[PATCH 0/9] ppc64 little endian updates

[PATCH 0/9] ppc64 little endian updates

[Anton Blanchard]

This patch series adds support for the new ABI, LPAR support
for H_SET_MODE and finally adds a kconfig option and defconfig.

ABIv2 support was recently committed to binutils and gcc, and
should be merged into glibc soon. There are a number of
very nice improvements including the removal of function
descriptors. Rusty's kernel patches allow binaries of either
ABI to work, easing the transition.

Alistair Popple (1):
  powerpc: Don't use ELFv2 ABI to build the kernel

Anton Blanchard (4):
  powerpc/pseries: Fix endian issues in pseries EEH code
  pseries: Add H_SET_MODE to change exception endianness
  powerpc: Add CONFIG_CPU_LITTLE_ENDIAN kernel config option.
  powerpc: Add pseries_le_defconfig

Rusty Russell (4):
  powerpc: Add TIF_ELF2ABI flag.
  powerpc: Set eflags correctly for ELF ABIv2 core dumps.
  powerpc: ELF2 binaries launched directly.
  powerpc: ELF2 binaries signal handling

 arch/powerpc/Makefile                        |   1 +
 arch/powerpc/configs/pseries_le_defconfig    | 352 +++++++++++++++++++++++++++
 arch/powerpc/include/asm/elf.h               |   4 +
 arch/powerpc/include/asm/hvcall.h            |   2 +
 arch/powerpc/include/asm/plpar_wrappers.h    |  26 ++
 arch/powerpc/include/asm/thread_info.h       |   9 +
 arch/powerpc/kernel/process.c                |  50 ++--
 arch/powerpc/kernel/signal_64.c              |  25 +-
 arch/powerpc/platforms/Kconfig.cputype       |  11 +
 arch/powerpc/platforms/pseries/eeh_pseries.c |  21 +-
 arch/powerpc/platforms/pseries/lpar.c        |  17 ++
 arch/powerpc/platforms/pseries/setup.c       |  42 ++++
 12 files changed, 527 insertions(+), 33 deletions(-)
 create mode 100644 arch/powerpc/configs/pseries_le_defconfig

-- 
1.8.3.2

[PATCH 1/9] powerpc/pseries: Fix endian issues in pseries EEH code

[Anton Blanchard]

Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/platforms/pseries/eeh_pseries.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/powerpc/platforms/pseries/eeh_pseries.c
index 7fbc25b..ccb633e 100644
--- a/arch/powerpc/platforms/pseries/eeh_pseries.c
+++ b/arch/powerpc/platforms/pseries/eeh_pseries.c
@@ -189,8 +189,9 @@ static void *pseries_eeh_of_probe(struct device_node *dn, void *flag)
 	struct eeh_dev *edev;
 	struct eeh_pe pe;
 	struct pci_dn *pdn = PCI_DN(dn);
-	const u32 *class_code, *vendor_id, *device_id;
-	const u32 *regs;
+	const __be32 *classp, *vendorp, *devicep;
+	u32 class_code;
+	const __be32 *regs;
 	u32 pcie_flags;
 	int enable = 0;
 	int ret;
@@ -201,22 +202,24 @@ static void *pseries_eeh_of_probe(struct device_node *dn, void *flag)
 		return NULL;
 
 	/* Retrieve class/vendor/device IDs */
-	class_code = of_get_property(dn, "class-code", NULL);
-	vendor_id  = of_get_property(dn, "vendor-id", NULL);
-	device_id  = of_get_property(dn, "device-id", NULL);
+	classp = of_get_property(dn, "class-code", NULL);
+	vendorp = of_get_property(dn, "vendor-id", NULL);
+	devicep = of_get_property(dn, "device-id", NULL);
 
 	/* Skip for bad OF node or PCI-ISA bridge */
-	if (!class_code || !vendor_id || !device_id)
+	if (!classp || !vendorp || !devicep)
 		return NULL;
 	if (dn->type && !strcmp(dn->type, "isa"))
 		return NULL;
 
+	class_code = of_read_number(classp, 1);
+
 	/*
 	 * Update class code and mode of eeh device. We need
 	 * correctly reflects that current device is root port
 	 * or PCIe switch downstream port.
 	 */
-	edev->class_code = *class_code;
+	edev->class_code = class_code;
 	edev->pcie_cap = pseries_eeh_find_cap(dn, PCI_CAP_ID_EXP);
 	edev->mode &= 0xFFFFFF00;
 	if ((edev->class_code >> 8) == PCI_CLASS_BRIDGE_PCI) {
@@ -243,12 +246,12 @@ static void *pseries_eeh_of_probe(struct device_node *dn, void *flag)
 	/* Initialize the fake PE */
 	memset(&pe, 0, sizeof(struct eeh_pe));
 	pe.phb = edev->phb;
-	pe.config_addr = regs[0];
+	pe.config_addr = of_read_number(regs, 1);
 
 	/* Enable EEH on the device */
 	ret = eeh_ops->set_option(&pe, EEH_OPT_ENABLE);
 	if (!ret) {
-		edev->config_addr = regs[0];
+		edev->config_addr = of_read_number(regs, 1);
 		/* Retrieve PE address */
 		edev->pe_config_addr = eeh_ops->get_pe_addr(&pe);
 		pe.addr = edev->pe_config_addr;
-- 
1.8.3.2

[PATCH 2/9] pseries: Add H_SET_MODE to change exception endianness

[Anton Blanchard]

On little endian builds call H_SET_MODE so exceptions have the
correct endianness. We need to reset the endian during kexec
so do that in the MMU hashtable clear callback.

Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/include/asm/hvcall.h         |  2 ++
 arch/powerpc/include/asm/plpar_wrappers.h | 26 +++++++++++++++++++
 arch/powerpc/platforms/pseries/lpar.c     | 17 +++++++++++++
 arch/powerpc/platforms/pseries/setup.c    | 42 +++++++++++++++++++++++++++++++
 4 files changed, 87 insertions(+)

diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index 0c7f2bf..d8b600b 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -403,6 +403,8 @@ static inline unsigned long cmo_get_page_size(void)
 extern long pSeries_enable_reloc_on_exc(void);
 extern long pSeries_disable_reloc_on_exc(void);
 
+extern long pseries_big_endian_exceptions(void);
+
 #else
 
 #define pSeries_enable_reloc_on_exc()  do {} while (0)
diff --git a/arch/powerpc/include/asm/plpar_wrappers.h b/arch/powerpc/include/asm/plpar_wrappers.h
index a63b045..12c32c5 100644
--- a/arch/powerpc/include/asm/plpar_wrappers.h
+++ b/arch/powerpc/include/asm/plpar_wrappers.h
@@ -287,6 +287,32 @@ static inline long disable_reloc_on_exceptions(void) {
 	return plpar_set_mode(0, 3, 0, 0);
 }
 
+/*
+ * Take exceptions in big endian mode on this partition
+ *
+ * Note: this call has a partition wide scope and can take a while to complete.
+ * If it returns H_LONG_BUSY_* it should be retried periodically until it
+ * returns H_SUCCESS.
+ */
+static inline long enable_big_endian_exceptions(void)
+{
+	/* mflags = 0: big endian exceptions */
+	return plpar_set_mode(0, 4, 0, 0);
+}
+
+/*
+ * Take exceptions in little endian mode on this partition
+ *
+ * Note: this call has a partition wide scope and can take a while to complete.
+ * If it returns H_LONG_BUSY_* it should be retried periodically until it
+ * returns H_SUCCESS.
+ */
+static inline long enable_little_endian_exceptions(void)
+{
+	/* mflags = 1: little endian exceptions */
+	return plpar_set_mode(1, 4, 0, 0);
+}
+
 static inline long plapr_set_ciabr(unsigned long ciabr)
 {
 	return plpar_set_mode(0, 1, ciabr, 0);
diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index 356bc75..4fca3de 100644
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -245,6 +245,23 @@ static void pSeries_lpar_hptab_clear(void)
 					&(ptes[j].pteh), &(ptes[j].ptel));
 		}
 	}
+
+#ifdef __LITTLE_ENDIAN__
+	/* Reset exceptions to big endian */
+	if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
+		long rc;
+
+		rc = pseries_big_endian_exceptions();
+		/*
+		 * At this point it is unlikely panic() will get anything
+		 * out to the user, but at least this will stop us from
+		 * continuing on further and creating an even more
+		 * difficult to debug situation.
+		 */
+		if (rc)
+			panic("Could not enable big endian exceptions");
+	}
+#endif
 }
 
 /*
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 1f97e2b..c1f1908 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -442,6 +442,32 @@ static void pSeries_machine_kexec(struct kimage *image)
 }
 #endif
 
+#ifdef __LITTLE_ENDIAN__
+long pseries_big_endian_exceptions(void)
+{
+	long rc;
+
+	while (1) {
+		rc = enable_big_endian_exceptions();
+		if (!H_IS_LONG_BUSY(rc))
+			return rc;
+		mdelay(get_longbusy_msecs(rc));
+	}
+}
+
+static long pseries_little_endian_exceptions(void)
+{
+	long rc;
+
+	while (1) {
+		rc = enable_little_endian_exceptions();
+		if (!H_IS_LONG_BUSY(rc))
+			return rc;
+		mdelay(get_longbusy_msecs(rc));
+	}
+}
+#endif
+
 static void __init pSeries_setup_arch(void)
 {
 	panic_timeout = 10;
@@ -698,6 +724,22 @@ static int __init pSeries_probe(void)
 	/* Now try to figure out if we are running on LPAR */
 	of_scan_flat_dt(pseries_probe_fw_features, NULL);
 
+#ifdef __LITTLE_ENDIAN__
+	if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
+		long rc;
+		/*
+		 * Tell the hypervisor that we want our exceptions to
+		 * be taken in little endian mode. If this fails we don't
+		 * want to use BUG() because it will trigger an exception.
+		 */
+		rc = pseries_little_endian_exceptions();
+		if (rc) {
+			ppc_md.progress("H_SET_MODE LE exception fail", 0);
+			panic("Could not enable little endian exceptions");
+		}
+	}
+#endif
+
 	if (firmware_has_feature(FW_FEATURE_LPAR))
 		hpte_init_lpar();
 	else
-- 
1.8.3.2

[PATCH 3/9] powerpc: Add TIF_ELF2ABI flag.

[Anton Blanchard]

From: Rusty Russell <rusty@rustcorp.com.au>

Little endian ppc64 is getting an exciting new ABI.  This is reflected
by the bottom two bits of e_flags in the ELF header:

	0 == legacy binaries (v1 ABI)
	1 == binaries using the old ABI (compiled with a new toolchain)
	2 == binaries using the new ABI.

We store this in a thread flag, because we need to set it in core
dumps and for signal delivery.  Our chief concern is that it doesn't
use function descriptors.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/include/asm/elf.h         | 2 ++
 arch/powerpc/include/asm/thread_info.h | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/arch/powerpc/include/asm/elf.h b/arch/powerpc/include/asm/elf.h
index cc0655a..6d0e236 100644
--- a/arch/powerpc/include/asm/elf.h
+++ b/arch/powerpc/include/asm/elf.h
@@ -86,6 +86,8 @@ typedef elf_vrregset_t elf_fpxregset_t;
 #ifdef __powerpc64__
 # define SET_PERSONALITY(ex)					\
 do {								\
+	if (((ex).e_flags & 0x3) == 2)				\
+		set_thread_flag(TIF_ELF2ABI);			\
 	if ((ex).e_ident[EI_CLASS] == ELFCLASS32)		\
 		set_thread_flag(TIF_32BIT);			\
 	else							\
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index ba7b197..05a3030 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -107,6 +107,9 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_EMULATE_STACK_STORE	16	/* Is an instruction emulation
 						for stack store? */
 #define TIF_MEMDIE		17	/* is terminating due to OOM killer */
+#if defined(CONFIG_PPC64)
+#define TIF_ELF2ABI		18	/* function descriptors must die! */
+#endif
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
@@ -185,6 +188,12 @@ static inline bool test_thread_local_flags(unsigned int flags)
 #define is_32bit_task()	(1)
 #endif
 
+#if defined(CONFIG_PPC64)
+#define is_elf2_task() (test_thread_flag(TIF_ELF2ABI))
+#else
+#define is_elf2_task() (0)
+#endif
+
 #endif	/* !__ASSEMBLY__ */
 
 #endif /* __KERNEL__ */
-- 
1.8.3.2

[PATCH 4/9] powerpc: Set eflags correctly for ELF ABIv2 core dumps.

[Anton Blanchard]

From: Rusty Russell <rusty@rustcorp.com.au>

We leave it at zero (though it could be 1) for old tasks.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/include/asm/elf.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/include/asm/elf.h b/arch/powerpc/include/asm/elf.h
index 6d0e236..935b5e7 100644
--- a/arch/powerpc/include/asm/elf.h
+++ b/arch/powerpc/include/asm/elf.h
@@ -31,6 +31,8 @@
 extern unsigned long randomize_et_dyn(unsigned long base);
 #define ELF_ET_DYN_BASE		(randomize_et_dyn(0x20000000))
 
+#define ELF_CORE_EFLAGS (is_elf2_task() ? 2 : 0)
+
 /*
  * Our registers are always unsigned longs, whether we're a 32 bit
  * process or 64 bit, on either a 64 bit or 32 bit kernel.
-- 
1.8.3.2

[PATCH 5/9] powerpc: ELF2 binaries launched directly.

[Anton Blanchard]

From: Rusty Russell <rusty@rustcorp.com.au>

No function descriptor, but we set r12 up and set TIF_RESTOREALL as it
normally isn't restored on return from syscall.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/kernel/process.c | 50 ++++++++++++++++++++++++++++++-------------
 1 file changed, 35 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 75c2d10..0650e18 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1086,25 +1086,45 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
 	regs->msr = MSR_USER;
 #else
 	if (!is_32bit_task()) {
-		unsigned long entry, toc;
+		unsigned long entry;
 
-		/* start is a relocated pointer to the function descriptor for
-		 * the elf _start routine.  The first entry in the function
-		 * descriptor is the entry address of _start and the second
-		 * entry is the TOC value we need to use.
-		 */
-		__get_user(entry, (unsigned long __user *)start);
-		__get_user(toc, (unsigned long __user *)start+1);
+		if (is_elf2_task()) {
+			/* Look ma, no function descriptors! */
+			entry = start;
 
-		/* Check whether the e_entry function descriptor entries
-		 * need to be relocated before we can use them.
-		 */
-		if (load_addr != 0) {
-			entry += load_addr;
-			toc   += load_addr;
+			/*
+			 * Ulrich says:
+			 *   The latest iteration of the ABI requires that when
+			 *   calling a function (at its global entry point),
+			 *   the caller must ensure r12 holds the entry point
+			 *   address (so that the function can quickly
+			 *   establish addressability).
+			 */
+			regs->gpr[12] = start;
+			/* Make sure that's restored on entry to userspace. */
+			set_thread_flag(TIF_RESTOREALL);
+		} else {
+			unsigned long toc;
+
+			/* start is a relocated pointer to the function
+			 * descriptor for the elf _start routine.  The first
+			 * entry in the function descriptor is the entry
+			 * address of _start and the second entry is the TOC
+			 * value we need to use.
+			 */
+			__get_user(entry, (unsigned long __user *)start);
+			__get_user(toc, (unsigned long __user *)start+1);
+
+			/* Check whether the e_entry function descriptor entries
+			 * need to be relocated before we can use them.
+			 */
+			if (load_addr != 0) {
+				entry += load_addr;
+				toc   += load_addr;
+			}
+			regs->gpr[2] = toc;
 		}
 		regs->nip = entry;
-		regs->gpr[2] = toc;
 		regs->msr = MSR_USER64;
 	} else {
 		regs->nip = start;
-- 
1.8.3.2

[PATCH 6/9] powerpc: ELF2 binaries signal handling

[Anton Blanchard]

From: Rusty Russell <rusty@rustcorp.com.au>

For the ELFv2 ABI, the hander is the entry point, not a function descriptor.
We also need to set up r12, and fortunately the fast_exception_return
exit path restores r12 for us so nothing else is required.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/kernel/signal_64.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index b3c6157..e66f67b 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -701,12 +701,6 @@ badframe:
 int handle_rt_signal64(int signr, struct k_sigaction *ka, siginfo_t *info,
 		sigset_t *set, struct pt_regs *regs)
 {
-	/* Handler is *really* a pointer to the function descriptor for
-	 * the signal routine.  The first entry in the function
-	 * descriptor is the entry address of signal and the second
-	 * entry is the TOC value we need to use.
-	 */
-	func_descr_t __user *funct_desc_ptr;
 	struct rt_sigframe __user *frame;
 	unsigned long newsp = 0;
 	long err = 0;
@@ -766,19 +760,32 @@ int handle_rt_signal64(int signr, struct k_sigaction *ka, siginfo_t *info,
 			goto badframe;
 		regs->link = (unsigned long) &frame->tramp[0];
 	}
-	funct_desc_ptr = (func_descr_t __user *) ka->sa.sa_handler;
 
 	/* Allocate a dummy caller frame for the signal handler. */
 	newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
 	err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
 
 	/* Set up "regs" so we "return" to the signal handler. */
-	err |= get_user(regs->nip, &funct_desc_ptr->entry);
+	if (is_elf2_task()) {
+		regs->nip = (unsigned long) ka->sa.sa_handler;
+		regs->gpr[12] = regs->nip;
+	} else {
+		/* Handler is *really* a pointer to the function descriptor for
+		 * the signal routine.  The first entry in the function
+		 * descriptor is the entry address of signal and the second
+		 * entry is the TOC value we need to use.
+		 */
+		func_descr_t __user *funct_desc_ptr =
+			(func_descr_t __user *) ka->sa.sa_handler;
+
+		err |= get_user(regs->nip, &funct_desc_ptr->entry);
+		err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
+	}
+
 	/* enter the signal handler in native-endian mode */
 	regs->msr &= ~MSR_LE;
 	regs->msr |= (MSR_KERNEL & MSR_LE);
 	regs->gpr[1] = newsp;
-	err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
 	regs->gpr[3] = signr;
 	regs->result = 0;
 	if (ka->sa.sa_flags & SA_SIGINFO) {
-- 
1.8.3.2

[PATCH 7/9] powerpc: Don't use ELFv2 ABI to build the kernel

[Anton Blanchard]

From: Alistair Popple <alistair@popple.id.au>

The kernel doesn't build correctly using the ELFv2 ABI.  This patch
ensures that the ELFv1 ABI is used when building a kernel with an
ELFv2 enabled compiler.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 607acf5..8a24636 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -111,6 +111,7 @@ endif
 endif
 
 CFLAGS-$(CONFIG_PPC64)	:= -mtraceback=no -mcall-aixdesc
+CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mabi=elfv1)
 CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mcmodel=medium,-mminimal-toc)
 CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mno-pointers-to-nested-functions)
 CFLAGS-$(CONFIG_PPC32)	:= -ffixed-r2 $(MULTIPLEWORD)
-- 
1.8.3.2

[PATCH 8/9] powerpc: Add CONFIG_CPU_LITTLE_ENDIAN kernel config option.

[Anton Blanchard]

With the little endian support merged, we can add the
CONFIG_CPU_LITTLE_ENDIAN kernel config option.

Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/platforms/Kconfig.cputype | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index c2a566f..132f872 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -403,3 +403,14 @@ config PPC_DOORBELL
 	default n
 
 endmenu
+
+config CPU_LITTLE_ENDIAN
+	bool "Build little endian kernel"
+	default n
+	help
+	  This option selects whether a big endian or little endian kernel will
+	  be built.
+
+	  Note that if cross compiling a little endian kernel,
+	  CROSS_COMPILE must point to a toolchain capable of targeting
+	  little endian powerpc.
-- 
1.8.3.2

[PATCH 9/9] powerpc: Add pseries_le_defconfig

[Anton Blanchard]

Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/configs/pseries_le_defconfig | 352 ++++++++++++++++++++++++++++++
 1 file changed, 352 insertions(+)
 create mode 100644 arch/powerpc/configs/pseries_le_defconfig

diff --git a/arch/powerpc/configs/pseries_le_defconfig b/arch/powerpc/configs/pseries_le_defconfig
new file mode 100644
index 0000000..62771e0
--- /dev/null
+++ b/arch/powerpc/configs/pseries_le_defconfig
@@ -0,0 +1,352 @@
+CONFIG_PPC64=y
+CONFIG_ALTIVEC=y
+CONFIG_VSX=y
+CONFIG_SMP=y
+CONFIG_NR_CPUS=2048
+CONFIG_CPU_LITTLE_ENDIAN=y
+CONFIG_SYSVIPC=y
+CONFIG_POSIX_MQUEUE=y
+CONFIG_AUDIT=y
+CONFIG_AUDITSYSCALL=y
+CONFIG_IRQ_DOMAIN_DEBUG=y
+CONFIG_NO_HZ=y
+CONFIG_HIGH_RES_TIMERS=y
+CONFIG_TASKSTATS=y
+CONFIG_TASK_DELAY_ACCT=y
+CONFIG_TASK_XACCT=y
+CONFIG_TASK_IO_ACCOUNTING=y
+CONFIG_IKCONFIG=y
+CONFIG_IKCONFIG_PROC=y
+CONFIG_CGROUPS=y
+CONFIG_CGROUP_FREEZER=y
+CONFIG_CGROUP_DEVICE=y
+CONFIG_CPUSETS=y
+CONFIG_CGROUP_CPUACCT=y
+CONFIG_BLK_DEV_INITRD=y
+# CONFIG_COMPAT_BRK is not set
+CONFIG_PROFILING=y
+CONFIG_OPROFILE=y
+CONFIG_KPROBES=y
+CONFIG_JUMP_LABEL=y
+CONFIG_MODULES=y
+CONFIG_MODULE_UNLOAD=y
+CONFIG_MODVERSIONS=y
+CONFIG_MODULE_SRCVERSION_ALL=y
+CONFIG_PARTITION_ADVANCED=y
+CONFIG_PPC_SPLPAR=y
+CONFIG_SCANLOG=m
+CONFIG_PPC_SMLPAR=y
+CONFIG_DTL=y
+# CONFIG_PPC_PMAC is not set
+CONFIG_RTAS_FLASH=m
+CONFIG_IBMEBUS=y
+CONFIG_HZ_100=y
+CONFIG_BINFMT_MISC=m
+CONFIG_PPC_TRANSACTIONAL_MEM=y
+CONFIG_KEXEC=y
+CONFIG_IRQ_ALL_CPUS=y
+CONFIG_MEMORY_HOTPLUG=y
+CONFIG_MEMORY_HOTREMOVE=y
+CONFIG_CMA=y
+CONFIG_PPC_64K_PAGES=y
+CONFIG_PPC_SUBPAGE_PROT=y
+CONFIG_SCHED_SMT=y
+CONFIG_HOTPLUG_PCI=y
+CONFIG_HOTPLUG_PCI_RPA=m
+CONFIG_HOTPLUG_PCI_RPA_DLPAR=m
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_XFRM_USER=m
+CONFIG_NET_KEY=m
+CONFIG_INET=y
+CONFIG_IP_MULTICAST=y
+CONFIG_NET_IPIP=y
+CONFIG_SYN_COOKIES=y
+CONFIG_INET_AH=m
+CONFIG_INET_ESP=m
+CONFIG_INET_IPCOMP=m
+# CONFIG_IPV6 is not set
+CONFIG_NETFILTER=y
+CONFIG_NF_CONNTRACK=m
+CONFIG_NF_CONNTRACK_EVENTS=y
+CONFIG_NF_CT_PROTO_UDPLITE=m
+CONFIG_NF_CONNTRACK_FTP=m
+CONFIG_NF_CONNTRACK_IRC=m
+CONFIG_NF_CONNTRACK_TFTP=m
+CONFIG_NF_CT_NETLINK=m
+CONFIG_NETFILTER_XT_TARGET_CLASSIFY=m
+CONFIG_NETFILTER_XT_TARGET_CONNMARK=m
+CONFIG_NETFILTER_XT_TARGET_MARK=m
+CONFIG_NETFILTER_XT_TARGET_NFLOG=m
+CONFIG_NETFILTER_XT_TARGET_NFQUEUE=m
+CONFIG_NETFILTER_XT_TARGET_TCPMSS=m
+CONFIG_NETFILTER_XT_MATCH_COMMENT=m
+CONFIG_NETFILTER_XT_MATCH_CONNBYTES=m
+CONFIG_NETFILTER_XT_MATCH_CONNLIMIT=m
+CONFIG_NETFILTER_XT_MATCH_CONNMARK=m
+CONFIG_NETFILTER_XT_MATCH_CONNTRACK=m
+CONFIG_NETFILTER_XT_MATCH_DCCP=m
+CONFIG_NETFILTER_XT_MATCH_DSCP=m
+CONFIG_NETFILTER_XT_MATCH_ESP=m
+CONFIG_NETFILTER_XT_MATCH_HASHLIMIT=m
+CONFIG_NETFILTER_XT_MATCH_HELPER=m
+CONFIG_NETFILTER_XT_MATCH_IPRANGE=m
+CONFIG_NETFILTER_XT_MATCH_LENGTH=m
+CONFIG_NETFILTER_XT_MATCH_LIMIT=m
+CONFIG_NETFILTER_XT_MATCH_MAC=m
+CONFIG_NETFILTER_XT_MATCH_MARK=m
+CONFIG_NETFILTER_XT_MATCH_MULTIPORT=m
+CONFIG_NETFILTER_XT_MATCH_OWNER=m
+CONFIG_NETFILTER_XT_MATCH_POLICY=m
+CONFIG_NETFILTER_XT_MATCH_PKTTYPE=m
+CONFIG_NETFILTER_XT_MATCH_QUOTA=m
+CONFIG_NETFILTER_XT_MATCH_RATEEST=m
+CONFIG_NETFILTER_XT_MATCH_REALM=m
+CONFIG_NETFILTER_XT_MATCH_RECENT=m
+CONFIG_NETFILTER_XT_MATCH_SCTP=m
+CONFIG_NETFILTER_XT_MATCH_STATE=m
+CONFIG_NETFILTER_XT_MATCH_STATISTIC=m
+CONFIG_NETFILTER_XT_MATCH_STRING=m
+CONFIG_NETFILTER_XT_MATCH_TCPMSS=m
+CONFIG_NETFILTER_XT_MATCH_TIME=m
+CONFIG_NETFILTER_XT_MATCH_U32=m
+CONFIG_NF_CONNTRACK_IPV4=m
+CONFIG_IP_NF_IPTABLES=m
+CONFIG_IP_NF_MATCH_AH=m
+CONFIG_IP_NF_MATCH_ECN=m
+CONFIG_IP_NF_MATCH_TTL=m
+CONFIG_IP_NF_FILTER=m
+CONFIG_IP_NF_TARGET_REJECT=m
+CONFIG_IP_NF_TARGET_ULOG=m
+CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+CONFIG_PROC_DEVICETREE=y
+CONFIG_PARPORT=m
+CONFIG_PARPORT_PC=m
+CONFIG_BLK_DEV_FD=m
+CONFIG_BLK_DEV_LOOP=y
+CONFIG_BLK_DEV_NBD=m
+CONFIG_BLK_DEV_RAM=y
+CONFIG_BLK_DEV_RAM_SIZE=65536
+CONFIG_VIRTIO_BLK=m
+CONFIG_IDE=y
+CONFIG_BLK_DEV_IDECD=y
+CONFIG_BLK_DEV_GENERIC=y
+CONFIG_BLK_DEV_AMD74XX=y
+CONFIG_BLK_DEV_SD=y
+CONFIG_CHR_DEV_ST=y
+CONFIG_BLK_DEV_SR=y
+CONFIG_BLK_DEV_SR_VENDOR=y
+CONFIG_CHR_DEV_SG=y
+CONFIG_SCSI_MULTI_LUN=y
+CONFIG_SCSI_CONSTANTS=y
+CONFIG_SCSI_FC_ATTRS=y
+CONFIG_SCSI_CXGB3_ISCSI=m
+CONFIG_SCSI_CXGB4_ISCSI=m
+CONFIG_SCSI_BNX2_ISCSI=m
+CONFIG_BE2ISCSI=m
+CONFIG_SCSI_MPT2SAS=m
+CONFIG_SCSI_IBMVSCSI=y
+CONFIG_SCSI_IBMVFC=m
+CONFIG_SCSI_SYM53C8XX_2=y
+CONFIG_SCSI_SYM53C8XX_DMA_ADDRESSING_MODE=0
+CONFIG_SCSI_IPR=y
+CONFIG_SCSI_QLA_FC=m
+CONFIG_SCSI_QLA_ISCSI=m
+CONFIG_SCSI_LPFC=m
+CONFIG_SCSI_VIRTIO=m
+CONFIG_SCSI_DH=m
+CONFIG_SCSI_DH_RDAC=m
+CONFIG_SCSI_DH_ALUA=m
+CONFIG_ATA=y
+# CONFIG_ATA_SFF is not set
+CONFIG_MD=y
+CONFIG_BLK_DEV_MD=y
+CONFIG_MD_LINEAR=y
+CONFIG_MD_RAID0=y
+CONFIG_MD_RAID1=y
+CONFIG_MD_RAID10=m
+CONFIG_MD_RAID456=m
+CONFIG_MD_MULTIPATH=m
+CONFIG_MD_FAULTY=m
+CONFIG_BLK_DEV_DM=y
+CONFIG_DM_CRYPT=m
+CONFIG_DM_SNAPSHOT=m
+CONFIG_DM_MIRROR=m
+CONFIG_DM_ZERO=m
+CONFIG_DM_MULTIPATH=m
+CONFIG_DM_MULTIPATH_QL=m
+CONFIG_DM_MULTIPATH_ST=m
+CONFIG_DM_UEVENT=y
+CONFIG_BONDING=m
+CONFIG_DUMMY=m
+CONFIG_NETCONSOLE=y
+CONFIG_NETPOLL_TRAP=y
+CONFIG_TUN=m
+CONFIG_VIRTIO_NET=m
+CONFIG_VORTEX=y
+CONFIG_ACENIC=m
+CONFIG_ACENIC_OMIT_TIGON_I=y
+CONFIG_PCNET32=y
+CONFIG_TIGON3=y
+CONFIG_CHELSIO_T1=m
+CONFIG_BE2NET=m
+CONFIG_S2IO=m
+CONFIG_IBMVETH=y
+CONFIG_EHEA=y
+CONFIG_E100=y
+CONFIG_E1000=y
+CONFIG_E1000E=y
+CONFIG_IXGB=m
+CONFIG_IXGBE=m
+CONFIG_MLX4_EN=m
+CONFIG_MYRI10GE=m
+CONFIG_QLGE=m
+CONFIG_NETXEN_NIC=m
+CONFIG_PPP=m
+CONFIG_PPP_BSDCOMP=m
+CONFIG_PPP_DEFLATE=m
+CONFIG_PPPOE=m
+CONFIG_PPP_ASYNC=m
+CONFIG_PPP_SYNC_TTY=m
+# CONFIG_INPUT_MOUSEDEV_PSAUX is not set
+CONFIG_INPUT_EVDEV=m
+CONFIG_INPUT_MISC=y
+CONFIG_INPUT_PCSPKR=m
+# CONFIG_SERIO_SERPORT is not set
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
+CONFIG_SERIAL_ICOM=m
+CONFIG_SERIAL_JSM=m
+CONFIG_HVC_CONSOLE=y
+CONFIG_HVC_RTAS=y
+CONFIG_HVCS=m
+CONFIG_VIRTIO_CONSOLE=m
+CONFIG_IBM_BSR=m
+CONFIG_GEN_RTC=y
+CONFIG_RAW_DRIVER=y
+CONFIG_MAX_RAW_DEVS=1024
+CONFIG_FB=y
+CONFIG_FIRMWARE_EDID=y
+CONFIG_FB_OF=y
+CONFIG_FB_MATROX=y
+CONFIG_FB_MATROX_MILLENIUM=y
+CONFIG_FB_MATROX_MYSTIQUE=y
+CONFIG_FB_MATROX_G=y
+CONFIG_FB_RADEON=y
+CONFIG_FB_IBM_GXT4500=y
+CONFIG_LCD_PLATFORM=m
+# CONFIG_VGA_CONSOLE is not set
+CONFIG_FRAMEBUFFER_CONSOLE=y
+CONFIG_LOGO=y
+CONFIG_HID_GYRATION=y
+CONFIG_HID_PANTHERLORD=y
+CONFIG_HID_PETALYNX=y
+CONFIG_HID_SAMSUNG=y
+CONFIG_HID_SUNPLUS=y
+CONFIG_USB_HIDDEV=y
+CONFIG_USB=y
+CONFIG_USB_MON=m
+CONFIG_USB_EHCI_HCD=y
+# CONFIG_USB_EHCI_HCD_PPC_OF is not set
+CONFIG_USB_OHCI_HCD=y
+CONFIG_USB_STORAGE=m
+CONFIG_INFINIBAND=m
+CONFIG_INFINIBAND_USER_MAD=m
+CONFIG_INFINIBAND_USER_ACCESS=m
+CONFIG_INFINIBAND_MTHCA=m
+CONFIG_INFINIBAND_EHCA=m
+CONFIG_INFINIBAND_CXGB3=m
+CONFIG_INFINIBAND_CXGB4=m
+CONFIG_MLX4_INFINIBAND=m
+CONFIG_INFINIBAND_IPOIB=m
+CONFIG_INFINIBAND_IPOIB_CM=y
+CONFIG_INFINIBAND_SRP=m
+CONFIG_INFINIBAND_ISER=m
+CONFIG_VIRTIO_PCI=m
+CONFIG_VIRTIO_BALLOON=m
+CONFIG_EXT2_FS=y
+CONFIG_EXT2_FS_XATTR=y
+CONFIG_EXT2_FS_POSIX_ACL=y
+CONFIG_EXT2_FS_SECURITY=y
+CONFIG_EXT2_FS_XIP=y
+CONFIG_EXT3_FS=y
+CONFIG_EXT3_FS_POSIX_ACL=y
+CONFIG_EXT3_FS_SECURITY=y
+CONFIG_EXT4_FS=y
+CONFIG_EXT4_FS_POSIX_ACL=y
+CONFIG_EXT4_FS_SECURITY=y
+CONFIG_REISERFS_FS=y
+CONFIG_REISERFS_FS_XATTR=y
+CONFIG_REISERFS_FS_POSIX_ACL=y
+CONFIG_REISERFS_FS_SECURITY=y
+CONFIG_JFS_FS=m
+CONFIG_JFS_POSIX_ACL=y
+CONFIG_JFS_SECURITY=y
+CONFIG_XFS_FS=m
+CONFIG_XFS_POSIX_ACL=y
+CONFIG_BTRFS_FS=m
+CONFIG_BTRFS_FS_POSIX_ACL=y
+CONFIG_NILFS2_FS=m
+CONFIG_AUTOFS4_FS=m
+CONFIG_FUSE_FS=m
+CONFIG_ISO9660_FS=y
+CONFIG_UDF_FS=m
+CONFIG_MSDOS_FS=y
+CONFIG_VFAT_FS=y
+CONFIG_PROC_KCORE=y
+CONFIG_TMPFS=y
+CONFIG_TMPFS_POSIX_ACL=y
+CONFIG_HUGETLBFS=y
+CONFIG_CRAMFS=m
+CONFIG_SQUASHFS=m
+CONFIG_SQUASHFS_XATTR=y
+CONFIG_SQUASHFS_LZO=y
+CONFIG_SQUASHFS_XZ=y
+CONFIG_PSTORE=y
+CONFIG_NFS_FS=y
+CONFIG_NFS_V3_ACL=y
+CONFIG_NFS_V4=y
+CONFIG_NFSD=m
+CONFIG_NFSD_V3_ACL=y
+CONFIG_NFSD_V4=y
+CONFIG_CIFS=m
+CONFIG_CIFS_XATTR=y
+CONFIG_CIFS_POSIX=y
+CONFIG_NLS_DEFAULT="utf8"
+CONFIG_NLS_CODEPAGE_437=y
+CONFIG_NLS_ASCII=y
+CONFIG_NLS_ISO8859_1=y
+CONFIG_NLS_UTF8=y
+CONFIG_CRC_T10DIF=y
+CONFIG_MAGIC_SYSRQ=y
+CONFIG_DEBUG_KERNEL=y
+CONFIG_DEBUG_STACK_USAGE=y
+CONFIG_DEBUG_STACKOVERFLOW=y
+CONFIG_LOCKUP_DETECTOR=y
+CONFIG_LATENCYTOP=y
+CONFIG_SCHED_TRACER=y
+CONFIG_BLK_DEV_IO_TRACE=y
+CONFIG_CODE_PATCHING_SELFTEST=y
+CONFIG_FTR_FIXUP_SELFTEST=y
+CONFIG_MSI_BITMAP_SELFTEST=y
+CONFIG_XMON=y
+CONFIG_CRYPTO_TEST=m
+CONFIG_CRYPTO_PCBC=m
+CONFIG_CRYPTO_HMAC=y
+CONFIG_CRYPTO_MICHAEL_MIC=m
+CONFIG_CRYPTO_TGR192=m
+CONFIG_CRYPTO_WP512=m
+CONFIG_CRYPTO_ANUBIS=m
+CONFIG_CRYPTO_BLOWFISH=m
+CONFIG_CRYPTO_CAST6=m
+CONFIG_CRYPTO_KHAZAD=m
+CONFIG_CRYPTO_SALSA20=m
+CONFIG_CRYPTO_SERPENT=m
+CONFIG_CRYPTO_TEA=m
+CONFIG_CRYPTO_TWOFISH=m
+CONFIG_CRYPTO_LZO=m
+# CONFIG_CRYPTO_ANSI_CPRNG is not set
+CONFIG_CRYPTO_DEV_NX=y
+CONFIG_CRYPTO_DEV_NX_ENCRYPT=m
-- 
1.8.3.2

Re: [PATCH 2/9] pseries: Add H_SET_MODE to change exception endianness

[Michael Ellerman]

On Wed, Nov 20, 2013 at 10:14:59PM +1100, Anton Blanchard wrote:
> On little endian builds call H_SET_MODE so exceptions have the
> correct endianness. We need to reset the endian during kexec
> so do that in the MMU hashtable clear callback.
> 
> Signed-off-by: Anton Blanchard <anton@samba.org>
> ---
>  arch/powerpc/include/asm/hvcall.h         |  2 ++
>  arch/powerpc/include/asm/plpar_wrappers.h | 26 +++++++++++++++++++
>  arch/powerpc/platforms/pseries/lpar.c     | 17 +++++++++++++
>  arch/powerpc/platforms/pseries/setup.c    | 42 +++++++++++++++++++++++++++++++
>  4 files changed, 87 insertions(+)
> 
> diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
> index 0c7f2bf..d8b600b 100644
> --- a/arch/powerpc/include/asm/hvcall.h
> +++ b/arch/powerpc/include/asm/hvcall.h
> @@ -403,6 +403,8 @@ static inline unsigned long cmo_get_page_size(void)
>  extern long pSeries_enable_reloc_on_exc(void);
>  extern long pSeries_disable_reloc_on_exc(void);
>  
> +extern long pseries_big_endian_exceptions(void);
> +
>  #else
>  
>  #define pSeries_enable_reloc_on_exc()  do {} while (0)
> diff --git a/arch/powerpc/include/asm/plpar_wrappers.h b/arch/powerpc/include/asm/plpar_wrappers.h
> index a63b045..12c32c5 100644
> --- a/arch/powerpc/include/asm/plpar_wrappers.h
> +++ b/arch/powerpc/include/asm/plpar_wrappers.h
> @@ -287,6 +287,32 @@ static inline long disable_reloc_on_exceptions(void) {
>  	return plpar_set_mode(0, 3, 0, 0);
>  }
>  
> +/*
> + * Take exceptions in big endian mode on this partition
> + *
> + * Note: this call has a partition wide scope and can take a while to complete.
> + * If it returns H_LONG_BUSY_* it should be retried periodically until it
> + * returns H_SUCCESS.
> + */
> +static inline long enable_big_endian_exceptions(void)
> +{
> +	/* mflags = 0: big endian exceptions */
> +	return plpar_set_mode(0, 4, 0, 0);
> +}
> +
> +/*
> + * Take exceptions in little endian mode on this partition
> + *
> + * Note: this call has a partition wide scope and can take a while to complete.
> + * If it returns H_LONG_BUSY_* it should be retried periodically until it
> + * returns H_SUCCESS.
> + */
> +static inline long enable_little_endian_exceptions(void)
> +{
> +	/* mflags = 1: little endian exceptions */
> +	return plpar_set_mode(1, 4, 0, 0);
> +}
> +

...

> diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
> index 1f97e2b..c1f1908 100644
> --- a/arch/powerpc/platforms/pseries/setup.c
> +++ b/arch/powerpc/platforms/pseries/setup.c
> @@ -442,6 +442,32 @@ static void pSeries_machine_kexec(struct kimage *image)
>  }
>  #endif

Nit picking, but I'm not sure the enable_big/little_endian_exceptions()
wrappers buy us much. And they mean you end up with essentially the same
routine twice below:
  
> +#ifdef __LITTLE_ENDIAN__
> +long pseries_big_endian_exceptions(void)
> +{
> +	long rc;
> +
> +	while (1) {
> +		rc = enable_big_endian_exceptions();
> +		if (!H_IS_LONG_BUSY(rc))
> +			return rc;
> +		mdelay(get_longbusy_msecs(rc));
> +	}
> +}
> +
> +static long pseries_little_endian_exceptions(void)
> +{
> +	long rc;
> +
> +	while (1) {
> +		rc = enable_little_endian_exceptions();
> +		if (!H_IS_LONG_BUSY(rc))
> +			return rc;
> +		mdelay(get_longbusy_msecs(rc));
> +	}
> +}
> +#endif

Whereas you could do:

static long pseries_big_endian_exceptions(bool big_endian)
{
	int mflags;
	long rc;

	mflags = big_endian ? 0 : 1;

	while (1) {
		rc = plpar_set_mode(mflags, 4, 0, 0);

		if (!H_IS_LONG_BUSY(rc))
			return rc;
		mdelay(get_longbusy_msecs(rc));
	}
}

Perhaps pseries_big_endian_exceptions(false) looks a bit odd though ..

cheers

Re: [PATCH 3/9] powerpc: Add TIF_ELF2ABI flag.

[Michael Ellerman]

On Wed, Nov 20, 2013 at 10:15:00PM +1100, Anton Blanchard wrote:
> From: Rusty Russell <rusty@rustcorp.com.au>
> 
> Little endian ppc64 is getting an exciting new ABI.  This is reflected
> by the bottom two bits of e_flags in the ELF header:
> 
> 	0 == legacy binaries (v1 ABI)
> 	1 == binaries using the old ABI (compiled with a new toolchain)
> 	2 == binaries using the new ABI.

Just to be ridiculously clear for stupid people like me, you refer here
to the "v1 ABI" and "the old ABI" - they are the same thing - right?

> diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
> index ba7b197..05a3030 100644
> --- a/arch/powerpc/include/asm/thread_info.h
> +++ b/arch/powerpc/include/asm/thread_info.h
> @@ -107,6 +107,9 @@ static inline struct thread_info *current_thread_info(void)
>  #define TIF_EMULATE_STACK_STORE	16	/* Is an instruction emulation
>  						for stack store? */
>  #define TIF_MEMDIE		17	/* is terminating due to OOM killer */
> +#if defined(CONFIG_PPC64)
> +#define TIF_ELF2ABI		18	/* function descriptors must die! */
> +#endif

This is the first TIF flag we #ifdef for 32 vs 64, is that just because
we don't want to waste a flag on 32 bit?

cheers

Re: [PATCH 4/9] powerpc: Set eflags correctly for ELF ABIv2 core dumps.

[Michael Ellerman]

On Wed, Nov 20, 2013 at 10:15:01PM +1100, Anton Blanchard wrote:
> From: Rusty Russell <rusty@rustcorp.com.au>
> 
> We leave it at zero (though it could be 1) for old tasks.

There's no issue with a v1 binary producing a v0 core dump?

I can't think of why there would be, if they are equivalent.

cheers

Re: [PATCH 8/9] powerpc: Add CONFIG_CPU_LITTLE_ENDIAN kernel config option.

[Michael Ellerman]

On Wed, Nov 20, 2013 at 10:15:05PM +1100, Anton Blanchard wrote:
> With the little endian support merged, we can add the
> CONFIG_CPU_LITTLE_ENDIAN kernel config option.

This appears to do nothing, but the Makefile bits were already added in
commit d72b080 "powerpc: Add ability to build little endian kernels".

cheers

Re: [PATCH 3/9] powerpc: Add TIF_ELF2ABI flag.

[Rusty Russell]

Michael Ellerman <mpe@ellerman.id.au> writes:
> On Wed, Nov 20, 2013 at 10:15:00PM +1100, Anton Blanchard wrote:
>> From: Rusty Russell <rusty@rustcorp.com.au>
>> 
>> Little endian ppc64 is getting an exciting new ABI.  This is reflected
>> by the bottom two bits of e_flags in the ELF header:
>> 
>> 	0 == legacy binaries (v1 ABI)
>> 	1 == binaries using the old ABI (compiled with a new toolchain)
>> 	2 == binaries using the new ABI.
>
> Just to be ridiculously clear for stupid people like me, you refer here
> to the "v1 ABI" and "the old ABI" - they are the same thing - right?

Sorry for delay, was off for a week.

Yes, same thing.

>> diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
>> index ba7b197..05a3030 100644
>> --- a/arch/powerpc/include/asm/thread_info.h
>> +++ b/arch/powerpc/include/asm/thread_info.h
>> @@ -107,6 +107,9 @@ static inline struct thread_info *current_thread_info(void)
>>  #define TIF_EMULATE_STACK_STORE	16	/* Is an instruction emulation
>>  						for stack store? */
>>  #define TIF_MEMDIE		17	/* is terminating due to OOM killer */
>> +#if defined(CONFIG_PPC64)
>> +#define TIF_ELF2ABI		18	/* function descriptors must die! */
>> +#endif
>
> This is the first TIF flag we #ifdef for 32 vs 64, is that just because
> we don't want to waste a flag on 32 bit?

No, it's because I wanted to make damn sure that there wasn't anyone
testing this in 32-bit code, since ELF2 is currently a 64-bit only
option.

Cheers,
Rusty.