* COP2 unaligned -> SIGBUS
@ 2009-11-23 6:31 Mikael Starvik
2009-11-23 11:38 ` Ralf Baechle
0 siblings, 1 reply; 6+ messages in thread
From: Mikael Starvik @ 2009-11-23 6:31 UTC (permalink / raw)
To: linux-mips
Since there are now at least two users of cop2 I propose the following:
Regards
/Mikael
Index: unaligned.c
===================================================================
RCS file: /usr/local/cvs/linux/os/linux-2.6/arch/mips/kernel/unaligned.c,v
retrieving revision 1.12
retrieving revision 1.13
diff -u -r1.12 -r1.13
--- unaligned.c 15 Jun 2009 16:00:57 -0000 1.12
+++ unaligned.c 23 Nov 2009 06:26:04 -0000 1.13
@@ -446,22 +446,15 @@
case ldc1_op:
case swc1_op:
case sdc1_op:
- /*
- * I herewith declare: this does not happen. So send SIGBUS.
- */
- goto sigbus;
-
case lwc2_op:
case ldc2_op:
case swc2_op:
case sdc2_op:
/*
- * These are the coprocessor 2 load/stores. The current
- * implementations don't use cp2 and cp2 should always be
- * disabled in c0_status. So send SIGILL.
- * (No longer true: The Sony Praystation uses cp2 for
- * 3D matrix operations. Dunno if that thingy has a MMU ...)
+ * I herewith declare: this does not happen. So send SIGBUS.
*/
+ goto sigbus;
+
default:
/*
* Pheeee... We encountered an yet unknown instruction or
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: COP2 unaligned -> SIGBUS
2009-11-23 6:31 COP2 unaligned -> SIGBUS Mikael Starvik
@ 2009-11-23 11:38 ` Ralf Baechle
2009-11-23 11:56 ` Ralf Baechle
0 siblings, 1 reply; 6+ messages in thread
From: Ralf Baechle @ 2009-11-23 11:38 UTC (permalink / raw)
To: Mikael Starvik; +Cc: linux-mips
On Mon, Nov 23, 2009 at 07:31:28AM +0100, Mikael Starvik wrote:
> Since there are now at least two users of cop2 I propose the following:
Yes, the comment is not quite correct. CP2 has always been available for
application specific extensions and a few imlementations have made use of
that. I'll update the comment. Oh and the Praystation has a TLB.
Thanks!
Ralf
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: COP2 unaligned -> SIGBUS
2009-11-23 11:38 ` Ralf Baechle
@ 2009-11-23 11:56 ` Ralf Baechle
2009-11-24 18:17 ` Ralf Baechle
0 siblings, 1 reply; 6+ messages in thread
From: Ralf Baechle @ 2009-11-23 11:56 UTC (permalink / raw)
To: Mikael Starvik; +Cc: linux-mips, David Daney
On Mon, Nov 23, 2009 at 11:38:20AM +0000, Ralf Baechle wrote:
> > Since there are now at least two users of cop2 I propose the following:
>
> Yes, the comment is not quite correct. CP2 has always been available for
> application specific extensions and a few imlementations have made use of
> that. I'll update the comment. Oh and the Praystation has a TLB.
On 2nd thought - there is one user of CU2 in the kernel - the Cavium support.
Nothing else in the stock Linux/MIPS kernel will ever enable c0_status.cu2,
so the attempt to execute a CP2 load or store instruction would result in a
Coprocessor Unusable exception which whould result in a SIGILL being
delivered to the offending process. On Cavium the instructions COP2 is
documented to not deliver any exceptions so there isn't really anything
that would need to be changed.
David - I think we should try to get rid of the processor specifics from
this core code so probably having notifiers to run on Address Error or
Coprocessor Unusable exceptions would be a solution? I also want to get
rid of the Cavium #ifdef from traps.c.
Ralf
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: COP2 unaligned -> SIGBUS
2009-11-23 11:56 ` Ralf Baechle
@ 2009-11-24 18:17 ` Ralf Baechle
2009-11-24 18:40 ` SV: " Mikael Starvik
0 siblings, 1 reply; 6+ messages in thread
From: Ralf Baechle @ 2009-11-24 18:17 UTC (permalink / raw)
To: Mikael Starvik; +Cc: linux-mips, David Daney
On Mon, Nov 23, 2009 at 11:56:19AM +0000, Ralf Baechle wrote:
>
> > > Since there are now at least two users of cop2 I propose the following:
> >
> > Yes, the comment is not quite correct. CP2 has always been available for
> > application specific extensions and a few imlementations have made use of
> > that. I'll update the comment. Oh and the Praystation has a TLB.
>
> On 2nd thought - there is one user of CU2 in the kernel - the Cavium support.
>
> Nothing else in the stock Linux/MIPS kernel will ever enable c0_status.cu2,
> so the attempt to execute a CP2 load or store instruction would result in a
> Coprocessor Unusable exception which whould result in a SIGILL being
> delivered to the offending process. On Cavium the instructions COP2 is
> documented to not deliver any exceptions so there isn't really anything
> that would need to be changed.
>
> David - I think we should try to get rid of the processor specifics from
> this core code so probably having notifiers to run on Address Error or
> Coprocessor Unusable exceptions would be a solution? I also want to get
> rid of the Cavium #ifdef from traps.c.
So how about this patch below? It uses notifiers as a halfway clean and
reasonably fast hook mechanism. Might be over-engineered though :-)
Compiles but not runtime tested.
Ralf
From: Ralf Baechle <ralf@linux-mips.org>
MIPS: COP2 cleanups.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/cavium-octeon/Makefile b/arch/mips/cavium-octeon/Makefile
index 1394362..3e98763 100644
--- a/arch/mips/cavium-octeon/Makefile
+++ b/arch/mips/cavium-octeon/Makefile
@@ -9,7 +9,7 @@
# Copyright (C) 2005-2009 Cavium Networks
#
-obj-y := setup.o serial.o octeon-platform.o octeon-irq.o csrc-octeon.o
+obj-y := cpu.o setup.o serial.o octeon-platform.o octeon-irq.o csrc-octeon.o
obj-y += dma-octeon.o flash_setup.o
obj-y += octeon-memcpy.o
diff --git a/arch/mips/cavium-octeon/cpu.c b/arch/mips/cavium-octeon/cpu.c
new file mode 100644
index 0000000..b6df538
--- /dev/null
+++ b/arch/mips/cavium-octeon/cpu.c
@@ -0,0 +1,52 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009 Wind River Systems,
+ * written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#include <linux/init.h>
+#include <linux/irqflags.h>
+#include <linux/notifier.h>
+#include <linux/prefetch.h>
+#include <linux/sched.h>
+
+#include <asm/cop2.h>
+#include <asm/current.h>
+#include <asm/mipsregs.h>
+#include <asm/page.h>
+#include <asm/octeon/octeon.h>
+
+static int cnmips_cu2_call(struct notifier_block *nfb, unsigned long action,
+ void *data)
+{
+ unsigned long flags;
+ unsigned int status;
+
+ switch (action) {
+ case CU2_EXCEPTION:
+ prefetch(¤t->thread.cp2);
+ local_irq_save(flags);
+ KSTK_STATUS(current) |= ST0_CU2;
+ status = read_c0_status();
+ write_c0_status(status | ST0_CU2);
+ octeon_cop2_restore(&(current->thread.cp2));
+ write_c0_status(status & ~ST0_CU2);
+ local_irq_restore(flags);
+
+ return NOTIFY_BAD; /* Don't call default notifier */
+ }
+
+ return NOTIFY_OK; /* Let default notifier send signals */
+}
+
+static struct notifier_block cnmips_cu2_notifier = {
+ .notifier_call = cnmips_cu2_call,
+};
+
+static int cnmips_cu2_setup(void)
+{
+ return register_cu2_notifier(&cnmips_cu2_notifier);
+}
+early_initcall(cnmips_cu2_setup);
diff --git a/arch/mips/include/asm/cop2.h b/arch/mips/include/asm/cop2.h
new file mode 100644
index 0000000..6b04c98
--- /dev/null
+++ b/arch/mips/include/asm/cop2.h
@@ -0,0 +1,23 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009 Wind River Systems,
+ * written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#ifndef __ASM_COP2_H
+#define __ASM_COP2_H
+
+enum cu2_ops {
+ CU2_EXCEPTION,
+ CU2_LWC2_OP,
+ CU2_LDC2_OP,
+ CU2_SWC2_OP,
+ CU2_SDC2_OP,
+};
+
+extern int register_cu2_notifier(struct notifier_block *nb);
+extern int cu2_notifier_call_chain(unsigned long val, void *v);
+
+#endif /* __ASM_COP2_H */
diff --git a/arch/mips/include/asm/octeon/octeon.h b/arch/mips/include/asm/octeon/octeon.h
index cac9b1a..4d0a8c6 100644
--- a/arch/mips/include/asm/octeon/octeon.h
+++ b/arch/mips/include/asm/octeon/octeon.h
@@ -47,6 +47,7 @@ struct octeon_cop2_state;
extern unsigned long octeon_crypto_enable(struct octeon_cop2_state *state);
extern void octeon_crypto_disable(struct octeon_cop2_state *state,
unsigned long flags);
+extern asmlinkage void octeon_cop2_restore(struct octeon_cop2_state *task);
extern void octeon_init_cvmcount(void);
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 0a18b4c..2c5c3a2 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -25,10 +25,12 @@
#include <linux/ptrace.h>
#include <linux/kgdb.h>
#include <linux/kdebug.h>
+#include <linux/notifier.h>
#include <asm/bootinfo.h>
#include <asm/branch.h>
#include <asm/break.h>
+#include <asm/cop2.h>
#include <asm/cpu.h>
#include <asm/dsp.h>
#include <asm/fpu.h>
@@ -79,10 +81,6 @@ extern asmlinkage void handle_reserved(void);
extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
struct mips_fpu_struct *ctx, int has_fpu);
-#ifdef CONFIG_CPU_CAVIUM_OCTEON
-extern asmlinkage void octeon_cop2_restore(struct octeon_cop2_state *task);
-#endif
-
void (*board_be_init)(void);
int (*board_be_handler)(struct pt_regs *regs, int is_fixup);
void (*board_nmi_handler_setup)(void);
@@ -857,6 +855,44 @@ static void mt_ase_fp_affinity(void)
#endif /* CONFIG_MIPS_MT_FPAFF */
}
+/*
+ * No lock; only written during early bootup by CPU 0.
+ */
+static RAW_NOTIFIER_HEAD(cu2_chain);
+
+int __ref register_cu2_notifier(struct notifier_block *nb)
+{
+ return raw_notifier_chain_register(&cu2_chain, nb);
+}
+
+int cu2_notifier_call_chain(unsigned long val, void *v)
+{
+ return raw_notifier_call_chain(&cu2_chain, val, v);
+}
+
+static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
+ void *data)
+{
+ struct pt_regs *regs = data;
+
+ switch (action) {
+ default:
+ die_if_kernel("Unhandled kernel unaligned access or invalid "
+ "instruction", regs);
+ /* Fall through */
+
+ case CU2_EXCEPTION:
+ force_sig(SIGILL, current);
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block default_cu2_notifier = {
+ .notifier_call = default_cu2_call,
+ .priority = 0x80000000, /* Run last */
+};
+
asmlinkage void do_cpu(struct pt_regs *regs)
{
unsigned int __user *epc;
@@ -920,17 +956,9 @@ asmlinkage void do_cpu(struct pt_regs *regs)
return;
case 2:
-#ifdef CONFIG_CPU_CAVIUM_OCTEON
- prefetch(¤t->thread.cp2);
- local_irq_save(flags);
- KSTK_STATUS(current) |= ST0_CU2;
- status = read_c0_status();
- write_c0_status(status | ST0_CU2);
- octeon_cop2_restore(&(current->thread.cp2));
- write_c0_status(status & ~ST0_CU2);
- local_irq_restore(flags);
- return;
-#endif
+ raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs);
+ break;
+
case 3:
break;
}
@@ -1760,4 +1788,6 @@ void __init trap_init(void)
flush_tlb_handlers();
sort_extable(__start___dbe_table, __stop___dbe_table);
+
+ register_cu2_notifier(&default_cu2_notifier);
}
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index 67bd626..69b039c 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -81,6 +81,7 @@
#include <asm/asm.h>
#include <asm/branch.h>
#include <asm/byteorder.h>
+#include <asm/cop2.h>
#include <asm/inst.h>
#include <asm/uaccess.h>
#include <asm/system.h>
@@ -451,17 +452,27 @@ static void emulate_load_store_insn(struct pt_regs *regs,
*/
goto sigbus;
+ /*
+ * COP2 is available to implementor for application specific use.
+ * It's up to applications to register a notifier chain and do
+ * whatever they have to do, including possible sending of signals.
+ */
case lwc2_op:
+ cu2_notifier_call_chain(CU2_LWC2_OP, regs);
+ break;
+
case ldc2_op:
+ cu2_notifier_call_chain(CU2_LDC2_OP, regs);
+ break;
+
case swc2_op:
+ cu2_notifier_call_chain(CU2_SWC2_OP, regs);
+ break;
+
case sdc2_op:
- /*
- * These are the coprocessor 2 load/stores. The current
- * implementations don't use cp2 and cp2 should always be
- * disabled in c0_status. So send SIGILL.
- * (No longer true: The Sony Praystation uses cp2 for
- * 3D matrix operations. Dunno if that thingy has a MMU ...)
- */
+ cu2_notifier_call_chain(CU2_SDC2_OP, regs);
+ break;
+
default:
/*
* Pheeee... We encountered an yet unknown instruction or
^ permalink raw reply related [flat|nested] 6+ messages in thread
* SV: COP2 unaligned -> SIGBUS
2009-11-24 18:17 ` Ralf Baechle
@ 2009-11-24 18:40 ` Mikael Starvik
2009-11-24 22:12 ` Ralf Baechle
0 siblings, 1 reply; 6+ messages in thread
From: Mikael Starvik @ 2009-11-24 18:40 UTC (permalink / raw)
To: Ralf Baechle; +Cc: linux-mips, David Daney
Looks good! An alternative would of course be to add a COP2 kernel config that are selected by some MIPS machines.
/Mikael
________________________________________
Från: Ralf Baechle [ralf@linux-mips.org]
Skickat: den 24 november 2009 19:17
Till: Mikael Starvik
Kopia: linux-mips@linux-mips.org; David Daney
Ämne: Re: COP2 unaligned -> SIGBUS
On Mon, Nov 23, 2009 at 11:56:19AM +0000, Ralf Baechle wrote:
>
> > > Since there are now at least two users of cop2 I propose the following:
> >
> > Yes, the comment is not quite correct. CP2 has always been available for
> > application specific extensions and a few imlementations have made use of
> > that. I'll update the comment. Oh and the Praystation has a TLB.
>
> On 2nd thought - there is one user of CU2 in the kernel - the Cavium support.
>
> Nothing else in the stock Linux/MIPS kernel will ever enable c0_status.cu2,
> so the attempt to execute a CP2 load or store instruction would result in a
> Coprocessor Unusable exception which whould result in a SIGILL being
> delivered to the offending process. On Cavium the instructions COP2 is
> documented to not deliver any exceptions so there isn't really anything
> that would need to be changed.
>
> David - I think we should try to get rid of the processor specifics from
> this core code so probably having notifiers to run on Address Error or
> Coprocessor Unusable exceptions would be a solution? I also want to get
> rid of the Cavium #ifdef from traps.c.
So how about this patch below? It uses notifiers as a halfway clean and
reasonably fast hook mechanism. Might be over-engineered though :-)
Compiles but not runtime tested.
Ralf
From: Ralf Baechle <ralf@linux-mips.org>
MIPS: COP2 cleanups.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/cavium-octeon/Makefile b/arch/mips/cavium-octeon/Makefile
index 1394362..3e98763 100644
--- a/arch/mips/cavium-octeon/Makefile
+++ b/arch/mips/cavium-octeon/Makefile
@@ -9,7 +9,7 @@
# Copyright (C) 2005-2009 Cavium Networks
#
-obj-y := setup.o serial.o octeon-platform.o octeon-irq.o csrc-octeon.o
+obj-y := cpu.o setup.o serial.o octeon-platform.o octeon-irq.o csrc-octeon.o
obj-y += dma-octeon.o flash_setup.o
obj-y += octeon-memcpy.o
diff --git a/arch/mips/cavium-octeon/cpu.c b/arch/mips/cavium-octeon/cpu.c
new file mode 100644
index 0000000..b6df538
--- /dev/null
+++ b/arch/mips/cavium-octeon/cpu.c
@@ -0,0 +1,52 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009 Wind River Systems,
+ * written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#include <linux/init.h>
+#include <linux/irqflags.h>
+#include <linux/notifier.h>
+#include <linux/prefetch.h>
+#include <linux/sched.h>
+
+#include <asm/cop2.h>
+#include <asm/current.h>
+#include <asm/mipsregs.h>
+#include <asm/page.h>
+#include <asm/octeon/octeon.h>
+
+static int cnmips_cu2_call(struct notifier_block *nfb, unsigned long action,
+ void *data)
+{
+ unsigned long flags;
+ unsigned int status;
+
+ switch (action) {
+ case CU2_EXCEPTION:
+ prefetch(¤t->thread.cp2);
+ local_irq_save(flags);
+ KSTK_STATUS(current) |= ST0_CU2;
+ status = read_c0_status();
+ write_c0_status(status | ST0_CU2);
+ octeon_cop2_restore(&(current->thread.cp2));
+ write_c0_status(status & ~ST0_CU2);
+ local_irq_restore(flags);
+
+ return NOTIFY_BAD; /* Don't call default notifier */
+ }
+
+ return NOTIFY_OK; /* Let default notifier send signals */
+}
+
+static struct notifier_block cnmips_cu2_notifier = {
+ .notifier_call = cnmips_cu2_call,
+};
+
+static int cnmips_cu2_setup(void)
+{
+ return register_cu2_notifier(&cnmips_cu2_notifier);
+}
+early_initcall(cnmips_cu2_setup);
diff --git a/arch/mips/include/asm/cop2.h b/arch/mips/include/asm/cop2.h
new file mode 100644
index 0000000..6b04c98
--- /dev/null
+++ b/arch/mips/include/asm/cop2.h
@@ -0,0 +1,23 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009 Wind River Systems,
+ * written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#ifndef __ASM_COP2_H
+#define __ASM_COP2_H
+
+enum cu2_ops {
+ CU2_EXCEPTION,
+ CU2_LWC2_OP,
+ CU2_LDC2_OP,
+ CU2_SWC2_OP,
+ CU2_SDC2_OP,
+};
+
+extern int register_cu2_notifier(struct notifier_block *nb);
+extern int cu2_notifier_call_chain(unsigned long val, void *v);
+
+#endif /* __ASM_COP2_H */
diff --git a/arch/mips/include/asm/octeon/octeon.h b/arch/mips/include/asm/octeon/octeon.h
index cac9b1a..4d0a8c6 100644
--- a/arch/mips/include/asm/octeon/octeon.h
+++ b/arch/mips/include/asm/octeon/octeon.h
@@ -47,6 +47,7 @@ struct octeon_cop2_state;
extern unsigned long octeon_crypto_enable(struct octeon_cop2_state *state);
extern void octeon_crypto_disable(struct octeon_cop2_state *state,
unsigned long flags);
+extern asmlinkage void octeon_cop2_restore(struct octeon_cop2_state *task);
extern void octeon_init_cvmcount(void);
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 0a18b4c..2c5c3a2 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -25,10 +25,12 @@
#include <linux/ptrace.h>
#include <linux/kgdb.h>
#include <linux/kdebug.h>
+#include <linux/notifier.h>
#include <asm/bootinfo.h>
#include <asm/branch.h>
#include <asm/break.h>
+#include <asm/cop2.h>
#include <asm/cpu.h>
#include <asm/dsp.h>
#include <asm/fpu.h>
@@ -79,10 +81,6 @@ extern asmlinkage void handle_reserved(void);
extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
struct mips_fpu_struct *ctx, int has_fpu);
-#ifdef CONFIG_CPU_CAVIUM_OCTEON
-extern asmlinkage void octeon_cop2_restore(struct octeon_cop2_state *task);
-#endif
-
void (*board_be_init)(void);
int (*board_be_handler)(struct pt_regs *regs, int is_fixup);
void (*board_nmi_handler_setup)(void);
@@ -857,6 +855,44 @@ static void mt_ase_fp_affinity(void)
#endif /* CONFIG_MIPS_MT_FPAFF */
}
+/*
+ * No lock; only written during early bootup by CPU 0.
+ */
+static RAW_NOTIFIER_HEAD(cu2_chain);
+
+int __ref register_cu2_notifier(struct notifier_block *nb)
+{
+ return raw_notifier_chain_register(&cu2_chain, nb);
+}
+
+int cu2_notifier_call_chain(unsigned long val, void *v)
+{
+ return raw_notifier_call_chain(&cu2_chain, val, v);
+}
+
+static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
+ void *data)
+{
+ struct pt_regs *regs = data;
+
+ switch (action) {
+ default:
+ die_if_kernel("Unhandled kernel unaligned access or invalid "
+ "instruction", regs);
+ /* Fall through */
+
+ case CU2_EXCEPTION:
+ force_sig(SIGILL, current);
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block default_cu2_notifier = {
+ .notifier_call = default_cu2_call,
+ .priority = 0x80000000, /* Run last */
+};
+
asmlinkage void do_cpu(struct pt_regs *regs)
{
unsigned int __user *epc;
@@ -920,17 +956,9 @@ asmlinkage void do_cpu(struct pt_regs *regs)
return;
case 2:
-#ifdef CONFIG_CPU_CAVIUM_OCTEON
- prefetch(¤t->thread.cp2);
- local_irq_save(flags);
- KSTK_STATUS(current) |= ST0_CU2;
- status = read_c0_status();
- write_c0_status(status | ST0_CU2);
- octeon_cop2_restore(&(current->thread.cp2));
- write_c0_status(status & ~ST0_CU2);
- local_irq_restore(flags);
- return;
-#endif
+ raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs);
+ break;
+
case 3:
break;
}
@@ -1760,4 +1788,6 @@ void __init trap_init(void)
flush_tlb_handlers();
sort_extable(__start___dbe_table, __stop___dbe_table);
+
+ register_cu2_notifier(&default_cu2_notifier);
}
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index 67bd626..69b039c 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -81,6 +81,7 @@
#include <asm/asm.h>
#include <asm/branch.h>
#include <asm/byteorder.h>
+#include <asm/cop2.h>
#include <asm/inst.h>
#include <asm/uaccess.h>
#include <asm/system.h>
@@ -451,17 +452,27 @@ static void emulate_load_store_insn(struct pt_regs *regs,
*/
goto sigbus;
+ /*
+ * COP2 is available to implementor for application specific use.
+ * It's up to applications to register a notifier chain and do
+ * whatever they have to do, including possible sending of signals.
+ */
case lwc2_op:
+ cu2_notifier_call_chain(CU2_LWC2_OP, regs);
+ break;
+
case ldc2_op:
+ cu2_notifier_call_chain(CU2_LDC2_OP, regs);
+ break;
+
case swc2_op:
+ cu2_notifier_call_chain(CU2_SWC2_OP, regs);
+ break;
+
case sdc2_op:
- /*
- * These are the coprocessor 2 load/stores. The current
- * implementations don't use cp2 and cp2 should always be
- * disabled in c0_status. So send SIGILL.
- * (No longer true: The Sony Praystation uses cp2 for
- * 3D matrix operations. Dunno if that thingy has a MMU ...)
- */
+ cu2_notifier_call_chain(CU2_SDC2_OP, regs);
+ break;
+
default:
/*
* Pheeee... We encountered an yet unknown instruction or
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: SV: COP2 unaligned -> SIGBUS
2009-11-24 18:40 ` SV: " Mikael Starvik
@ 2009-11-24 22:12 ` Ralf Baechle
0 siblings, 0 replies; 6+ messages in thread
From: Ralf Baechle @ 2009-11-24 22:12 UTC (permalink / raw)
To: Mikael Starvik; +Cc: linux-mips, David Daney
On Tue, Nov 24, 2009 at 07:40:38PM +0100, Mikael Starvik wrote:
> From: Mikael Starvik <mikael.starvik@axis.com>
> Date: Tue, 24 Nov 2009 19:40:38 +0100
> To: Ralf Baechle <ralf@linux-mips.org>
> CC: "linux-mips@linux-mips.org" <linux-mips@linux-mips.org>,
> David Daney <ddaney@caviumnetworks.com>
> Subject: SV: COP2 unaligned -> SIGBUS
> Content-Type: text/plain; charset="iso-8859-1"
>
> Looks good! An alternative would of course be to add a COP2 kernel config that are selected by some MIPS machines.
And folks, please stop replying with a full patch quoted. Full quote at
the end was always bloody annoying but if it's a even a patch it results
in a bogus entry in patchwork being created.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2009-11-24 22:12 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2009-11-23 6:31 COP2 unaligned -> SIGBUS Mikael Starvik
2009-11-23 11:38 ` Ralf Baechle
2009-11-23 11:56 ` Ralf Baechle
2009-11-24 18:17 ` Ralf Baechle
2009-11-24 18:40 ` SV: " Mikael Starvik
2009-11-24 22:12 ` Ralf Baechle
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