https://github.com/torvalds/linux
Revision cab8bd3410d448279e3bd0fbf96d31db0bf770fa authored by Hidetoshi Seto on 29 July 2009, 22:04:14 UTC, committed by Linus Torvalds on 30 July 2009, 02:10:36 UTC
commit d6580a9f15238b87e618310c862231ae3f352d2d ("kexec: sysrq: simplify sysrq-c handler") changed the behavior of sysrq-c to unconditional dereference of NULL pointer. So in cases with CONFIG_KEXEC, where crash_kexec() was directly called from sysrq-c before, now it can be said that a step of "real oops" was inserted before starting kdump. However, in contrast to oops via SysRq-c from keyboard which results in panic due to in_interrupt(), oops via "echo c > /proc/sysrq-trigger" will not become panic unless panic_on_oops=1. It means that even if dump is properly configured to be taken on panic, the sysrq-c from proc interface might not start crashdump while the sysrq-c from keyboard can start crashdump. This confuses traditional users of kdump, i.e. people who expect sysrq-c to do common behavior in both of the keyboard and proc interface. This patch brings the keyboard and proc interface behavior of sysrq-c in line, by forcing panic_on_oops=1 before oops in sysrq-c handler. And some updates in documentation are included, to clarify that there is no longer dependency with CONFIG_KEXEC, and that now the system can just crash by sysrq-c if no dump mechanism is configured. Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: Brayan Arraes <brayan@yack.com.br> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Tip revision: cab8bd3410d448279e3bd0fbf96d31db0bf770fa authored by Hidetoshi Seto on 29 July 2009, 22:04:14 UTC
sysrq, kdump: make sysrq-c consistent
sysrq, kdump: make sysrq-c consistent
Tip revision: cab8bd3
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arch | ||
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crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.gitignore | -rw-r--r-- | 952 bytes |
.mailmap | -rw-r--r-- | 3.9 KB |
COPYING | -rw-r--r-- | 18.3 KB |
CREDITS | -rw-r--r-- | 91.7 KB |
Kbuild | -rw-r--r-- | 2.4 KB |
MAINTAINERS | -rw-r--r-- | 149.3 KB |
Makefile | -rw-r--r-- | 53.9 KB |
README | -rw-r--r-- | 17.0 KB |
REPORTING-BUGS | -rw-r--r-- | 3.1 KB |
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