| commit | eb3a72921c8276bf2cd028a458bb83435f16c91c | |
| author | Keshavamurthy Anil S <anil.s.keshavamurthy@intel.com> | |
| Wed, 11 Jan 2006 20:17:42 +0000 (11 12:17 -0800) | ||
| committer | Linus Torvalds <torvalds@g5.osdl.org> | |
| Thu, 12 Jan 2006 02:42:12 +0000 (11 18:42 -0800) | ||
| tree | 634eff43e1926bdb400d038eb08115193b6a7506 | treesnapshot (tar.gz zip) |
| parent | df019b1d8b893d0f0ee5a9b0f71486f0892561ae | commitdiff |
[PATCH] kprobes: fix race in recovery of reentrant probe
There is a window where a probe gets removed right after the probe is hit
on some different cpu. In this case probe handlers can't find a matching
probe instance related to break address. In this case we need to read the
original instruction at break address to see if that is not a break/int3
instruction and recover safely.
Previous code had a bug where we were not checking for the above race in
case of reentrant probes and the below patch fixes this race.
Tested on IA64, Powerpc, x86_64.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is a window where a probe gets removed right after the probe is hit
on some different cpu. In this case probe handlers can't find a matching
probe instance related to break address. In this case we need to read the
original instruction at break address to see if that is not a break/int3
instruction and recover safely.
Previous code had a bug where we were not checking for the above race in
case of reentrant probes and the below patch fixes this race.
Tested on IA64, Powerpc, x86_64.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>