --- interrupt: 901 at console_unlock.part.7+0x3f4/0x528
[    0.014390]     LR = console_unlock.part.7+0x3f0/0x528
[    0.014455] [c0745ee0] [c0050334] console_unlock.part.7+0x114/0x528 (unreliable)
[    0.014542] [c0745f30] [c00524e0] register_console+0x3d8/0x44c
[    0.014625] [c0745f60] [c0675aac] cpm_uart_console_init+0x18/0x2c
[    0.014709] [c0745f70] [c06614f4] console_init+0x114/0x1cc
[    0.014795] [c0745fb0] [c0658b68] start_kernel+0x300/0x3d8
[    0.014864] [c0745ff0] [c00022cc] start_here+0x44/0x98

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 59f6f53f1ac2..f3bfb695f952 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -132,6 +132,9 @@ _ENTRY(saved_ksp_limit)
 	tovirt(r1,r11);			/* set new kernel sp */	\
 	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
 	stw	r0,GPR0(r11);						     \
+	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */\
+	addi	r10, r10, STACK_FRAME_REGS_MARKER@l;			     \
+	stw	r10, 8(r11);						     \
 	SAVE_4GPRS(3, r11);						     \
 	SAVE_2GPRS(7, r11)
 
@@ -174,6 +177,9 @@ _ENTRY(saved_ksp_limit)
 	tovirt(r1,r11);							     \
 	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
 	stw	r0,GPR0(r11);						     \
+	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */\
+	addi	r10, r10, STACK_FRAME_REGS_MARKER@l;			     \
+	stw	r10, 8(r11);						     \
 	SAVE_4GPRS(3, r11);						     \
 	SAVE_2GPRS(7, r11)
 
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 07/16] powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (5 preceding siblings ...)
  2019-02-08 12:52 ` [PATCH v1 06/16] powerpc/40x: add exception frame marker Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [PATCH v1 08/16] powerpc/40x: Refactor exception entry macros by using head_32.h Christophe Leroy
                   ` (8 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

This patch splits NORMAL_EXCEPTION_PROLOG in the same way as in
head_8xx.S and head_32.S and renames it EXCEPTION_PROLOG() as well
to match head_32.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index f3bfb695f952..2961e2aa1d18 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -103,10 +103,14 @@ _ENTRY(saved_ksp_limit)
  * turned off (i.e. using physical addresses). We assume SPRG_THREAD has
  * the physical address of the current task thread_struct.
  */
-#define NORMAL_EXCEPTION_PROLOG						     \
+#define EXCEPTION_PROLOG						     \
 	mtspr	SPRN_SPRG_SCRATCH0,r10;	/* save two registers to work with */\
 	mtspr	SPRN_SPRG_SCRATCH1,r11;					     \
 	mfcr	r10;			/* save CR in r10 for now	   */\
+	EXCEPTION_PROLOG_1;						     \
+	EXCEPTION_PROLOG_2
+
+#define EXCEPTION_PROLOG_1						     \
 	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel    */\
 	andi.	r11,r11,MSR_PR;						     \
 	tophys(r11,r1);							     \
@@ -115,7 +119,9 @@ _ENTRY(saved_ksp_limit)
 	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
 	addi	r11,r11,THREAD_SIZE;					     \
 	tophys(r11,r11);						     \
-1:	subi	r11,r11,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
+1:	subi	r11,r11,INT_FRAME_SIZE	/* Allocate an exception frame     */
+
+#define EXCEPTION_PROLOG_2						     \
 	stw	r10,_CCR(r11);          /* save various registers	   */\
 	stw	r12,GPR12(r11);						     \
 	stw	r9,GPR9(r11);						     \
@@ -205,7 +211,7 @@ label:
 
 #define EXCEPTION(n, label, hdlr, xfer)				\
 	START_EXCEPTION(n, label);				\
-	NORMAL_EXCEPTION_PROLOG;				\
+	EXCEPTION_PROLOG;				\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
 	xfer(n, hdlr)
 
@@ -396,7 +402,7 @@ label:
  * This is caused by a fetch from non-execute or guarded pages.
  */
 	START_EXCEPTION(0x0400, InstructionAccess)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mr	r4,r12			/* Pass SRR0 as arg2 */
 	li	r5,0			/* Pass zero as arg3 */
 	EXC_XFER_LITE(0x400, handle_page_fault)
@@ -406,7 +412,7 @@ label:
 
 /* 0x0600 - Alignment Exception */
 	START_EXCEPTION(0x0600, Alignment)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mfspr	r4,SPRN_DEAR		/* Grab the DEAR and save it */
 	stw	r4,_DEAR(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -414,7 +420,7 @@ label:
 
 /* 0x0700 - Program Exception */
 	START_EXCEPTION(0x0700, ProgramCheck)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mfspr	r4,SPRN_ESR		/* Grab the ESR and save it */
 	stw	r4,_ESR(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -427,7 +433,7 @@ label:
 
 /* 0x0C00 - System Call Exception */
 	START_EXCEPTION(0x0C00,	SystemCall)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	EXC_XFER_EE_LITE(0xc00, DoSyscall)
 
 	EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_EE)
@@ -733,7 +739,7 @@ label:
 
 	/* Programmable Interval Timer (PIT) Exception. (from 0x1000) */
 Decrementer:
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	lis	r0,TSR_PIS@h
 	mtspr	SPRN_TSR,r0		/* Clear the PIT exception */
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -741,7 +747,7 @@ Decrementer:
 
 	/* Fixed Interval Timer (FIT) Exception. (from 0x1010) */
 FITException:
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	addi	r3,r1,STACK_FRAME_OVERHEAD;
 	EXC_XFER_EE(0x1010, unknown_exception)
 
@@ -759,7 +765,7 @@ WDTException:
  * if they can't resolve the lightweight TLB fault.
  */
 DataAccess:
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mfspr	r5,SPRN_ESR		/* Grab the ESR, save it, pass arg3 */
 	stw	r5,_ESR(r11)
 	mfspr	r4,SPRN_DEAR		/* Grab the DEAR, save it, pass arg2 */
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v1 08/16] powerpc/40x: Refactor exception entry macros by using head_32.h
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (6 preceding siblings ...)
  2019-02-08 12:52 ` [PATCH v1 07/16] powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 09/16] powerpc/fsl_booke: ensure SPEFloatingPointException() reenables interrupts Christophe Leroy
                   ` (7 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

Refactor exception entry macros by using the ones defined in head_32.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.h  |  4 ++
 arch/powerpc/kernel/head_40x.S | 88 +-----------------------------------------
 2 files changed, 6 insertions(+), 86 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 985758cbf577..aa0131bb09b5 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -59,8 +59,12 @@
 	stw	r1,GPR1(r11)
 	stw	r1,0(r11)
 	tovirt(r1,r11)			/* set new kernel sp */
+#ifdef CONFIG_40x
+	rlwinm	r9,r9,0,14,12		/* clear MSR_WE (necessary?) */
+#else
 	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR) /* can take exceptions */
 	MTMSRD(r10)			/* (except for mach check in rtas) */
+#endif
 	stw	r0,GPR0(r11)
 	lis	r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
 	addi	r10,r10,STACK_FRAME_REGS_MARKER@l
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 2961e2aa1d18..3dc8a35849ff 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -44,6 +44,8 @@
 #include <asm/export.h>
 #include <asm/asm-405.h>
 
+#include "head_32.h"
+
 /* As with the other PowerPC ports, it is expected that when code
  * execution begins here, the following registers contain valid, yet
  * optional, information:
@@ -99,52 +101,6 @@ _ENTRY(saved_ksp_limit)
 	.space	4
 
 /*
- * Exception vector entry code. This code runs with address translation
- * turned off (i.e. using physical addresses). We assume SPRG_THREAD has
- * the physical address of the current task thread_struct.
- */
-#define EXCEPTION_PROLOG						     \
-	mtspr	SPRN_SPRG_SCRATCH0,r10;	/* save two registers to work with */\
-	mtspr	SPRN_SPRG_SCRATCH1,r11;					     \
-	mfcr	r10;			/* save CR in r10 for now	   */\
-	EXCEPTION_PROLOG_1;						     \
-	EXCEPTION_PROLOG_2
-
-#define EXCEPTION_PROLOG_1						     \
-	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel    */\
-	andi.	r11,r11,MSR_PR;						     \
-	tophys(r11,r1);							     \
-	beq	1f;							     \
-	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
-	addi	r11,r11,THREAD_SIZE;					     \
-	tophys(r11,r11);						     \
-1:	subi	r11,r11,INT_FRAME_SIZE	/* Allocate an exception frame     */
-
-#define EXCEPTION_PROLOG_2						     \
-	stw	r10,_CCR(r11);          /* save various registers	   */\
-	stw	r12,GPR12(r11);						     \
-	stw	r9,GPR9(r11);						     \
-	mfspr	r10,SPRN_SPRG_SCRATCH0;					     \
-	stw	r10,GPR10(r11);						     \
-	mfspr	r12,SPRN_SPRG_SCRATCH1;					     \
-	stw	r12,GPR11(r11);						     \
-	mflr	r10;							     \
-	stw	r10,_LINK(r11);						     \
-	mfspr	r12,SPRN_SRR0;						     \
-	stw	r1,GPR1(r11);						     \
-	mfspr	r9,SPRN_SRR1;						     \
-	stw	r1,0(r11);						     \
-	tovirt(r1,r11);			/* set new kernel sp */	\
-	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
-	stw	r0,GPR0(r11);						     \
-	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */\
-	addi	r10, r10, STACK_FRAME_REGS_MARKER@l;			     \
-	stw	r10, 8(r11);						     \
-	SAVE_4GPRS(3, r11);						     \
-	SAVE_2GPRS(7, r11)
-
-/*
  * Exception prolog for critical exceptions.  This is a little different
  * from the normal exception prolog above since a critical exception
  * can potentially occur at any point during normal exception processing.
@@ -205,16 +161,6 @@ _ENTRY(saved_ksp_limit)
 /*
  * Exception vectors.
  */
-#define	START_EXCEPTION(n, label)					     \
-	. = n;								     \
-label:
-
-#define EXCEPTION(n, label, hdlr, xfer)				\
-	START_EXCEPTION(n, label);				\
-	EXCEPTION_PROLOG;				\
-	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
-	xfer(n, hdlr)
-
 #define CRITICAL_EXCEPTION(n, label, hdlr)			\
 	START_EXCEPTION(n, label);				\
 	CRITICAL_EXCEPTION_PROLOG;				\
@@ -223,36 +169,6 @@ label:
 			  NOCOPY, crit_transfer_to_handler,	\
 			  ret_from_crit_exc)
 
-#define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret)	\
-	li	r10,trap;					\
-	stw	r10,_TRAP(r11);					\
-	lis	r10,msr@h;					\
-	ori	r10,r10,msr@l;					\
-	copyee(r10, r9);					\
-	bl	tfer;		 				\
-	.long	hdlr;						\
-	.long	ret
-
-#define COPY_EE(d, s)		rlwimi d,s,0,16,16
-#define NOCOPY(d, s)
-
-#define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
-			  ret_from_except)
-
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
-
 /*
  * 0x0100 - Critical Interrupt Exception
  */
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 09/16] powerpc/fsl_booke: ensure SPEFloatingPointException() reenables interrupts
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (7 preceding siblings ...)
  2019-02-08 12:52 ` [PATCH v1 08/16] powerpc/40x: Refactor exception entry macros by using head_32.h Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 10/16] powerpc/32: enter syscall with MSR_EE inconditionaly set Christophe Leroy
                   ` (6 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

SPEFloatingPointException() is the only exception handler which 'forgets' to
re-enable interrupts. This patch makes sure it does.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/traps.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 040b60293613..ea552793fe44 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1997,6 +1997,10 @@ void SPEFloatingPointException(struct pt_regs *regs)
 	int code = FPE_FLTUNK;
 	int err;
 
+	/* We restore the interrupt state now */
+	if (!arch_irq_disabled_regs(regs))
+		local_irq_enable();
+
 	flush_spe_to_thread(current);
 
 	spefscr = current->thread.spefscr;
@@ -2042,6 +2046,10 @@ void SPEFloatingPointRoundException(struct pt_regs *regs)
 	extern int speround_handler(struct pt_regs *regs);
 	int err;
 
+	/* We restore the interrupt state now */
+	if (!arch_irq_disabled_regs(regs))
+		local_irq_enable();
+
 	preempt_disable();
 	if (regs->msr & MSR_SPE)
 		giveup_spe(current);
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 10/16] powerpc/32: enter syscall with MSR_EE inconditionaly set
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (8 preceding siblings ...)
  2019-02-08 12:52 ` [RFC PATCH v1 09/16] powerpc/fsl_booke: ensure SPEFloatingPointException() reenables interrupts Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 11/16] powerpc/32: Enter exceptions with MSR_EE unset Christophe Leroy
                   ` (5 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

syscalls are expected to be entered with MSR_EE set. Lets
make it inconditional by forcing MSR_EE on syscalls.

This patch adds EXC_XFER_SYS for that.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[splited out from benh RFC patch]

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.S        | 2 +-
 arch/powerpc/kernel/head_32.h        | 4 ++++
 arch/powerpc/kernel/head_40x.S       | 2 +-
 arch/powerpc/kernel/head_44x.S       | 2 +-
 arch/powerpc/kernel/head_8xx.S       | 2 +-
 arch/powerpc/kernel/head_booke.h     | 4 ++++
 arch/powerpc/kernel/head_fsl_booke.S | 2 +-
 7 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 9410e5490c33..33fb08b2398f 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -369,7 +369,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
 	DO_KVM  0xc00
 SystemCall:
 	EXCEPTION_PROLOG
-	EXC_XFER_EE_LITE(0xc00, DoSyscall)
+	EXC_XFER_SYS(0xc00, DoSyscall)
 
 /* Single step - not used on 601 */
 	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index aa0131bb09b5..7221418a883f 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -123,6 +123,10 @@
 	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
 			  ret_from_except)
 
+#define EXC_XFER_SYS(n, hdlr)		\
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, NOCOPY, transfer_to_handler, \
+			  ret_from_except)
+
 #define EXC_XFER_EE(n, hdlr)		\
 	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
 			  ret_from_except_full)
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 3dc8a35849ff..ee6edf8a20c2 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -350,7 +350,7 @@ _ENTRY(saved_ksp_limit)
 /* 0x0C00 - System Call Exception */
 	START_EXCEPTION(0x0C00,	SystemCall)
 	EXCEPTION_PROLOG
-	EXC_XFER_EE_LITE(0xc00, DoSyscall)
+	EXC_XFER_SYS(0xc00, DoSyscall)
 
 	EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_EE)
 	EXCEPTION(0x0E00, Trap_0E, unknown_exception, EXC_XFER_EE)
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S
index 37117ab11584..9cc01948651f 100644
--- a/arch/powerpc/kernel/head_44x.S
+++ b/arch/powerpc/kernel/head_44x.S
@@ -283,7 +283,7 @@ interrupt_base:
 	/* System Call Interrupt */
 	START_EXCEPTION(SystemCall)
 	NORMAL_EXCEPTION_PROLOG(BOOKE_INTERRUPT_SYSCALL)
-	EXC_XFER_EE_LITE(0x0c00, DoSyscall)
+	EXC_XFER_SYS(0x0c00, DoSyscall)
 
 	/* Auxiliary Processor Unavailable Interrupt */
 	EXCEPTION(0x2020, BOOKE_INTERRUPT_AP_UNAVAIL, \
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 083f27f383b4..dfd5a8195e5e 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -186,7 +186,7 @@ Alignment:
 	. = 0xc00
 SystemCall:
 	EXCEPTION_PROLOG
-	EXC_XFER_EE_LITE(0xc00, DoSyscall)
+	EXC_XFER_SYS(0xc00, DoSyscall)
 
 /* Single step - not used on 601 */
 	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index 1b22a8dea399..612f54ba1125 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -251,6 +251,10 @@ END_BTB_FLUSH_SECTION
 	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
 			  ret_from_except)
 
+#define EXC_XFER_SYS(n, hdlr)						\
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, NOCOPY, transfer_to_handler, \
+			  ret_from_except)
+
 #define EXC_XFER_EE(n, hdlr)		\
 	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
 			  ret_from_except_full)
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 1881127682e9..89f36623993d 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -418,7 +418,7 @@ interrupt_base:
 	/* System Call Interrupt */
 	START_EXCEPTION(SystemCall)
 	NORMAL_EXCEPTION_PROLOG(SYSCALL)
-	EXC_XFER_EE_LITE(0x0c00, DoSyscall)
+	EXC_XFER_SYS(0x0c00, DoSyscall)
 
 	/* Auxiliary Processor Unavailable Interrupt */
 	EXCEPTION(0x2900, AP_UNAVAIL, AuxillaryProcessorUnavailable, \
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 11/16] powerpc/32: Enter exceptions with MSR_EE unset
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (9 preceding siblings ...)
  2019-02-08 12:52 ` [RFC PATCH v1 10/16] powerpc/32: enter syscall with MSR_EE inconditionaly set Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 12/16] powerpc/32: get rid of COPY_EE in exception entry Christophe Leroy
                   ` (4 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

All exceptions handler knows when to reenable interrupts, so
it is safer to enter all of them with MSR_EE unset, except
for syscalls.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[splited out from benh RFC patch]

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.S        | 68 ++++++++++++++++++------------------
 arch/powerpc/kernel/head_32.h        |  8 -----
 arch/powerpc/kernel/head_40x.S       | 44 +++++++++++------------
 arch/powerpc/kernel/head_44x.S       |  6 ++--
 arch/powerpc/kernel/head_8xx.S       | 32 ++++++++---------
 arch/powerpc/kernel/head_booke.h     | 12 ++-----
 arch/powerpc/kernel/head_fsl_booke.S | 26 +++++++-------
 7 files changed, 90 insertions(+), 106 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 33fb08b2398f..3a1df9edf6da 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -335,7 +335,7 @@ Alignment:
 	mfspr	r5,SPRN_DSISR
 	stw	r5,_DSISR(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_EE(0x600, alignment_exception)
+	EXC_XFER_STD(0x600, alignment_exception)
 
 /* Program check exception */
 	EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
@@ -356,13 +356,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
 	bl	load_up_fpu		/* if from user, just load it up */
 	b	fast_exception_return
 1:	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
+	EXC_XFER_LITE(0x800, kernel_fp_unavailable_exception)
 
 /* Decrementer */
 	EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE)
 
-	EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_STD)
 
 /* System call */
 	. = 0xc00
@@ -373,7 +373,7 @@ SystemCall:
 
 /* Single step - not used on 601 */
 	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
-	EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_STD)
 
 /*
  * The Altivec unavailable trap is at 0x0f20.  Foo.
@@ -617,35 +617,35 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
 #define altivec_assist_exception	unknown_exception
 #endif
 
-	EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception, EXC_XFER_EE)
-	EXCEPTION(0x1400, SMI, SMIException, EXC_XFER_EE)
-	EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1600, Trap_16, altivec_assist_exception, EXC_XFER_EE)
+	EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception, EXC_XFER_STD)
+	EXCEPTION(0x1400, SMI, SMIException, EXC_XFER_STD)
+	EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1600, Trap_16, altivec_assist_exception, EXC_XFER_STD)
 	EXCEPTION(0x1700, Trap_17, TAUException, EXC_XFER_STD)
-	EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1c00, Trap_1c, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2000, RunMode, RunModeException, EXC_XFER_EE)
-	EXCEPTION(0x2100, Trap_21, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2200, Trap_22, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2300, Trap_23, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2400, Trap_24, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2500, Trap_25, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2600, Trap_26, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2700, Trap_27, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2800, Trap_28, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2900, Trap_29, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2a00, Trap_2a, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2b00, Trap_2b, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2c00, Trap_2c, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2d00, Trap_2d, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2e00, Trap_2e, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x2f00, Trap_2f, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1c00, Trap_1c, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2000, RunMode, RunModeException, EXC_XFER_STD)
+	EXCEPTION(0x2100, Trap_21, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2200, Trap_22, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2300, Trap_23, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2400, Trap_24, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2500, Trap_25, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2600, Trap_26, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2700, Trap_27, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2800, Trap_28, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2900, Trap_29, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2a00, Trap_2a, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2b00, Trap_2b, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2c00, Trap_2c, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2d00, Trap_2d, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2e00, Trap_2e, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x2f00, Trap_2f, unknown_exception, EXC_XFER_STD)
 
 	. = 0x3000
 
@@ -657,7 +657,7 @@ AltiVecUnavailable:
 	b	fast_exception_return
 #endif /* CONFIG_ALTIVEC */
 1:	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_EE_LITE(0xf20, altivec_unavailable_exception)
+	EXC_XFER_LITE(0xf20, altivec_unavailable_exception)
 
 PerformanceMonitor:
 	EXCEPTION_PROLOG
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 7221418a883f..8881b6887841 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -127,12 +127,4 @@
 	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, NOCOPY, transfer_to_handler, \
 			  ret_from_except)
 
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
 #endif /* __HEAD_32_H__ */
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index ee6edf8a20c2..549db4fed183 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -332,7 +332,7 @@ _ENTRY(saved_ksp_limit)
 	mfspr	r4,SPRN_DEAR		/* Grab the DEAR and save it */
 	stw	r4,_DEAR(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_EE(0x600, alignment_exception)
+	EXC_XFER_STD(0x600, alignment_exception)
 
 /* 0x0700 - Program Exception */
 	START_EXCEPTION(0x0700, ProgramCheck)
@@ -342,19 +342,19 @@ _ENTRY(saved_ksp_limit)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	EXC_XFER_STD(0x700, program_check_exception)
 
-	EXCEPTION(0x0800, Trap_08, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x0900, Trap_09, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x0A00, Trap_0A, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x0B00, Trap_0B, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x0800, Trap_08, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x0900, Trap_09, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x0A00, Trap_0A, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x0B00, Trap_0B, unknown_exception, EXC_XFER_STD)
 
 /* 0x0C00 - System Call Exception */
 	START_EXCEPTION(0x0C00,	SystemCall)
 	EXCEPTION_PROLOG
 	EXC_XFER_SYS(0xc00, DoSyscall)
 
-	EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x0E00, Trap_0E, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x0F00, Trap_0F, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x0E00, Trap_0E, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x0F00, Trap_0F, unknown_exception, EXC_XFER_STD)
 
 /* 0x1000 - Programmable Interval Timer (PIT) Exception */
 	. = 0x1000
@@ -571,25 +571,25 @@ _ENTRY(saved_ksp_limit)
 	mfspr	r10, SPRN_SPRG_SCRATCH0
 	b	InstructionAccess
 
-	EXCEPTION(0x1300, Trap_13, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1400, Trap_14, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1600, Trap_16, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1300, Trap_13, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1400, Trap_14, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1600, Trap_16, unknown_exception, EXC_XFER_STD)
 #ifdef CONFIG_IBM405_ERR51
 	/* 405GP errata 51 */
 	START_EXCEPTION(0x1700, Trap_17)
 	b DTLBMiss
 #else
-	EXCEPTION(0x1700, Trap_17, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1700, Trap_17, unknown_exception, EXC_XFER_STD)
 #endif
-	EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1A00, Trap_1A, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1B00, Trap_1B, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1C00, Trap_1C, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1D00, Trap_1D, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1E00, Trap_1E, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1F00, Trap_1F, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1A00, Trap_1A, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1B00, Trap_1B, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1C00, Trap_1C, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1D00, Trap_1D, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1E00, Trap_1E, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1F00, Trap_1F, unknown_exception, EXC_XFER_STD)
 
 /* Check for a single step debug exception while in an exception
  * handler before state has been saved.  This is to catch the case
@@ -665,7 +665,7 @@ Decrementer:
 FITException:
 	EXCEPTION_PROLOG
 	addi	r3,r1,STACK_FRAME_OVERHEAD;
-	EXC_XFER_EE(0x1010, unknown_exception)
+	EXC_XFER_STD(0x1010, unknown_exception)
 
 	/* Watchdog Timer (WDT) Exception. (from 0x1020) */
 WDTException:
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S
index 9cc01948651f..e06cb1c84951 100644
--- a/arch/powerpc/kernel/head_44x.S
+++ b/arch/powerpc/kernel/head_44x.S
@@ -278,7 +278,7 @@ interrupt_base:
 	FP_UNAVAILABLE_EXCEPTION
 #else
 	EXCEPTION(0x2010, BOOKE_INTERRUPT_FP_UNAVAIL, \
-		  FloatingPointUnavailable, unknown_exception, EXC_XFER_EE)
+		  FloatingPointUnavailable, unknown_exception, EXC_XFER_STD)
 #endif
 	/* System Call Interrupt */
 	START_EXCEPTION(SystemCall)
@@ -287,7 +287,7 @@ interrupt_base:
 
 	/* Auxiliary Processor Unavailable Interrupt */
 	EXCEPTION(0x2020, BOOKE_INTERRUPT_AP_UNAVAIL, \
-		  AuxillaryProcessorUnavailable, unknown_exception, EXC_XFER_EE)
+		  AuxillaryProcessorUnavailable, unknown_exception, EXC_XFER_STD)
 
 	/* Decrementer Interrupt */
 	DECREMENTER_EXCEPTION
@@ -295,7 +295,7 @@ interrupt_base:
 	/* Fixed Internal Timer Interrupt */
 	/* TODO: Add FIT support */
 	EXCEPTION(0x1010, BOOKE_INTERRUPT_FIT, FixedIntervalTimer, \
-		  unknown_exception, EXC_XFER_EE)
+		  unknown_exception, EXC_XFER_STD)
 
 	/* Watchdog Timer Interrupt */
 	/* TODO: Add watchdog support */
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index dfd5a8195e5e..336b9921c0da 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -167,7 +167,7 @@ Alignment:
 	mfspr	r5,SPRN_DSISR
 	stw	r5,_DSISR(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_EE(0x600, alignment_exception)
+	EXC_XFER_STD(0x600, alignment_exception)
 
 /* Program check exception */
 	EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
@@ -179,8 +179,8 @@ Alignment:
 /* Decrementer */
 	EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE)
 
-	EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_STD)
 
 /* System call */
 	. = 0xc00
@@ -190,8 +190,8 @@ SystemCall:
 
 /* Single step - not used on 601 */
 	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
-	EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0xf00, Trap_0f, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0xf00, Trap_0f, unknown_exception, EXC_XFER_STD)
 
 /* On the MPC8xx, this is a software emulation interrupt.  It occurs
  * for all unimplemented and illegal instructions.
@@ -491,13 +491,13 @@ dtlbie:
 	/* 0x300 is DataAccess exception, needed by bad_page_fault() */
 	EXC_XFER_LITE(0x300, handle_page_fault)
 
-	EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1600, Trap_16, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1700, Trap_17, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1600, Trap_16, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1700, Trap_17, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_STD)
 
 /* On the MPC8xx, these next four traps are used for development
  * support of breakpoints and such.  Someday I will get around to
@@ -519,7 +519,7 @@ DataBreakpoint:
 	mfspr	r4,SPRN_BAR
 	stw	r4,_DAR(r11)
 	mfspr	r5,SPRN_DSISR
-	EXC_XFER_EE(0x1c00, do_break)
+	EXC_XFER_STD(0x1c00, do_break)
 11:
 	mtcr	r10
 	mfspr	r10, SPRN_SPRG_SCRATCH0
@@ -539,10 +539,10 @@ InstructionBreakpoint:
 	mfspr	r10, SPRN_SPRG_SCRATCH0
 	rfi
 #else
-	EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_STD)
 #endif
-	EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_EE)
-	EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_STD)
+	EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_STD)
 
 	. = 0x2000
 
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index 612f54ba1125..264976c43f34 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -255,14 +255,6 @@ END_BTB_FLUSH_SECTION
 	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, NOCOPY, transfer_to_handler, \
 			  ret_from_except)
 
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
 /* Check for a single step debug exception while in an exception
  * handler before state has been saved.  This is to catch the case
  * where an instruction that we are trying to single step causes
@@ -405,7 +397,7 @@ END_BTB_FLUSH_SECTION
 	mfspr   r4,SPRN_DEAR;           /* Grab the DEAR and save it */	      \
 	stw     r4,_DEAR(r11);						      \
 	addi    r3,r1,STACK_FRAME_OVERHEAD;				      \
-	EXC_XFER_EE(0x0600, alignment_exception)
+	EXC_XFER_STD(0x0600, alignment_exception)
 
 #define PROGRAM_EXCEPTION						      \
 	START_EXCEPTION(Program)					      \
@@ -430,7 +422,7 @@ END_BTB_FLUSH_SECTION
 	bl	load_up_fpu;		/* if from user, just load it up */   \
 	b	fast_exception_return;					      \
 1:	addi	r3,r1,STACK_FRAME_OVERHEAD;				      \
-	EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
+	EXC_XFER_STD(0x800, kernel_fp_unavailable_exception)
 
 #ifndef __ASSEMBLY__
 struct exception_regs {
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 89f36623993d..47fb63c9de4d 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -387,7 +387,7 @@ interrupt_base:
 	EXC_XFER_LITE(0x0300, handle_page_fault)
 1:
 	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_EE_LITE(0x0300, CacheLockingException)
+	EXC_XFER_LITE(0x0300, CacheLockingException)
 
 	/* Instruction Storage Interrupt */
 	INSTRUCTION_STORAGE_EXCEPTION
@@ -408,10 +408,10 @@ interrupt_base:
 #ifdef CONFIG_E200
 	/* E200 treats 'normal' floating point instructions as FP Unavail exception */
 	EXCEPTION(0x0800, FP_UNAVAIL, FloatingPointUnavailable, \
-		  program_check_exception, EXC_XFER_EE)
+		  program_check_exception, EXC_XFER_STD)
 #else
 	EXCEPTION(0x0800, FP_UNAVAIL, FloatingPointUnavailable, \
-		  unknown_exception, EXC_XFER_EE)
+		  unknown_exception, EXC_XFER_STD)
 #endif
 #endif
 
@@ -422,7 +422,7 @@ interrupt_base:
 
 	/* Auxiliary Processor Unavailable Interrupt */
 	EXCEPTION(0x2900, AP_UNAVAIL, AuxillaryProcessorUnavailable, \
-		  unknown_exception, EXC_XFER_EE)
+		  unknown_exception, EXC_XFER_STD)
 
 	/* Decrementer Interrupt */
 	DECREMENTER_EXCEPTION
@@ -430,7 +430,7 @@ interrupt_base:
 	/* Fixed Internal Timer Interrupt */
 	/* TODO: Add FIT support */
 	EXCEPTION(0x3100, FIT, FixedIntervalTimer, \
-		  unknown_exception, EXC_XFER_EE)
+		  unknown_exception, EXC_XFER_STD)
 
 	/* Watchdog Timer Interrupt */
 #ifdef CONFIG_BOOKE_WDT
@@ -640,25 +640,25 @@ END_BTB_FLUSH_SECTION
 	bl	load_up_spe
 	b	fast_exception_return
 1:	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_EE_LITE(0x2010, KernelSPE)
+	EXC_XFER_LITE(0x2010, KernelSPE)
 #elif defined(CONFIG_SPE_POSSIBLE)
 	EXCEPTION(0x2020, SPE_UNAVAIL, SPEUnavailable, \
-		  unknown_exception, EXC_XFER_EE)
+		  unknown_exception, EXC_XFER_STD)
 #endif /* CONFIG_SPE_POSSIBLE */
 
 	/* SPE Floating Point Data */
 #ifdef CONFIG_SPE
 	EXCEPTION(0x2030, SPE_FP_DATA, SPEFloatingPointData,
-		  SPEFloatingPointException, EXC_XFER_EE)
+		  SPEFloatingPointException, EXC_XFER_STD)
 
 	/* SPE Floating Point Round */
 	EXCEPTION(0x2050, SPE_FP_ROUND, SPEFloatingPointRound, \
-		  SPEFloatingPointRoundException, EXC_XFER_EE)
+		  SPEFloatingPointRoundException, EXC_XFER_STD)
 #elif defined(CONFIG_SPE_POSSIBLE)
 	EXCEPTION(0x2040, SPE_FP_DATA, SPEFloatingPointData,
-		  unknown_exception, EXC_XFER_EE)
+		  unknown_exception, EXC_XFER_STD)
 	EXCEPTION(0x2050, SPE_FP_ROUND, SPEFloatingPointRound, \
-		  unknown_exception, EXC_XFER_EE)
+		  unknown_exception, EXC_XFER_STD)
 #endif /* CONFIG_SPE_POSSIBLE */
 
 
@@ -681,10 +681,10 @@ END_BTB_FLUSH_SECTION
 			   unknown_exception)
 
 	/* Hypercall */
-	EXCEPTION(0, HV_SYSCALL, Hypercall, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0, HV_SYSCALL, Hypercall, unknown_exception, EXC_XFER_STD)
 
 	/* Embedded Hypervisor Privilege */
-	EXCEPTION(0, HV_PRIV, Ehvpriv, unknown_exception, EXC_XFER_EE)
+	EXCEPTION(0, HV_PRIV, Ehvpriv, unknown_exception, EXC_XFER_STD)
 
 interrupt_end:
 
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 12/16] powerpc/32: get rid of COPY_EE in exception entry
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (10 preceding siblings ...)
  2019-02-08 12:52 ` [RFC PATCH v1 11/16] powerpc/32: Enter exceptions with MSR_EE unset Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 13/16] powerpc: Fix 32-bit handling of MSR_EE on exceptions Christophe Leroy
                   ` (3 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

EXC_XFER_TEMPLATE() is not called with COPY_EE anymore so
we can get rid of copyee parameters and related COPY_EE and NOCOPY
macros.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[splited out from benh RFC patch]

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.h    | 12 ++++--------
 arch/powerpc/kernel/head_40x.S   |  8 +++-----
 arch/powerpc/kernel/head_booke.h | 22 ++++++++--------------
 3 files changed, 15 insertions(+), 27 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 8881b6887841..14cb0af2f494 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -103,28 +103,24 @@
 	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
 	xfer(n, hdlr)
 
-#define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret)	\
+#define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret)		\
 	li	r10,trap;					\
 	stw	r10,_TRAP(r11);					\
 	LOAD_MSR_KERNEL(r10, msr);				\
-	copyee(r10, r9);					\
 	bl	tfer;						\
 	.long	hdlr;						\
 	.long	ret
 
-#define COPY_EE(d, s)		rlwimi d,s,0,MSR_EE
-#define NOCOPY(d, s)
-
 #define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full,	\
+	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full,	\
 			  ret_from_except_full)
 
 #define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \
 			  ret_from_except)
 
 #define EXC_XFER_SYS(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, NOCOPY, transfer_to_handler, \
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, transfer_to_handler, \
 			  ret_from_except)
 
 #endif /* __HEAD_32_H__ */
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 549db4fed183..1afab9190147 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -166,8 +166,7 @@ _ENTRY(saved_ksp_limit)
 	CRITICAL_EXCEPTION_PROLOG;				\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
 	EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
-			  NOCOPY, crit_transfer_to_handler,	\
-			  ret_from_crit_exc)
+			  crit_transfer_to_handler, ret_from_crit_exc)
 
 /*
  * 0x0100 - Critical Interrupt Exception
@@ -651,7 +650,7 @@ _ENTRY(saved_ksp_limit)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	EXC_XFER_TEMPLATE(DebugException, 0x2002, \
 		(MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
-		NOCOPY, crit_transfer_to_handler, ret_from_crit_exc)
+		crit_transfer_to_handler, ret_from_crit_exc)
 
 	/* Programmable Interval Timer (PIT) Exception. (from 0x1000) */
 Decrementer:
@@ -673,8 +672,7 @@ WDTException:
 	addi	r3,r1,STACK_FRAME_OVERHEAD;
 	EXC_XFER_TEMPLATE(WatchdogException, 0x1020+2,
 	                  (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)),
-			  NOCOPY, crit_transfer_to_handler,
-			  ret_from_crit_exc)
+			  crit_transfer_to_handler, ret_from_crit_exc)
 
 /*
  * The other Data TLB exceptions bail out to this point
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index 264976c43f34..56dd1341eb3d 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -217,8 +217,7 @@ END_BTB_FLUSH_SECTION
 	CRITICAL_EXCEPTION_PROLOG(intno);				\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;				\
 	EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
-			  NOCOPY, crit_transfer_to_handler, \
-			  ret_from_crit_exc)
+			  crit_transfer_to_handler, ret_from_crit_exc)
 
 #define MCHECK_EXCEPTION(n, label, hdlr)			\
 	START_EXCEPTION(label);					\
@@ -227,32 +226,27 @@ END_BTB_FLUSH_SECTION
 	stw	r5,_ESR(r11);					\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
 	EXC_XFER_TEMPLATE(hdlr, n+4, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
-			  NOCOPY, mcheck_transfer_to_handler,   \
-			  ret_from_mcheck_exc)
+			  mcheck_transfer_to_handler, ret_from_mcheck_exc)
 
-#define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret)	\
+#define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret)	\
 	li	r10,trap;					\
 	stw	r10,_TRAP(r11);					\
 	lis	r10,msr@h;					\
 	ori	r10,r10,msr@l;					\
-	copyee(r10, r9);					\
 	bl	tfer;		 				\
 	.long	hdlr;						\
 	.long	ret
 
-#define COPY_EE(d, s)		rlwimi d,s,0,16,16
-#define NOCOPY(d, s)
-
 #define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full, \
+	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full, \
 			  ret_from_except_full)
 
 #define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \
 			  ret_from_except)
 
 #define EXC_XFER_SYS(n, hdlr)						\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, NOCOPY, transfer_to_handler, \
+	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, transfer_to_handler, \
 			  ret_from_except)
 
 /* Check for a single step debug exception while in an exception
@@ -319,7 +313,7 @@ END_BTB_FLUSH_SECTION
 	/* continue normal handling for a debug exception... */		      \
 2:	mfspr	r4,SPRN_DBSR;						      \
 	addi	r3,r1,STACK_FRAME_OVERHEAD;				      \
-	EXC_XFER_TEMPLATE(DebugException, 0x2008, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, debug_transfer_to_handler, ret_from_debug_exc)
+	EXC_XFER_TEMPLATE(DebugException, 0x2008, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), debug_transfer_to_handler, ret_from_debug_exc)
 
 #define DEBUG_CRIT_EXCEPTION						      \
 	START_EXCEPTION(DebugCrit);					      \
@@ -372,7 +366,7 @@ END_BTB_FLUSH_SECTION
 	/* continue normal handling for a critical exception... */	      \
 2:	mfspr	r4,SPRN_DBSR;						      \
 	addi	r3,r1,STACK_FRAME_OVERHEAD;				      \
-	EXC_XFER_TEMPLATE(DebugException, 0x2002, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, crit_transfer_to_handler, ret_from_crit_exc)
+	EXC_XFER_TEMPLATE(DebugException, 0x2002, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), crit_transfer_to_handler, ret_from_crit_exc)
 
 #define DATA_STORAGE_EXCEPTION						      \
 	START_EXCEPTION(DataStorage)					      \
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 13/16] powerpc: Fix 32-bit handling of MSR_EE on exceptions
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (11 preceding siblings ...)
  2019-02-08 12:52 ` [RFC PATCH v1 12/16] powerpc/32: get rid of COPY_EE in exception entry Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 14/16] powerpc/32: implement fast entry for syscalls on non BOOKE Christophe Leroy
                   ` (2 subsequent siblings)
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

[text mostly copied from benh's RFC/WIP]

ppc32 are still doing something rather gothic and wrong on 32-bit
which we stopped doing on 64-bit a while ago.

We have that thing where some handlers "copy" the EE value from the
original stack frame into the new MSR before transferring to the
handler.

Thus for a number of exceptions, we enter the handlers with interrupts
enabled.

This is rather fishy, some of the stuff that handlers might do early
on such as irq_enter/exit or user_exit, context tracking, etc...
should be run with interrupts off afaik.

Generally our handlers know when to re-enable interrupts if needed.

The problem we were having is that we assumed these interrupts would
return with interrupts enabled. However that isn't the case.

Instead, this patch changes things so that we always enter exception
handlers with interrupts *off* with the notable exception of syscalls
which are special (and get a fast path).

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/entry_32.S | 117 ++++++++++++++++++++++++-----------------
 1 file changed, 68 insertions(+), 49 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index b489aebdc5c5..1e11528d45ae 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -36,6 +36,7 @@
 #include <asm/asm-405.h>
 #include <asm/feature-fixups.h>
 #include <asm/barrier.h>
+#include <asm/bug.h>
 
 #include "head_32.h"
 
@@ -200,19 +201,42 @@ transfer_to_handler_cont:
 	mtspr	SPRN_NRI, r0
 #endif
 #ifdef CONFIG_TRACE_IRQFLAGS
+	/*
+	 * When tracing IRQ state (lockdep) we enable the MMU before we call
+	 * the IRQ tracing functions as they might access vmalloc space or
+	 * perform IOs for console output.
+	 *
+	 * To speed up the syscall path where interrupts stay on, let's check
+	 * first if we are changing the MSR value at all.
+	 */
+	tophys(r12, r1)
+	lwz	r12,_MSR(r12)
+	xor	r12,r10,r12
+	andi.	r12,r12,MSR_EE
+	bne	1f
+
+	/* MSR isn't changing, just transition directly */
+#endif
+	mtspr	SPRN_SRR0,r11
+	mtspr	SPRN_SRR1,r10
+	mtlr	r9
+	SYNC
+	RFI				/* jump to handler, enable MMU */
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+1:	/* MSR is changing, re-enable MMU so we can notify lockdep. We need to
+	 * keep interrupts disabled at this point otherwise we might risk
+	 * taking an interrupt before we tell lockdep they are enabled.
+	 */
 	lis	r12,reenable_mmu@h
 	ori	r12,r12,reenable_mmu@l
+	LOAD_MSR_KERNEL(r0, MSR_KERNEL)
 	mtspr	SPRN_SRR0,r12
-	mtspr	SPRN_SRR1,r10
+	mtspr	SPRN_SRR1,r0
 	SYNC
 	RFI
-reenable_mmu:				/* re-enable mmu so we can */
-	mfmsr	r10
-	lwz	r12,_MSR(r1)
-	xor	r10,r10,r12
-	andi.	r10,r10,MSR_EE		/* Did EE change? */
-	beq	1f
 
+reenable_mmu:
 	/*
 	 * The trace_hardirqs_off will use CALLER_ADDR0 and CALLER_ADDR1.
 	 * If from user mode there is only one stack frame on the stack, and
@@ -227,14 +251,24 @@ reenable_mmu:				/* re-enable mmu so we can */
 	 * they aren't useful past this point (aren't syscall arguments),
 	 * the rest is restored from the exception frame.
 	 */
+
+	/* Are we enabling or disabling interrupts ? */
+	andi.	r0,r10,MSR_EE
+
 	stwu	r1,-32(r1)
 	stw	r9,8(r1)
 	stw	r11,12(r1)
 	stw	r3,16(r1)
 	stw	r4,20(r1)
 	stw	r5,24(r1)
-	bl	trace_hardirqs_off
-	lwz	r5,24(r1)
+
+	bne-	0f
+
+	/* If we are disabling interrupts (normal case), simply log it with
+	 * lockdep
+	 */
+1:	bl	trace_hardirqs_off
+2:	lwz	r5,24(r1)
 	lwz	r4,20(r1)
 	lwz	r3,16(r1)
 	lwz	r11,12(r1)
@@ -244,15 +278,22 @@ reenable_mmu:				/* re-enable mmu so we can */
 	lwz	r6,GPR6(r1)
 	lwz	r7,GPR7(r1)
 	lwz	r8,GPR8(r1)
-1:	mtctr	r11
+	mtctr	r11
 	mtlr	r9
 	bctr				/* jump to handler */
-#else /* CONFIG_TRACE_IRQFLAGS */
-	mtspr	SPRN_SRR0,r11
-	mtspr	SPRN_SRR1,r10
-	mtlr	r9
-	SYNC
-	RFI				/* jump to handler, enable MMU */
+
+	/* If we are enabling interrupt, this is a syscall. They shouldn't
+	 * happen while interrupts are disabled, so let's do a warning here.
+	 */
+0:	trap
+	EMIT_BUG_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING
+	bl	trace_hardirqs_on
+
+	/* Now enable for real */
+	mfmsr	r10
+	ori	r10,r10,MSR_EE
+	mtmsr	r10
+	b	2b
 #endif /* CONFIG_TRACE_IRQFLAGS */
 
 #if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
@@ -308,30 +349,15 @@ _GLOBAL(DoSyscall)
 	lwz	r11,_CCR(r1)	/* Clear SO bit in CR */
 	rlwinm	r11,r11,0,4,2
 	stw	r11,_CCR(r1)
+
 #ifdef CONFIG_TRACE_IRQFLAGS
-	/* Return from syscalls can (and generally will) hard enable
-	 * interrupts. You aren't supposed to call a syscall with
-	 * interrupts disabled in the first place. However, to ensure
-	 * that we get it right vs. lockdep if it happens, we force
-	 * that hard enable here with appropriate tracing if we see
-	 * that we have been called with interrupts off
-	 */
+	/* Make sure interrupts are enabled */
 	mfmsr	r11
 	andi.	r12,r11,MSR_EE
-	bne+	1f
-	/* We came in with interrupts disabled, we enable them now */
-	bl	trace_hardirqs_on
-	mfmsr	r11
-	lwz	r0,GPR0(r1)
-	lwz	r3,GPR3(r1)
-	lwz	r4,GPR4(r1)
-	ori	r11,r11,MSR_EE
-	lwz	r5,GPR5(r1)
-	lwz	r6,GPR6(r1)
-	lwz	r7,GPR7(r1)
-	lwz	r8,GPR8(r1)
-	mtmsr	r11
-1:
+	/* We came in with interrupts disabled, we WARN and mark them enabled
+	 * for lockdep now */
+0:	tweqi	r12, 0
+	EMIT_BUG_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING
 #endif /* CONFIG_TRACE_IRQFLAGS */
 	lwz	r11,TI_FLAGS(r2)
 	andi.	r11,r11,_TIF_SYSCALL_DOTRACE
@@ -385,8 +411,7 @@ syscall_exit_cont:
 	lwz	r8,_MSR(r1)
 #ifdef CONFIG_TRACE_IRQFLAGS
 	/* If we are going to return from the syscall with interrupts
-	 * off, we trace that here. It shouldn't happen though but we
-	 * want to catch the bugger if it does right ?
+	 * off, we trace that here. It shouldn't normally happen.
 	 */
 	andi.	r10,r8,MSR_EE
 	bne+	1f
@@ -903,13 +928,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_47x)
 	 * off in this assembly code while peeking at TI_FLAGS() and such. However
 	 * we need to inform it if the exception turned interrupts off, and we
 	 * are about to trun them back on.
-	 *
-	 * The problem here sadly is that we don't know whether the exceptions was
-	 * one that turned interrupts off or not. So we always tell lockdep about
-	 * turning them on here when we go back to wherever we came from with EE
-	 * on, even if that may meen some redudant calls being tracked. Maybe later
-	 * we could encode what the exception did somewhere or test the exception
-	 * type in the pt_regs but that sounds overkill
 	 */
 	andi.	r10,r9,MSR_EE
 	beq	1f
@@ -1194,9 +1212,10 @@ do_work:			/* r10 contains MSR_KERNEL here */
 	beq	do_user_signal
 
 do_resched:			/* r10 contains MSR_KERNEL here */
-	/* Note: We don't need to inform lockdep that we are enabling
-	 * interrupts here. As far as it knows, they are already enabled
-	 */
+#ifdef CONFIG_TRACE_IRQFLAGS
+	bl	trace_hardirqs_on
+	mfmsr	r10
+#endif
 	ori	r10,r10,MSR_EE
 	SYNC
 	MTMSRD(r10)		/* hard-enable interrupts */
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 14/16] powerpc/32: implement fast entry for syscalls on non BOOKE
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (12 preceding siblings ...)
  2019-02-08 12:52 ` [RFC PATCH v1 13/16] powerpc: Fix 32-bit handling of MSR_EE on exceptions Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-10 18:05   ` christophe leroy
  2019-02-08 12:52 ` [RFC PATCH v1 15/16] powerpc/32: Remove MSR_PR test when returning from syscall Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 16/16] powerpc/32: don't do syscall stuff in transfer_to_handler on non BOOKE Christophe Leroy
  15 siblings, 1 reply; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

This patch implements a fast entry for syscalls.

Syscalls don't have to preserve non volatile registers except LR.

This patch then implement a fast entry for syscalls, where
volatile registers get clobbered.

As this entry is dedicated to syscall it always sets MSR_EE
and warns in case MSR_EE was previously off

It also assumes that the call is always from user, system calls are
unexpected from kernel.

The overall series improves null_syscall selftest by 12,5% on an 83xx
and by 17% on a 8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/entry_32.S | 42 +++++++++++++++++++++
 arch/powerpc/kernel/head_32.S  |  3 +-
 arch/powerpc/kernel/head_32.h  | 85 ++++++++++++++++++++++++++++++++++++++++--
 arch/powerpc/kernel/head_40x.S |  3 +-
 arch/powerpc/kernel/head_8xx.S |  3 +-
 5 files changed, 126 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 1e11528d45ae..137bd2103051 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -335,6 +335,46 @@ stack_ovf:
 	SYNC
 	RFI
 
+#ifndef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
+#ifdef CONFIG_TRACE_IRQFLAGS
+trace_syscall_entry_irq_off:
+	/*
+	 * The trace_hardirqs_off will use CALLER_ADDR0 and CALLER_ADDR1.
+	 * If from user mode there is only one stack frame on the stack, and
+	 * accessing CALLER_ADDR1 will cause oops. So we need create a dummy
+	 * stack frame to make trace_hardirqs_on happy.
+	 *
+	 */
+	stwu	r1,-32(r1)
+
+	/*
+	 * Syscall shouldn't happen while interrupts are disabled,
+	 * so let's do a warning here.
+	 */
+0:	trap
+	EMIT_BUG_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING
+	bl	trace_hardirqs_on
+
+	addi	r1,r1,32
+
+	/* Now enable for real */
+	LOAD_MSR_KERNEL(r10, MSR_KERNEL | MSR_EE)
+	mtmsr	r10
+
+	REST_GPR(0, r1)
+	REST_4GPRS(3, r1)
+	REST_2GPRS(7, r1)
+	b	DoSyscall
+#endif /* CONFIG_TRACE_IRQFLAGS */
+
+	.globl	transfer_to_syscall
+transfer_to_syscall:
+#ifdef CONFIG_TRACE_IRQFLAGS
+	andi.	r12,r9,MSR_EE
+	beq-	trace_syscall_entry_irq_off
+#endif /* CONFIG_TRACE_IRQFLAGS */
+#endif /* !CONFIG_BOOKE */
+
 /*
  * Handle a system call.
  */
@@ -346,9 +386,11 @@ _GLOBAL(DoSyscall)
 	stw	r3,ORIG_GPR3(r1)
 	li	r12,0
 	stw	r12,RESULT(r1)
+#ifdef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
 	lwz	r11,_CCR(r1)	/* Clear SO bit in CR */
 	rlwinm	r11,r11,0,4,2
 	stw	r11,_CCR(r1)
+#endif
 
 #ifdef CONFIG_TRACE_IRQFLAGS
 	/* Make sure interrupts are enabled */
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 3a1df9edf6da..7576e1374a69 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -368,8 +368,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
 	. = 0xc00
 	DO_KVM  0xc00
 SystemCall:
-	EXCEPTION_PROLOG
-	EXC_XFER_SYS(0xc00, DoSyscall)
+	SYSCALL_ENTRY	0xc00
 
 /* Single step - not used on 601 */
 	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 14cb0af2f494..4a692553651f 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -73,6 +73,87 @@
 	SAVE_2GPRS(7, r11)
 .endm
 
+.macro SYSCALL_ENTRY trapno
+	mfspr	r12,SPRN_SPRG_THREAD
+	mfcr	r10
+	lwz	r11,TASK_STACK-THREAD(r12)
+	mflr	r9
+	addi	r11,r11,THREAD_SIZE - INT_FRAME_SIZE
+	rlwinm	r10,r10,0,4,2	/* Clear SO bit in CR */
+	tophys(r11,r11)
+	stw	r10,_CCR(r11)		/* save registers */
+	mfspr	r10,SPRN_SRR0
+	stw	r9,_LINK(r11)
+	mfspr	r9,SPRN_SRR1
+	stw	r1,GPR1(r11)
+	stw	r1,0(r11)
+	tovirt(r1,r11)			/* set new kernel sp */
+	stw	r10,_NIP(r11)
+#ifdef CONFIG_40x
+	rlwinm	r9,r9,0,14,12		/* clear MSR_WE (necessary?) */
+#else
+	LOAD_MSR_KERNEL(r10, MSR_KERNEL & ~(MSR_IR|MSR_DR)) /* can take exceptions */
+	MTMSRD(r10)			/* (except for mach check in rtas) */
+#endif
+	lis	r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
+	stw	r2,GPR2(r11)
+	addi	r10,r10,STACK_FRAME_REGS_MARKER@l
+	stw	r9,_MSR(r11)
+	li	r2, \trapno + 1
+	stw	r10,8(r11)
+	stw	r2,_TRAP(r11)
+	SAVE_GPR(0, r11)
+	SAVE_4GPRS(3, r11)
+	SAVE_2GPRS(7, r11)
+	addi	r11,r1,STACK_FRAME_OVERHEAD
+	addi	r2,r12,-THREAD
+	stw	r11,PT_REGS(r12)
+#if defined(CONFIG_40x)
+	/* Check to see if the dbcr0 register is set up to debug.  Use the
+	   internal debug mode bit to do this. */
+	lwz	r12,THREAD_DBCR0(r12)
+	andis.	r12,r12,DBCR0_IDM@h
+#endif
+	ACCOUNT_CPU_USER_ENTRY(r2, r11, r12)
+#if defined(CONFIG_40x)
+	beq+	3f
+	/* From user and task is ptraced - load up global dbcr0 */
+	li	r12,-1			/* clear all pending debug events */
+	mtspr	SPRN_DBSR,r12
+	lis	r11,global_dbcr0@ha
+	tophys(r11,r11)
+	addi	r11,r11,global_dbcr0@l
+	lwz	r12,0(r11)
+	mtspr	SPRN_DBCR0,r12
+	lwz	r12,4(r11)
+	addi	r12,r12,-1
+	stw	r12,4(r11)
+#endif
+
+3:
+	tovirt(r2, r2)			/* set r2 to current */
+	lis	r11, transfer_to_syscall@h
+	ori	r11, r11, transfer_to_syscall@l
+#ifdef CONFIG_TRACE_IRQFLAGS
+	/*
+	 * If MSR is changing we need to keep interrupts disabled at this point
+	 * otherwise we might risk taking an interrupt before we tell lockdep
+	 * they are enabled.
+	 */
+	LOAD_MSR_KERNEL(r10, MSR_KERNEL)
+	rlwimi	r10, r9, 0, MSR_EE
+#else
+	LOAD_MSR_KERNEL(r10, MSR_KERNEL | MSR_EE)
+#endif
+#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS)
+	mtspr	SPRN_NRI, r0
+#endif
+	mtspr	SPRN_SRR1,r10
+	mtspr	SPRN_SRR0,r11
+	SYNC
+	RFI				/* jump to handler, enable MMU */
+.endm
+
 /*
  * Note: code which follows this uses cr0.eq (set if from kernel),
  * r11, r12 (SRR0), and r9 (SRR1).
@@ -119,8 +200,4 @@
 	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \
 			  ret_from_except)
 
-#define EXC_XFER_SYS(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, transfer_to_handler, \
-			  ret_from_except)
-
 #endif /* __HEAD_32_H__ */
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 1afab9190147..f5704488c4fc 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -348,8 +348,7 @@ _ENTRY(saved_ksp_limit)
 
 /* 0x0C00 - System Call Exception */
 	START_EXCEPTION(0x0C00,	SystemCall)
-	EXCEPTION_PROLOG
-	EXC_XFER_SYS(0xc00, DoSyscall)
+	SYSCALL_ENTRY	0xc00
 
 	EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_STD)
 	EXCEPTION(0x0E00, Trap_0E, unknown_exception, EXC_XFER_STD)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 336b9921c0da..362b2150a3a0 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -185,8 +185,7 @@ Alignment:
 /* System call */
 	. = 0xc00
 SystemCall:
-	EXCEPTION_PROLOG
-	EXC_XFER_SYS(0xc00, DoSyscall)
+	SYSCALL_ENTRY	0xc00
 
 /* Single step - not used on 601 */
 	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 15/16] powerpc/32: Remove MSR_PR test when returning from syscall
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (13 preceding siblings ...)
  2019-02-08 12:52 ` [RFC PATCH v1 14/16] powerpc/32: implement fast entry for syscalls on non BOOKE Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  2019-02-08 12:52 ` [RFC PATCH v1 16/16] powerpc/32: don't do syscall stuff in transfer_to_handler on non BOOKE Christophe Leroy
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

syscalls are from user only, so we can account time without checking
whether returning to kernel or user as it will only be user.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/entry_32.S | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 137bd2103051..0927d5ff1e79 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -482,12 +482,7 @@ BEGIN_FTR_SECTION
 	lwarx	r7,0,r1
 END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 	stwcx.	r0,0,r1			/* to clear the reservation */
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-	andi.	r4,r8,MSR_PR
-	beq	3f
 	ACCOUNT_CPU_USER_EXIT(r2, r5, r7)
-3:
-#endif
 	lwz	r4,_LINK(r1)
 	lwz	r5,_CCR(r1)
 	mtlr	r4
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [RFC PATCH v1 16/16] powerpc/32: don't do syscall stuff in transfer_to_handler on non BOOKE
  2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
                   ` (14 preceding siblings ...)
  2019-02-08 12:52 ` [RFC PATCH v1 15/16] powerpc/32: Remove MSR_PR test when returning from syscall Christophe Leroy
@ 2019-02-08 12:52 ` Christophe Leroy
  15 siblings, 0 replies; 21+ messages in thread
From: Christophe Leroy @ 2019-02-08 12:52 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

As syscalls are now handled via a fast entry path, syscall related
actions can be removed from the generic transfer_to_handler path.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/entry_32.S | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 0927d5ff1e79..85f1fc88c237 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -211,7 +211,9 @@ transfer_to_handler_cont:
 	 */
 	tophys(r12, r1)
 	lwz	r12,_MSR(r12)
+#ifdef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
 	xor	r12,r10,r12
+#endif
 	andi.	r12,r12,MSR_EE
 	bne	1f
 
@@ -252,8 +254,10 @@ reenable_mmu:
 	 * the rest is restored from the exception frame.
 	 */
 
+#ifdef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
 	/* Are we enabling or disabling interrupts ? */
 	andi.	r0,r10,MSR_EE
+#endif
 
 	stwu	r1,-32(r1)
 	stw	r9,8(r1)
@@ -262,7 +266,9 @@ reenable_mmu:
 	stw	r4,20(r1)
 	stw	r5,24(r1)
 
+#ifdef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
 	bne-	0f
+#endif
 
 	/* If we are disabling interrupts (normal case), simply log it with
 	 * lockdep
@@ -282,6 +288,7 @@ reenable_mmu:
 	mtlr	r9
 	bctr				/* jump to handler */
 
+#ifdef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
 	/* If we are enabling interrupt, this is a syscall. They shouldn't
 	 * happen while interrupts are disabled, so let's do a warning here.
 	 */
@@ -294,6 +301,7 @@ reenable_mmu:
 	ori	r10,r10,MSR_EE
 	mtmsr	r10
 	b	2b
+#endif
 #endif /* CONFIG_TRACE_IRQFLAGS */
 
 #if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)
-- 
2.13.3


^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [RFC PATCH v1 14/16] powerpc/32: implement fast entry for syscalls on non BOOKE
  2019-02-08 12:52 ` [RFC PATCH v1 14/16] powerpc/32: implement fast entry for syscalls on non BOOKE Christophe Leroy
@ 2019-02-10 18:05   ` christophe leroy
  0 siblings, 0 replies; 21+ messages in thread
From: christophe leroy @ 2019-02-10 18:05 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel



Le 08/02/2019 à 13:52, Christophe Leroy a écrit :
> This patch implements a fast entry for syscalls.
> 
> Syscalls don't have to preserve non volatile registers except LR.
> 
> This patch then implement a fast entry for syscalls, where
> volatile registers get clobbered.
> 
> As this entry is dedicated to syscall it always sets MSR_EE
> and warns in case MSR_EE was previously off
> 
> It also assumes that the call is always from user, system calls are
> unexpected from kernel.
> 
> The overall series improves null_syscall selftest by 12,5% on an 83xx
> and by 17% on a 8xx.
> 
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

The following addition is required to avoid build failure on 40x as 
global_dbcr0 is going to be accessed from head_40x.S

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 85f1fc88c237..987f0fafc999 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -1247,6 +1247,7 @@ load_dbcr0:

  	.section .bss
  	.align	4
+	.global global_dbcr0
  global_dbcr0:
  	.space	8*NR_CPUS
  	.previous

Christophe

> ---
>   arch/powerpc/kernel/entry_32.S | 42 +++++++++++++++++++++
>   arch/powerpc/kernel/head_32.S  |  3 +-
>   arch/powerpc/kernel/head_32.h  | 85 ++++++++++++++++++++++++++++++++++++++++--
>   arch/powerpc/kernel/head_40x.S |  3 +-
>   arch/powerpc/kernel/head_8xx.S |  3 +-
>   5 files changed, 126 insertions(+), 10 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index 1e11528d45ae..137bd2103051 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -335,6 +335,46 @@ stack_ovf:
>   	SYNC
>   	RFI
>   
> +#ifndef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
> +#ifdef CONFIG_TRACE_IRQFLAGS
> +trace_syscall_entry_irq_off:
> +	/*
> +	 * The trace_hardirqs_off will use CALLER_ADDR0 and CALLER_ADDR1.
> +	 * If from user mode there is only one stack frame on the stack, and
> +	 * accessing CALLER_ADDR1 will cause oops. So we need create a dummy
> +	 * stack frame to make trace_hardirqs_on happy.
> +	 *
> +	 */
> +	stwu	r1,-32(r1)
> +
> +	/*
> +	 * Syscall shouldn't happen while interrupts are disabled,
> +	 * so let's do a warning here.
> +	 */
> +0:	trap
> +	EMIT_BUG_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING
> +	bl	trace_hardirqs_on
> +
> +	addi	r1,r1,32
> +
> +	/* Now enable for real */
> +	LOAD_MSR_KERNEL(r10, MSR_KERNEL | MSR_EE)
> +	mtmsr	r10
> +
> +	REST_GPR(0, r1)
> +	REST_4GPRS(3, r1)
> +	REST_2GPRS(7, r1)
> +	b	DoSyscall
> +#endif /* CONFIG_TRACE_IRQFLAGS */
> +
> +	.globl	transfer_to_syscall
> +transfer_to_syscall:
> +#ifdef CONFIG_TRACE_IRQFLAGS
> +	andi.	r12,r9,MSR_EE
> +	beq-	trace_syscall_entry_irq_off
> +#endif /* CONFIG_TRACE_IRQFLAGS */
> +#endif /* !CONFIG_BOOKE */
> +
>   /*
>    * Handle a system call.
>    */
> @@ -346,9 +386,11 @@ _GLOBAL(DoSyscall)
>   	stw	r3,ORIG_GPR3(r1)
>   	li	r12,0
>   	stw	r12,RESULT(r1)
> +#ifdef CONFIG_BOOKE	/* to be removed once BOOKE uses fast syscall entry */
>   	lwz	r11,_CCR(r1)	/* Clear SO bit in CR */
>   	rlwinm	r11,r11,0,4,2
>   	stw	r11,_CCR(r1)
> +#endif
>   
>   #ifdef CONFIG_TRACE_IRQFLAGS
>   	/* Make sure interrupts are enabled */
> diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
> index 3a1df9edf6da..7576e1374a69 100644
> --- a/arch/powerpc/kernel/head_32.S
> +++ b/arch/powerpc/kernel/head_32.S
> @@ -368,8 +368,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
>   	. = 0xc00
>   	DO_KVM  0xc00
>   SystemCall:
> -	EXCEPTION_PROLOG
> -	EXC_XFER_SYS(0xc00, DoSyscall)
> +	SYSCALL_ENTRY	0xc00
>   
>   /* Single step - not used on 601 */
>   	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
> diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
> index 14cb0af2f494..4a692553651f 100644
> --- a/arch/powerpc/kernel/head_32.h
> +++ b/arch/powerpc/kernel/head_32.h
> @@ -73,6 +73,87 @@
>   	SAVE_2GPRS(7, r11)
>   .endm
>   
> +.macro SYSCALL_ENTRY trapno
> +	mfspr	r12,SPRN_SPRG_THREAD
> +	mfcr	r10
> +	lwz	r11,TASK_STACK-THREAD(r12)
> +	mflr	r9
> +	addi	r11,r11,THREAD_SIZE - INT_FRAME_SIZE
> +	rlwinm	r10,r10,0,4,2	/* Clear SO bit in CR */
> +	tophys(r11,r11)
> +	stw	r10,_CCR(r11)		/* save registers */
> +	mfspr	r10,SPRN_SRR0
> +	stw	r9,_LINK(r11)
> +	mfspr	r9,SPRN_SRR1
> +	stw	r1,GPR1(r11)
> +	stw	r1,0(r11)
> +	tovirt(r1,r11)			/* set new kernel sp */
> +	stw	r10,_NIP(r11)
> +#ifdef CONFIG_40x
> +	rlwinm	r9,r9,0,14,12		/* clear MSR_WE (necessary?) */
> +#else
> +	LOAD_MSR_KERNEL(r10, MSR_KERNEL & ~(MSR_IR|MSR_DR)) /* can take exceptions */
> +	MTMSRD(r10)			/* (except for mach check in rtas) */
> +#endif
> +	lis	r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
> +	stw	r2,GPR2(r11)
> +	addi	r10,r10,STACK_FRAME_REGS_MARKER@l
> +	stw	r9,_MSR(r11)
> +	li	r2, \trapno + 1
> +	stw	r10,8(r11)
> +	stw	r2,_TRAP(r11)
> +	SAVE_GPR(0, r11)
> +	SAVE_4GPRS(3, r11)
> +	SAVE_2GPRS(7, r11)
> +	addi	r11,r1,STACK_FRAME_OVERHEAD
> +	addi	r2,r12,-THREAD
> +	stw	r11,PT_REGS(r12)
> +#if defined(CONFIG_40x)
> +	/* Check to see if the dbcr0 register is set up to debug.  Use the
> +	   internal debug mode bit to do this. */
> +	lwz	r12,THREAD_DBCR0(r12)
> +	andis.	r12,r12,DBCR0_IDM@h
> +#endif
> +	ACCOUNT_CPU_USER_ENTRY(r2, r11, r12)
> +#if defined(CONFIG_40x)
> +	beq+	3f
> +	/* From user and task is ptraced - load up global dbcr0 */
> +	li	r12,-1			/* clear all pending debug events */
> +	mtspr	SPRN_DBSR,r12
> +	lis	r11,global_dbcr0@ha
> +	tophys(r11,r11)
> +	addi	r11,r11,global_dbcr0@l
> +	lwz	r12,0(r11)
> +	mtspr	SPRN_DBCR0,r12
> +	lwz	r12,4(r11)
> +	addi	r12,r12,-1
> +	stw	r12,4(r11)
> +#endif
> +
> +3:
> +	tovirt(r2, r2)			/* set r2 to current */
> +	lis	r11, transfer_to_syscall@h
> +	ori	r11, r11, transfer_to_syscall@l
> +#ifdef CONFIG_TRACE_IRQFLAGS
> +	/*
> +	 * If MSR is changing we need to keep interrupts disabled at this point
> +	 * otherwise we might risk taking an interrupt before we tell lockdep
> +	 * they are enabled.
> +	 */
> +	LOAD_MSR_KERNEL(r10, MSR_KERNEL)
> +	rlwimi	r10, r9, 0, MSR_EE
> +#else
> +	LOAD_MSR_KERNEL(r10, MSR_KERNEL | MSR_EE)
> +#endif
> +#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS)
> +	mtspr	SPRN_NRI, r0
> +#endif
> +	mtspr	SPRN_SRR1,r10
> +	mtspr	SPRN_SRR0,r11
> +	SYNC
> +	RFI				/* jump to handler, enable MMU */
> +.endm
> +
>   /*
>    * Note: code which follows this uses cr0.eq (set if from kernel),
>    * r11, r12 (SRR0), and r9 (SRR1).
> @@ -119,8 +200,4 @@
>   	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \
>   			  ret_from_except)
>   
> -#define EXC_XFER_SYS(n, hdlr)		\
> -	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL | MSR_EE, transfer_to_handler, \
> -			  ret_from_except)
> -
>   #endif /* __HEAD_32_H__ */
> diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
> index 1afab9190147..f5704488c4fc 100644
> --- a/arch/powerpc/kernel/head_40x.S
> +++ b/arch/powerpc/kernel/head_40x.S
> @@ -348,8 +348,7 @@ _ENTRY(saved_ksp_limit)
>   
>   /* 0x0C00 - System Call Exception */
>   	START_EXCEPTION(0x0C00,	SystemCall)
> -	EXCEPTION_PROLOG
> -	EXC_XFER_SYS(0xc00, DoSyscall)
> +	SYSCALL_ENTRY	0xc00
>   
>   	EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_STD)
>   	EXCEPTION(0x0E00, Trap_0E, unknown_exception, EXC_XFER_STD)
> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
> index 336b9921c0da..362b2150a3a0 100644
> --- a/arch/powerpc/kernel/head_8xx.S
> +++ b/arch/powerpc/kernel/head_8xx.S
> @@ -185,8 +185,7 @@ Alignment:
>   /* System call */
>   	. = 0xc00
>   SystemCall:
> -	EXCEPTION_PROLOG
> -	EXC_XFER_SYS(0xc00, DoSyscall)
> +	SYSCALL_ENTRY	0xc00
>   
>   /* Single step - not used on 601 */
>   	EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
> 

---
L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.
https://www.avast.com/antivirus


^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it
  2019-02-08 12:52 ` [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it Christophe Leroy
@ 2019-02-11  0:21   ` Benjamin Herrenschmidt
  2019-02-11  6:26     ` Christophe Leroy
  0 siblings, 1 reply; 21+ messages in thread
From: Benjamin Herrenschmidt @ 2019-02-11  0:21 UTC (permalink / raw)
  To: Christophe Leroy, Paul Mackerras, Michael Ellerman, Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

On Fri, 2019-02-08 at 12:52 +0000, Christophe Leroy wrote:
>  /*
> + * MSR_KERNEL is > 0x8000 on 4xx/Book-E since it include MSR_CE.
> + */
> +.macro __LOAD_MSR_KERNEL r, x
> +.if \x >= 0x8000
> +       lis \r, (\x)@h
> +       ori \r, \r, (\x)@l
> +.else
> +       li \r, (\x)
> +.endif
> +.endm
> +#define LOAD_MSR_KERNEL(r, x) __LOAD_MSR_KERNEL r, x
> +

You changed the limit from >= 0x10000 to >= 0x8000 without a
corresponding explanation as to why...

Ben.


^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it
  2019-02-11  0:21   ` Benjamin Herrenschmidt
@ 2019-02-11  6:26     ` Christophe Leroy
  2019-02-11  8:06       ` Benjamin Herrenschmidt
  0 siblings, 1 reply; 21+ messages in thread
From: Christophe Leroy @ 2019-02-11  6:26 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
	Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel



Le 11/02/2019 à 01:21, Benjamin Herrenschmidt a écrit :
> On Fri, 2019-02-08 at 12:52 +0000, Christophe Leroy wrote:
>>   /*
>> + * MSR_KERNEL is > 0x8000 on 4xx/Book-E since it include MSR_CE.
>> + */
>> +.macro __LOAD_MSR_KERNEL r, x
>> +.if \x >= 0x8000
>> +       lis \r, (\x)@h
>> +       ori \r, \r, (\x)@l
>> +.else
>> +       li \r, (\x)
>> +.endif
>> +.endm
>> +#define LOAD_MSR_KERNEL(r, x) __LOAD_MSR_KERNEL r, x
>> +
> 
> You changed the limit from >= 0x10000 to >= 0x8000 without a
> corresponding explanation as to why...

Yes, the existing LOAD_MSR_KERNEL() was buggy because 'li' takes a 
signed u16, ie between -0x8000 and 0x7999.

By chance it was working because until now nobody was trying to set 
MSR_KERNEL | MSR_EE.

Christophe

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it
  2019-02-11  6:26     ` Christophe Leroy
@ 2019-02-11  8:06       ` Benjamin Herrenschmidt
  0 siblings, 0 replies; 21+ messages in thread
From: Benjamin Herrenschmidt @ 2019-02-11  8:06 UTC (permalink / raw)
  To: Christophe Leroy, Paul Mackerras, Michael Ellerman, Nicholas Piggin
  Cc: linuxppc-dev, linux-kernel

On Mon, 2019-02-11 at 07:26 +0100, Christophe Leroy wrote:
> 
> Le 11/02/2019 à 01:21, Benjamin Herrenschmidt a écrit :
> > On Fri, 2019-02-08 at 12:52 +0000, Christophe Leroy wrote:
> > >   /*
> > > + * MSR_KERNEL is > 0x8000 on 4xx/Book-E since it include MSR_CE.
> > > + */
> > > +.macro __LOAD_MSR_KERNEL r, x
> > > +.if \x >= 0x8000
> > > +       lis \r, (\x)@h
> > > +       ori \r, \r, (\x)@l
> > > +.else
> > > +       li \r, (\x)
> > > +.endif
> > > +.endm
> > > +#define LOAD_MSR_KERNEL(r, x) __LOAD_MSR_KERNEL r, x
> > > +
> > 
> > You changed the limit from >= 0x10000 to >= 0x8000 without a
> > corresponding explanation as to why...
> 
> Yes, the existing LOAD_MSR_KERNEL() was buggy because 'li' takes a 
> signed u16, ie between -0x8000 and 0x7999.

Ah yes, I was only looking at the "large" case which is fine...

> By chance it was working because until now nobody was trying to set 
> MSR_KERNEL | MSR_EE.
> 
> Christophe


^ permalink raw reply	[flat|nested] 21+ messages in thread

end of thread, back to index

Thread overview: 21+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-02-08 12:52 [RFC PATCH v1 00/16] powerpc/32: Implement fast syscall entry Christophe Leroy
2019-02-08 12:52 ` [PATCH v1 01/16] powerpc: CONFIG_THREAD_INFO_IN_TASK series Christophe Leroy
2019-02-08 12:52 ` [PATCH v1 02/16] powerpc/32: Refactor EXCEPTION entry macros for head_8xx.S and head_32.S Christophe Leroy
2019-02-08 12:52 ` [PATCH v1 03/16] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it Christophe Leroy
2019-02-11  0:21   ` Benjamin Herrenschmidt
2019-02-11  6:26     ` Christophe Leroy
2019-02-11  8:06       ` Benjamin Herrenschmidt
2019-02-08 12:52 ` [PATCH v1 04/16] powerpc/32: make the 6xx/8xx EXC_XFER_TEMPLATE() similar to the 40x/booke one Christophe Leroy
2019-02-08 12:52 ` [PATCH v1 05/16] powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG Christophe Leroy
2019-02-08 12:52 ` [PATCH v1 06/16] powerpc/40x: add exception frame marker Christophe Leroy
2019-02-08 12:52 ` [PATCH v1 07/16] powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG Christophe Leroy
2019-02-08 12:52 ` [PATCH v1 08/16] powerpc/40x: Refactor exception entry macros by using head_32.h Christophe Leroy
2019-02-08 12:52 ` [RFC PATCH v1 09/16] powerpc/fsl_booke: ensure SPEFloatingPointException() reenables interrupts Christophe Leroy
2019-02-08 12:52 ` [RFC PATCH v1 10/16] powerpc/32: enter syscall with MSR_EE inconditionaly set Christophe Leroy
2019-02-08 12:52 ` [RFC PATCH v1 11/16] powerpc/32: Enter exceptions with MSR_EE unset Christophe Leroy
2019-02-08 12:52 ` [RFC PATCH v1 12/16] powerpc/32: get rid of COPY_EE in exception entry Christophe Leroy
2019-02-08 12:52 ` [RFC PATCH v1 13/16] powerpc: Fix 32-bit handling of MSR_EE on exceptions Christophe Leroy
2019-02-08 12:52 ` [RFC PATCH v1 14/16] powerpc/32: implement fast entry for syscalls on non BOOKE Christophe Leroy
2019-02-10 18:05   ` christophe leroy
2019-02-08 12:52 ` [RFC PATCH v1 15/16] powerpc/32: Remove MSR_PR test when returning from syscall Christophe Leroy
2019-02-08 12:52 ` [RFC PATCH v1 16/16] powerpc/32: don't do syscall stuff in transfer_to_handler on non BOOKE Christophe Leroy

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