On 01/17/22 at 11:33am, Baoquan He wrote:
> On 01/14/22 at 03:30pm, Guilherme G. Piccoli wrote:
> ......
> > .../admin-guide/kernel-parameters.txt | 4 ++++
> > kernel/panic.c | 22 ++++++++++++++-----
> > 2 files changed, 21 insertions(+), 5 deletions(-)
> >
> > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> > index a069d8fe2fee..0f5cbe141bfd 100644
> > --- a/Documentation/admin-guide/kernel-parameters.txt
> > +++ b/Documentation/admin-guide/kernel-parameters.txt
> > @@ -3727,6 +3727,10 @@
> > bit 4: print ftrace buffer
> > bit 5: print all printk messages in buffer
> > bit 6: print all CPUs backtrace (if available in the arch)
> > + *Be aware* that this option may print a _lot_ of lines,
> > + so there are risks of losing older messages in the log.
> > + Use this option carefully, maybe worth to setup a
> > + bigger log buffer with "log_buf_len" along with this.
> >
> > panic_on_taint= Bitmask for conditionally calling panic() in add_taint()
> > Format: <hex>[,nousertaint]
> > diff --git a/kernel/panic.c b/kernel/panic.c
> > index 41ecf9ab824a..4ae712665f75 100644
> > --- a/kernel/panic.c
> > +++ b/kernel/panic.c
> > @@ -148,10 +148,13 @@ void nmi_panic(struct pt_regs *regs, const char *msg)
> > }
> > EXPORT_SYMBOL(nmi_panic);
> >
> > -static void panic_print_sys_info(void)
> > +static void panic_print_sys_info(bool after_kmsg_dumpers)
> > {
> > - if (panic_print & PANIC_PRINT_ALL_PRINTK_MSG)
> > - console_flush_on_panic(CONSOLE_REPLAY_ALL);
> > + if (after_kmsg_dumpers) {
> > + if (panic_print & PANIC_PRINT_ALL_PRINTK_MSG)
> > + console_flush_on_panic(CONSOLE_REPLAY_ALL);
> > + return;
> > + }
> >
> > if (panic_print & PANIC_PRINT_ALL_CPU_BT)
> > trigger_all_cpu_backtrace();
> > @@ -249,7 +252,7 @@ void panic(const char *fmt, ...)
> > * show some extra information on kernel log if it was set...
> > */
> > if (kexec_crash_loaded())
> > - panic_print_sys_info();
> > + panic_print_sys_info(false);
>
> Patch can'e be applied on the latest code of linus's tree, can you tell
> which branch your code are based on?
OK, this is based on linux-next, I will apply this patch on the
linux-next/master and have a look.
>
> >
> > /*
> > * If we have crashed and we have a crash kernel loaded let it handle
> > @@ -283,6 +286,15 @@ void panic(const char *fmt, ...)
> > */
> > atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
> >
> > + /*
> > + * If kexec_crash_loaded() is true and we still reach this point,
> > + * kernel would double print the information from panic_print; so
> > + * let's guard against that possibility (it happens if kdump users
> > + * also set crash_kexec_post_notifiers in the command-line).
> > + */
> > + if (!kexec_crash_loaded())
> > + panic_print_sys_info(false);
> > +
> > kmsg_dump(KMSG_DUMP_PANIC);
> >
> > /*
> > @@ -313,7 +325,7 @@ void panic(const char *fmt, ...)
> > debug_locks_off();
> > console_flush_on_panic(CONSOLE_FLUSH_PENDING);
> >
> > - panic_print_sys_info();
> > + panic_print_sys_info(true);
> >
> > if (!panic_blink)
> > panic_blink = no_blink;
> > --
> > 2.34.1
> >
>
_______________________________________________
kexec mailing list
kexec@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/kexec
