2016-03-03 11:03:31

by Hidehiro Kawai

[permalink] [raw]
Subject: [v3 PATCH 0/3] Use nmi_panic() in panic on NMI case

commit 1717f2096b54 ("panic, x86: Fix re-entrance problem due to
panic on NMI") and commit 58c5661f2144 ("panic, x86: Allow CPUs to
save registers even if looping in NMI context") introduced nmi_panic()
which prevents concurrent/recursive execution of panic(). It also
saves registers for the crash dump on x86.

However, there are some cases where NMI handlers still use panic().
This patch set partially replaces them with nmi_panic() in those
cases.

Changes since v2 (https://lkml.org/lkml/2016/3/2/173):
- Make nmi_panic receive a single string instead of printf style args
(PATCH 1/3)

Changes since v1 (https://lkml.org/lkml/2016/2/29/858):
- Replace nmi_panic() macro with a function version instead of
exporting symbols referred by the macro (PATCH 1/3)
- Improve the patch descriptions (PATCH 2/3 and 3/3)
- Do small cleanups (PATCH 3/3)

---
Even if applying this patch set, some NMI or similar handlers (e.g.
MCE handler) remains to use panic(). This is because I can't test
them well and actual problems won't happen. For example, the
possibility that normal panic and panic on MCE happen simultaneously
is very low.

Hidehiro Kawai (3):
panic: Change nmi_panic from macro to function
ipmi/watchdog: Use nmi_panic() when kernel panics in NMI handler
hpwdt: Use nmi_panic() when kernel panics in NMI handler


drivers/char/ipmi/ipmi_watchdog.c | 2 +-
drivers/watchdog/hpwdt.c | 11 +++++------
include/linux/kernel.h | 21 +--------------------
kernel/panic.c | 20 ++++++++++++++++++++
4 files changed, 27 insertions(+), 27 deletions(-)


--
Hidehiro Kawai
Hitachi, Ltd. Research & Development Group



2016-03-03 11:03:32

by Hidehiro Kawai

[permalink] [raw]
Subject: [v3 PATCH 3/3] hpwdt: Use nmi_panic() when kernel panics in NMI handler

commit 1717f2096b54 ("panic, x86: Fix re-entrance problem due to
panic on NMI") introduced nmi_panic() which prevents concurrent and
recursive execution of panic(). It also saves registers for the
crash dump on x86 by later commit 58c5661f2144 ("panic, x86: Allow
CPUs to save registers even if looping in NMI context").

hpwdt driver can call panic() from NMI handler, so replace it with
nmi_panic(). Also, do some cleanups.

Changes since V1:
- Use direct return instead of goto
- Combine the panic message string into a single line

Signed-off-by: Hidehiro Kawai <[email protected]>
Cc: Thomas Mingarelli <[email protected]>
Cc: Wim Van Sebroeck <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: [email protected]
---
drivers/watchdog/hpwdt.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
index 92443c3..a6c8797 100644
--- a/drivers/watchdog/hpwdt.c
+++ b/drivers/watchdog/hpwdt.c
@@ -483,7 +483,7 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
static int die_nmi_called;

if (!hpwdt_nmi_decoding)
- goto out;
+ return NMI_DONE;

spin_lock_irqsave(&rom_lock, rom_pl);
if (!die_nmi_called && !is_icru && !is_uefi)
@@ -496,11 +496,11 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)

if (!is_icru && !is_uefi) {
if (cmn_regs.u1.ral == 0) {
- panic("An NMI occurred, "
- "but unable to determine source.\n");
+ nmi_panic(regs, "An NMI occurred, but unable to determine source.\n");
+ return NMI_HANDLED;
}
}
- panic("An NMI occurred. Depending on your system the reason "
+ nmi_panic(regs, "An NMI occurred. Depending on your system the reason "
"for the NMI is logged in any one of the following "
"resources:\n"
"1. Integrated Management Log (IML)\n"
@@ -508,8 +508,7 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
"3. OA Forward Progress Log\n"
"4. iLO Event Log");

-out:
- return NMI_DONE;
+ return NMI_HANDLED;
}
#endif /* CONFIG_HPWDT_NMI_DECODING */



2016-03-03 11:03:58

by Hidehiro Kawai

[permalink] [raw]
Subject: [v3 PATCH 2/3] ipmi/watchdog: Use nmi_panic() when kernel panics in NMI handler

commit 1717f2096b54 ("panic, x86: Fix re-entrance problem due to
panic on NMI") introduced nmi_panic() which prevents concurrent and
recursive execution of panic(). It also saves registers for the
crash dump on x86 by later commit 58c5661f2144 ("panic, x86: Allow
CPUs to save registers even if looping in NMI context").

ipmi_watchdog driver can call panic() from NMI handler, so replace
it with nmi_panic().

Signed-off-by: Hidehiro Kawai <[email protected]>
Acked-by: Corey Minyard <[email protected]>
Acked-by: Guenter Roeck <[email protected]>
Reviewed-by: Michal Hocko <[email protected]>
Cc: [email protected]
---
drivers/char/ipmi/ipmi_watchdog.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
index 096f0ce..4facc75 100644
--- a/drivers/char/ipmi/ipmi_watchdog.c
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -1140,7 +1140,7 @@ ipmi_nmi(unsigned int val, struct pt_regs *regs)
the timer. So do so. */
pretimeout_since_last_heartbeat = 1;
if (atomic_inc_and_test(&preop_panic_excl))
- panic(PFX "pre-timeout");
+ nmi_panic(regs, PFX "pre-timeout");
}

return NMI_HANDLED;


2016-03-03 11:03:56

by Hidehiro Kawai

[permalink] [raw]
Subject: [v3 PATCH 1/3] panic: Change nmi_panic from macro to function

Change nmi_panic() macro to a normal function for the portability.
Also, export it for modules.

Changes since v2:
- Make nmi_panic receive a single string instead of printf style args

Signed-off-by: Hidehiro Kawai <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Michal Nazarewicz <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Nicolas Iooss <[email protected]>
Cc: Javi Merino <[email protected]>
Cc: Gobinda Charan Maji <[email protected]>
Cc: "Steven Rostedt (Red Hat)" <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vitaly Kuznetsov <[email protected]>
Cc: HATAYAMA Daisuke <[email protected]>
Cc: Tejun Heo <[email protected]>
---
include/linux/kernel.h | 21 +--------------------
kernel/panic.c | 20 ++++++++++++++++++++
2 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index f31638c..cbe7d70 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -255,7 +255,7 @@ extern long (*panic_blink)(int state);
__printf(1, 2)
void panic(const char *fmt, ...)
__noreturn __cold;
-void nmi_panic_self_stop(struct pt_regs *);
+void nmi_panic(struct pt_regs *regs, const char *msg);
extern void oops_enter(void);
extern void oops_exit(void);
void print_oops_end_marker(void);
@@ -455,25 +455,6 @@ extern atomic_t panic_cpu;
#define PANIC_CPU_INVALID -1

/*
- * A variant of panic() called from NMI context. We return if we've already
- * panicked on this CPU. If another CPU already panicked, loop in
- * nmi_panic_self_stop() which can provide architecture dependent code such
- * as saving register state for crash dump.
- */
-#define nmi_panic(regs, fmt, ...) \
-do { \
- int old_cpu, cpu; \
- \
- cpu = raw_smp_processor_id(); \
- old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu); \
- \
- if (old_cpu == PANIC_CPU_INVALID) \
- panic(fmt, ##__VA_ARGS__); \
- else if (old_cpu != cpu) \
- nmi_panic_self_stop(regs); \
-} while (0)
-
-/*
* Only to be used by arch init code. If the user over-wrote the default
* CONFIG_PANIC_TIMEOUT, honor it.
*/
diff --git a/kernel/panic.c b/kernel/panic.c
index d96469d..8abfc30 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -72,6 +72,26 @@ void __weak nmi_panic_self_stop(struct pt_regs *regs)

atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID);

+/*
+ * A variant of panic() called from NMI context. We return if we've already
+ * panicked on this CPU. If another CPU already panicked, loop in
+ * nmi_panic_self_stop() which can provide architecture dependent code such
+ * as saving register state for crash dump.
+ */
+void nmi_panic(struct pt_regs *regs, const char *msg)
+{
+ int old_cpu, cpu;
+
+ cpu = raw_smp_processor_id();
+ old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu);
+
+ if (old_cpu == PANIC_CPU_INVALID)
+ panic("%s", msg);
+ else if (old_cpu != cpu)
+ nmi_panic_self_stop(regs);
+}
+EXPORT_SYMBOL(nmi_panic);
+
/**
* panic - halt the system
* @fmt: The text string to print


2016-03-03 12:17:06

by Guenter Roeck

[permalink] [raw]
Subject: Re: [v3 PATCH 3/3] hpwdt: Use nmi_panic() when kernel panics in NMI handler

On 03/03/2016 02:57 AM, Hidehiro Kawai wrote:
> commit 1717f2096b54 ("panic, x86: Fix re-entrance problem due to
> panic on NMI") introduced nmi_panic() which prevents concurrent and
> recursive execution of panic(). It also saves registers for the
> crash dump on x86 by later commit 58c5661f2144 ("panic, x86: Allow
> CPUs to save registers even if looping in NMI context").
>
> hpwdt driver can call panic() from NMI handler, so replace it with
> nmi_panic(). Also, do some cleanups.
>
> Changes since V1:
> - Use direct return instead of goto
> - Combine the panic message string into a single line
>
> Signed-off-by: Hidehiro Kawai <[email protected]>
> Cc: Thomas Mingarelli <[email protected]>
> Cc: Wim Van Sebroeck <[email protected]>
> Cc: Guenter Roeck <[email protected]>

Acked-by: Guenter Roeck <[email protected]>

> Cc: [email protected]

In case you resend the series, please drop this Cc: from the commit logs.
Please see usage of Cc: in Documentation/SubmittingPatches.

Thanks,
Guenter

> ---
> drivers/watchdog/hpwdt.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
> index 92443c3..a6c8797 100644
> --- a/drivers/watchdog/hpwdt.c
> +++ b/drivers/watchdog/hpwdt.c
> @@ -483,7 +483,7 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
> static int die_nmi_called;
>
> if (!hpwdt_nmi_decoding)
> - goto out;
> + return NMI_DONE;
>
> spin_lock_irqsave(&rom_lock, rom_pl);
> if (!die_nmi_called && !is_icru && !is_uefi)
> @@ -496,11 +496,11 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
>
> if (!is_icru && !is_uefi) {
> if (cmn_regs.u1.ral == 0) {
> - panic("An NMI occurred, "
> - "but unable to determine source.\n");
> + nmi_panic(regs, "An NMI occurred, but unable to determine source.\n");
> + return NMI_HANDLED;
> }
> }
> - panic("An NMI occurred. Depending on your system the reason "
> + nmi_panic(regs, "An NMI occurred. Depending on your system the reason "
> "for the NMI is logged in any one of the following "
> "resources:\n"
> "1. Integrated Management Log (IML)\n"
> @@ -508,8 +508,7 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
> "3. OA Forward Progress Log\n"
> "4. iLO Event Log");
>
> -out:
> - return NMI_DONE;
> + return NMI_HANDLED;
> }
> #endif /* CONFIG_HPWDT_NMI_DECODING */
>
>
>
>

2016-03-03 13:15:09

by Borislav Petkov

[permalink] [raw]
Subject: Re: [v3 PATCH 1/3] panic: Change nmi_panic from macro to function

On Thu, Mar 03, 2016 at 07:57:44PM +0900, Hidehiro Kawai wrote:
> Change nmi_panic() macro to a normal function for the portability.

portability?

> Also, export it for modules.
>
> Changes since v2:
> - Make nmi_panic receive a single string instead of printf style args
>
> Signed-off-by: Hidehiro Kawai <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Cc: Borislav Petkov <[email protected]>
> Cc: Michal Nazarewicz <[email protected]>
> Cc: Michal Hocko <[email protected]>
> Cc: Rasmus Villemoes <[email protected]>
> Cc: Nicolas Iooss <[email protected]>
> Cc: Javi Merino <[email protected]>
> Cc: Gobinda Charan Maji <[email protected]>
> Cc: "Steven Rostedt (Red Hat)" <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Vitaly Kuznetsov <[email protected]>
> Cc: HATAYAMA Daisuke <[email protected]>
> Cc: Tejun Heo <[email protected]>
> ---
> include/linux/kernel.h | 21 +--------------------
> kernel/panic.c | 20 ++++++++++++++++++++
> 2 files changed, 21 insertions(+), 20 deletions(-)

Acked-by: Borislav Petkov <[email protected]>

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.

2016-03-04 17:49:07

by Michal Hocko

[permalink] [raw]
Subject: Re: [v3 PATCH 1/3] panic: Change nmi_panic from macro to function

On Thu 03-03-16 19:57:44, Hidehiro Kawai wrote:
> Change nmi_panic() macro to a normal function for the portability.
> Also, export it for modules.

I guess you wanted to say
"
Change nmi_panic() from macro to a normal function so that it can be
exported to modules. At least ipmi and hpwdt watchdogs can be compiled
as a module and need to panic from the NMI context.
"
>
> Changes since v2:
> - Make nmi_panic receive a single string instead of printf style args
>
> Signed-off-by: Hidehiro Kawai <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Cc: Borislav Petkov <[email protected]>
> Cc: Michal Nazarewicz <[email protected]>
> Cc: Michal Hocko <[email protected]>
> Cc: Rasmus Villemoes <[email protected]>
> Cc: Nicolas Iooss <[email protected]>
> Cc: Javi Merino <[email protected]>
> Cc: Gobinda Charan Maji <[email protected]>
> Cc: "Steven Rostedt (Red Hat)" <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Vitaly Kuznetsov <[email protected]>
> Cc: HATAYAMA Daisuke <[email protected]>
> Cc: Tejun Heo <[email protected]>

For the change itself
Acked-by: Michal Hocko <[email protected]>

> ---
> include/linux/kernel.h | 21 +--------------------
> kernel/panic.c | 20 ++++++++++++++++++++
> 2 files changed, 21 insertions(+), 20 deletions(-)
>
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index f31638c..cbe7d70 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -255,7 +255,7 @@ extern long (*panic_blink)(int state);
> __printf(1, 2)
> void panic(const char *fmt, ...)
> __noreturn __cold;
> -void nmi_panic_self_stop(struct pt_regs *);
> +void nmi_panic(struct pt_regs *regs, const char *msg);
> extern void oops_enter(void);
> extern void oops_exit(void);
> void print_oops_end_marker(void);
> @@ -455,25 +455,6 @@ extern atomic_t panic_cpu;
> #define PANIC_CPU_INVALID -1
>
> /*
> - * A variant of panic() called from NMI context. We return if we've already
> - * panicked on this CPU. If another CPU already panicked, loop in
> - * nmi_panic_self_stop() which can provide architecture dependent code such
> - * as saving register state for crash dump.
> - */
> -#define nmi_panic(regs, fmt, ...) \
> -do { \
> - int old_cpu, cpu; \
> - \
> - cpu = raw_smp_processor_id(); \
> - old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu); \
> - \
> - if (old_cpu == PANIC_CPU_INVALID) \
> - panic(fmt, ##__VA_ARGS__); \
> - else if (old_cpu != cpu) \
> - nmi_panic_self_stop(regs); \
> -} while (0)
> -
> -/*
> * Only to be used by arch init code. If the user over-wrote the default
> * CONFIG_PANIC_TIMEOUT, honor it.
> */
> diff --git a/kernel/panic.c b/kernel/panic.c
> index d96469d..8abfc30 100644
> --- a/kernel/panic.c
> +++ b/kernel/panic.c
> @@ -72,6 +72,26 @@ void __weak nmi_panic_self_stop(struct pt_regs *regs)
>
> atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID);
>
> +/*
> + * A variant of panic() called from NMI context. We return if we've already
> + * panicked on this CPU. If another CPU already panicked, loop in
> + * nmi_panic_self_stop() which can provide architecture dependent code such
> + * as saving register state for crash dump.
> + */
> +void nmi_panic(struct pt_regs *regs, const char *msg)
> +{
> + int old_cpu, cpu;
> +
> + cpu = raw_smp_processor_id();
> + old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu);
> +
> + if (old_cpu == PANIC_CPU_INVALID)
> + panic("%s", msg);
> + else if (old_cpu != cpu)
> + nmi_panic_self_stop(regs);
> +}
> +EXPORT_SYMBOL(nmi_panic);
> +
> /**
> * panic - halt the system
> * @fmt: The text string to print
>
>

--
Michal Hocko
SUSE Labs

2016-03-04 19:27:49

by Michal Nazarewicz

[permalink] [raw]
Subject: Re: [v3 PATCH 1/3] panic: Change nmi_panic from macro to function

On Thu, Mar 03 2016, Hidehiro Kawai wrote:
> Change nmi_panic() macro to a normal function for the portability.
> Also, export it for modules.
>
> Changes since v2:
> - Make nmi_panic receive a single string instead of printf style args
>
> Signed-off-by: Hidehiro Kawai <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Cc: Borislav Petkov <[email protected]>
> Cc: Michal Nazarewicz <[email protected]>

Code does what the commit advertises so

Acked-by: Michal Nazarewicz <[email protected]>

> Cc: Michal Hocko <[email protected]>
> Cc: Rasmus Villemoes <[email protected]>
> Cc: Nicolas Iooss <[email protected]>
> Cc: Javi Merino <[email protected]>
> Cc: Gobinda Charan Maji <[email protected]>
> Cc: "Steven Rostedt (Red Hat)" <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Vitaly Kuznetsov <[email protected]>
> Cc: HATAYAMA Daisuke <[email protected]>
> Cc: Tejun Heo <[email protected]>
> ---
> include/linux/kernel.h | 21 +-------------------
> kernel/panic.c | 20 ++++++++++++++++++++
> 2 files changed, 21 insertions(+), 20 deletions(-)
>
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index f31638c..cbe7d70 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -255,7 +255,7 @@ extern long (*panic_blink)(int state);
> __printf(1, 2)
> void panic(const char *fmt, ...)
> __noreturn __cold;
> -void nmi_panic_self_stop(struct pt_regs *);
> +void nmi_panic(struct pt_regs *regs, const char *msg);
> extern void oops_enter(void);
> extern void oops_exit(void);
> void print_oops_end_marker(void);
> @@ -455,25 +455,6 @@ extern atomic_t panic_cpu;
> #define PANIC_CPU_INVALID -1
>
> /*
> - * A variant of panic() called from NMI context. We return if we've already
> - * panicked on this CPU. If another CPU already panicked, loop in
> - * nmi_panic_self_stop() which can provide architecture dependent code such
> - * as saving register state for crash dump.
> - */
> -#define nmi_panic(regs, fmt, ...) \
> -do { \
> - int old_cpu, cpu; \
> - \
> - cpu = raw_smp_processor_id(); \
> - old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu); \
> - \
> - if (old_cpu == PANIC_CPU_INVALID) \
> - panic(fmt, ##__VA_ARGS__); \
> - else if (old_cpu != cpu) \
> - nmi_panic_self_stop(regs); \
> -} while (0)
> -
> -/*
> * Only to be used by arch init code. If the user over-wrote the default
> * CONFIG_PANIC_TIMEOUT, honor it.
> */
> diff --git a/kernel/panic.c b/kernel/panic.c
> index d96469d..8abfc30 100644
> --- a/kernel/panic.c
> +++ b/kernel/panic.c
> @@ -72,6 +72,26 @@ void __weak nmi_panic_self_stop(struct pt_regs *regs)
>
> atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID);
>
> +/*
> + * A variant of panic() called from NMI context. We return if we've already
> + * panicked on this CPU. If another CPU already panicked, loop in
> + * nmi_panic_self_stop() which can provide architecture dependent code such
> + * as saving register state for crash dump.
> + */
> +void nmi_panic(struct pt_regs *regs, const char *msg)
> +{
> + int old_cpu, cpu;
> +
> + cpu = raw_smp_processor_id();
> + old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu);
> +
> + if (old_cpu == PANIC_CPU_INVALID)
> + panic("%s", msg);
> + else if (old_cpu != cpu)
> + nmi_panic_self_stop(regs);
> +}
> +EXPORT_SYMBOL(nmi_panic);
> +
> /**
> * panic - halt the system
> * @fmt: The text string to print
>
>

--
Best regards
ミハウ “????????????????86” ナザレヴイツ
«If at first you don’t succeed, give up skydiving»

2016-03-07 10:54:10

by Hidehiro Kawai

[permalink] [raw]
Subject: RE: [v3 PATCH 1/3] panic: Change nmi_panic from macro to function

> From: Borislav Petkov [mailto:[email protected]]
> On Thu, Mar 03, 2016 at 07:57:44PM +0900, Hidehiro Kawai wrote:
> > Change nmi_panic() macro to a normal function for the portability.
>
> portability?

I wanted to say encapsulating things into a function makes modules
only have to know about the function. Modules don't need to know
all things in the macro. But I thought again, and `portability'
was not appropriate.

However, this patch set has been queued into -mm now. So I'll
leave this if not necessary.

Regards,
Hidehiro Kawai

> > Also, export it for modules.
> >
> > Changes since v2:
> > - Make nmi_panic receive a single string instead of printf style args
> >
> > Signed-off-by: Hidehiro Kawai <[email protected]>
> > Cc: Andrew Morton <[email protected]>
> > Cc: Borislav Petkov <[email protected]>
> > Cc: Michal Nazarewicz <[email protected]>
> > Cc: Michal Hocko <[email protected]>
> > Cc: Rasmus Villemoes <[email protected]>
> > Cc: Nicolas Iooss <[email protected]>
> > Cc: Javi Merino <[email protected]>
> > Cc: Gobinda Charan Maji <[email protected]>
> > Cc: "Steven Rostedt (Red Hat)" <[email protected]>
> > Cc: Thomas Gleixner <[email protected]>
> > Cc: Vitaly Kuznetsov <[email protected]>
> > Cc: HATAYAMA Daisuke <[email protected]>
> > Cc: Tejun Heo <[email protected]>
> > ---
> > include/linux/kernel.h | 21 +--------------------
> > kernel/panic.c | 20 ++++++++++++++++++++
> > 2 files changed, 21 insertions(+), 20 deletions(-)
>
> Acked-by: Borislav Petkov <[email protected]>
>
> --
> Regards/Gruss,
> Boris.
>
> ECO tip #101: Trim your mails when you reply.

2016-03-07 11:07:39

by Hidehiro Kawai

[permalink] [raw]
Subject: RE: [Openipmi-developer] [v3 PATCH 3/3] hpwdt: Use nmi_panic() when kernel panics in NMI handler

> From: Phil Pokorny [mailto:[email protected]]
>
> While you are in drivers/watchdog/hpwdt.c replacing panic() with
> nmi_panic() can you also fix a few more of the broken strings? The
> Linux style guide specfiically says NOT to break strings that are user
> visible because it breaks "grep". So:

Ahh, yes. I should have fixed this as well as the former case.
But this patch set has already been queued into -mm tree, so
I'll leave this patch if the fix is not important.

Regards,
Hidehiro Kawai

>
> - panic("An NMI occurred. Depending on your system the reason "
> + nmi_panic(regs, "An NMI occurred. Depending on your system the reason "
> "for the NMI is logged in any one of the following "
> "resources:\n"
> "1. Integrated Management Log (IML)\n"
>
> Should probably be:
>
> - panic("An NMI occurred. Depending on your system the reason "
> - "for the NMI is logged in any one of the following "
> - "resources:\n"
> + nmi_panic(regs, "An NMI occurred. Depending on your system the
> reason for the NMI is logged in any one of the following resources:\n"
> "1. Integrated Management Log (IML)\n"
>
> So it's okay to break on "\n", but not in the middle of a line.
>
> --
> Philip Pokorny, RHCE
> Chief Technology Officer
> PENGUIN COMPUTING, Inc
> http://www.penguincomputing.com
>
> Changing the world through technical innovation

2016-03-07 11:13:23

by Borislav Petkov

[permalink] [raw]
Subject: Re: [v3 PATCH 1/3] panic: Change nmi_panic from macro to function

On Mon, Mar 07, 2016 at 10:53:51AM +0000, 河合英宏 / KAWAI,HIDEHIRO wrote:
> > From: Borislav Petkov [mailto:[email protected]]
> > On Thu, Mar 03, 2016 at 07:57:44PM +0900, Hidehiro Kawai wrote:
> > > Change nmi_panic() macro to a normal function for the portability.
> >
> > portability?
>
> I wanted to say encapsulating things into a function makes modules
> only have to know about the function. Modules don't need to know
> all things in the macro. But I thought again, and `portability'
> was not appropriate.
>
> However, this patch set has been queued into -mm now. So I'll
> leave this if not necessary.

Unless Andrew is willing to do a quick "quilt header -e" on your patch
and paste in a corrected commit message text which you give him...

:-)

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.