Subject: + x86-fix-trigger_all_cpu_backtrace-implementation.patch added to -mm tree
To: walken@xxxxxxxxxx,hpa@xxxxxxxxx,mingo@xxxxxxxxxx,tglx@xxxxxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Mon, 10 Jun 2013 14:53:10 -0700
The patch titled
Subject: x86: fix trigger_all_cpu_backtrace() implementation
has been added to the -mm tree. Its filename is
x86-fix-trigger_all_cpu_backtrace-implementation.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Michel Lespinasse <walken@xxxxxxxxxx>
Subject: x86: fix trigger_all_cpu_backtrace() implementation
Fix the x86 implementation of trigger_all_cpu_backtrace(), which was
previously (accidentally, as far as I can tell) disabled to always return
false as on architectures that do not implement this function.
trigger_all_cpu_backtrace(), as defined in include/linux/nmi.h, should
call arch_trigger_all_cpu_backtrace() if available, or return false if the
underlying arch doesn't implement this function.
x86 did provide a suitable arch_trigger_all_cpu_backtrace()
implementation, but it wasn't actually being used because it was declared
in asm/nmi.h, which linux/nmi.h doesn't include. Also, linux/nmi.h
couldn't easily be fixed by including asm/nmi.h, because that file is not
available on all architectures.
I am proposing to fix this by moving the x86 definition of
arch_trigger_all_cpu_backtrace() to asm/irq.h.
Tested: echo l > /proc/sysrq-trigger
Before the change, this uses a fallback implementation which shows
backtraces on active CPUs (using smp_call_function_interrupt()).
After the change, this shows NMI backtraces on all CPUs.
Signed-off-by: Michel Lespinasse <walken@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/irq.h | 5 +++++
arch/x86/include/asm/nmi.h | 4 +---
arch/x86/kernel/apic/hw_nmi.c | 1 +
3 files changed, 7 insertions(+), 3 deletions(-)
diff -puN arch/x86/include/asm/irq.h~x86-fix-trigger_all_cpu_backtrace-implementation arch/x86/include/asm/irq.h
--- a/arch/x86/include/asm/irq.h~x86-fix-trigger_all_cpu_backtrace-implementation
+++ a/arch/x86/include/asm/irq.h
@@ -41,4 +41,9 @@ extern int vector_used_by_percpu_irq(uns
extern void init_ISA_irqs(void);
+#ifdef CONFIG_X86_LOCAL_APIC
+void arch_trigger_all_cpu_backtrace(void);
+#define arch_trigger_all_cpu_backtrace arch_trigger_all_cpu_backtrace
+#endif
+
#endif /* _ASM_X86_IRQ_H */
diff -puN arch/x86/include/asm/nmi.h~x86-fix-trigger_all_cpu_backtrace-implementation arch/x86/include/asm/nmi.h
--- a/arch/x86/include/asm/nmi.h~x86-fix-trigger_all_cpu_backtrace-implementation
+++ a/arch/x86/include/asm/nmi.h
@@ -18,9 +18,7 @@ extern int proc_nmi_enabled(struct ctl_t
void __user *, size_t *, loff_t *);
extern int unknown_nmi_panic;
-void arch_trigger_all_cpu_backtrace(void);
-#define arch_trigger_all_cpu_backtrace arch_trigger_all_cpu_backtrace
-#endif
+#endif /* CONFIG_X86_LOCAL_APIC */
#define NMI_FLAG_FIRST 1
diff -puN arch/x86/kernel/apic/hw_nmi.c~x86-fix-trigger_all_cpu_backtrace-implementation arch/x86/kernel/apic/hw_nmi.c
--- a/arch/x86/kernel/apic/hw_nmi.c~x86-fix-trigger_all_cpu_backtrace-implementation
+++ a/arch/x86/kernel/apic/hw_nmi.c
@@ -9,6 +9,7 @@
*
*/
#include <asm/apic.h>
+#include <asm/nmi.h>
#include <linux/cpumask.h>
#include <linux/kdebug.h>
_
Patches currently in -mm which might be from walken@xxxxxxxxxx are
linux-next.patch
x86-fix-trigger_all_cpu_backtrace-implementation.patch
lockdep-introduce-lock_acquire_exclusive-shared-helper-macros.patch
lglock-update-lockdep-annotations-to-report-recursive-local-locks.patch
mm-remove-free_area_cache.patch
mm-nommuc-add-additional-check-for-vread-just-like-vwrite-has-done.patch
mm-change-signature-of-free_reserved_area-to-fix-building-warnings.patch
mm-enhance-free_reserved_area-to-support-poisoning-memory-with-zero.patch
mm-arm64-kill-poison_init_mem.patch
mm-x86-use-free_reserved_area-to-simplify-code.patch
mm-tile-use-common-help-functions-to-free-reserved-pages.patch
mm-fix-some-trivial-typos-in-comments.patch
mm-use-managed_pages-to-calculate-default-zonelist-order.patch
mm-accurately-calculate-zone-managed_pages-for-highmem-zones.patch
mm-use-a-dedicated-lock-to-protect-totalram_pages-and-zone-managed_pages.patch
mm-make-__free_pages_bootmem-only-available-at-boot-time.patch
mm-correctly-update-zone-managed_pages.patch
mm-correctly-update-zone-managed_pages-fix.patch
mm-concentrate-modification-of-totalram_pages-into-the-mm-core.patch
mm-report-available-pages-as-memtotal-for-each-numa-node.patch
mm-introduce-helper-function-mem_init_print_info-to-simplify-mem_init.patch
mm-kill-global-variable-num_physpages.patch
mutex-subsystem-synchro-test-module.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
