pm24.git/kernel/panic.c, branch v3.4-rc2

panic: don't print redundant backtraces on oops

2012-01-13T04:13:11Z

When an oops causes a panic and panic prints another backtrace it's pretty common to have the original oops data be scrolled away on a 80x50 screen. The second backtrace is quite redundant and not needed anyways. So don't print the panic backtrace when oops_in_progress is true. [akpm@linux-foundation.org: add comment] Signed-off-by: Andi Kleen Cc: Michael Holzheu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kdump: fix crash_kexec()/smp_send_stop() race in panic()

2012-01-13T04:13:11Z

When two CPUs call panic at the same time there is a possible race condition that can stop kdump. The first CPU calls crash_kexec() and the second CPU calls smp_send_stop() in panic() before crash_kexec() finished on the first CPU. So the second CPU stops the first CPU and therefore kdump fails: 1st CPU: panic()->crash_kexec()->mutex_trylock(&kexec_mutex)-> do kdump 2nd CPU: panic()->crash_kexec()->kexec_mutex already held by 1st CPU ->smp_send_stop()-> stop 1st CPU (stop kdump) This patch fixes the problem by introducing a spinlock in panic that allows only one CPU to process crash_kexec() and the subsequent panic code. All other CPUs call the weak function panic_smp_self_stop() that stops the CPU itself. This function can be overloaded by architecture code. For example "tile" can use their lower-power "nap" instruction for that. Signed-off-by: Michael Holzheu Acked-by: Chris Metcalf Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

treewide: remove useless NORET_TYPE macro and uses

2012-01-13T04:13:03Z

It's a very old and now unused prototype marking so just delete it. Neaten panic pointer argument style to keep checkpatch quiet. Signed-off-by: Joe Perches Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Haavard Skinnemoen Cc: Hans-Christian Egtvedt Cc: Tony Luck Cc: Fenghua Yu Acked-by: Geert Uytterhoeven Acked-by: Ralf Baechle Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Chris Metcalf Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lockdep, bug: Exclude TAINT_OOT_MODULE from disabling lock debugging

2011-12-07T22:32:10Z

We do want to allow lock debugging for GPL-compatible modules that are not (yet) built in-tree. This was disabled as a side-effect of commit 2449b8ba0745327c5fa49a8d9acffe03b2eded69 ('module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree'). Lock debug warnings now include taint flags, so kernel developers should still be able to deflect warnings caused by out-of-tree modules. The TAINT_PROPRIETARY_MODULE flag for non-GPL-compatible modules will still disable lock debugging. Signed-off-by: Ben Hutchings Cc: Nick Bowler Cc: Greg KH Cc: Dave Jones Cc: Rusty Russell Cc: Randy Dunlap Cc: Debian kernel maintainers Cc: Peter Zijlstra Cc: Alan Cox Link: http://lkml.kernel.org/r/1323268258.18450.11.camel@deadeye Signed-off-by: Ingo Molnar

lockdep, bug: Exclude TAINT_FIRMWARE_WORKAROUND from disabling lockdep

2011-12-06T07:16:47Z

It's unlikely that TAINT_FIRMWARE_WORKAROUND causes false lockdep messages, so do not disable lockdep in that case. We still want to keep lockdep disabled in the TAINT_OOT_MODULE case: - bin-only modules can cause various instabilities in their and in unrelated kernel code - they are impossible to debug for kernel developers - they also typically do not have the copyright license permission to link to the GPL-ed lockdep code. Suggested-by: Ben Hutchings Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-xopopjjens57r0i13qnyh2yo@git.kernel.org Signed-off-by: Ingo Molnar

module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree

2011-11-06T21:24:42Z

Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings Reviewed-by: Dave Jones Acked-by: Greg Kroah-Hartman Signed-off-by: Rusty Russell (patched oops-tracing.txt)

panic: panic=-1 for immediate reboot

2011-07-26T23:49:45Z

When a kernel BUG or oops occurs, ChromeOS intends to panic and immediately reboot, with stacktrace and other messages preserved in RAM across reboot. But the longer we delay, the more likely the user is to poweroff and lose the info. panic_timeout (seconds before rebooting) is set by panic= boot option or sysctl or /proc/sys/kernel/panic; but 0 means wait forever, so at present we have to delay at least 1 second. Let a negative number mean reboot immediately (with the small cosmetic benefit of suppressing that newline-less "Rebooting in %d seconds.." message). Signed-off-by: Hugh Dickins Signed-off-by: Mandeep Singh Baines Cc: Huang Ying Cc: Andi Kleen Cc: Hugh Dickins Cc: Olaf Hering Cc: Jesse Barnes Cc: Dave Airlie Cc: Greg Kroah-Hartman Cc: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

move x86 specific oops=panic to generic code

2011-03-23T00:44:11Z

The oops=panic cmdline option is not x86 specific, move it to generic code. Update documentation. Signed-off-by: Olaf Hering Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ACPI, APEI, Generic Hardware Error Source POLL/IRQ/NMI notification type support

2011-01-12T08:06:19Z

Generic Hardware Error Source provides a way to report platform hardware errors (such as that from chipset). It works in so called "Firmware First" mode, that is, hardware errors are reported to firmware firstly, then reported to Linux by firmware. This way, some non-standard hardware error registers or non-standard hardware link can be checked by firmware to produce more valuable hardware error information for Linux. This patch adds POLL/IRQ/NMI notification types support. Because the memory area used to transfer hardware error information from BIOS to Linux can be determined only in NMI, IRQ or timer handler, but general ioremap can not be used in atomic context, so a special version of atomic ioremap is implemented for that. Known issue: - Error information can not be printed for recoverable errors notified via NMI, because printk is not NMI-safe. Will fix this via delay printing to IRQ context via irq_work or make printk NMI-safe. v2: - adjust printk format per comments. Signed-off-by: Huang Ying Reviewed-by: Andi Kleen Signed-off-by: Len Brown

lib/bug.c: add oops end marker to WARN implementation

2010-08-11T15:59:22Z

We are missing the oops end marker for the exception based WARN implementation in lib/bug.c. This is useful for logfile analysis tools. Signed-off-by: Anton Blanchard Cc: Ingo Molnar Cc: Arjan van de Ven Cc: "Kirill A. Shutemov" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds