linux/include
Frederic Weisbecker 44234adcdc hw-breakpoints: Modify breakpoints without unregistering them
Currently, when ptrace needs to modify a breakpoint, like disabling
it, changing its address, type or len, it calls
modify_user_hw_breakpoint(). This latter will perform the heavy and
racy task of unregistering the old breakpoint and registering a new
one.

This is racy as someone else might steal the reserved breakpoint
slot under us, which is undesired as the breakpoint is only
supposed to be modified, sometimes in the middle of a debugging
workflow. We don't want our slot to be stolen in the middle.

So instead of unregistering/registering the breakpoint, just
disable it while we modify its breakpoint fields and re-enable it
after if necessary.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1260347148-5519-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 09:48:20 +01:00
..
acpi ACPI: remove acpi_device_uid() and related stuff 2009-09-25 15:09:49 -04:00
asm-generic alpha: fix F_SETOWN_EX and F_GETLK64 conflict 2009-11-12 07:25:56 -08:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2009-09-11 09:38:37 -07:00
drm Merge branch 'drm-next' of ../drm-next into drm-linus 2009-10-08 14:03:05 +10:00
keys RxRPC: Use uX/sX rather than uintX_t/intX_t types 2009-09-16 00:01:13 -07:00
linux hw-breakpoints: Modify breakpoints without unregistering them 2009-12-09 09:48:20 +01:00
math-emu
media V4L/DVB (13019): video: initial support for ADV7180 2009-09-19 00:53:39 -03:00
mtd
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2009-11-09 09:51:42 -08:00
pcmcia PM / yenta: Split resume into early and late parts (rev. 4) 2009-11-03 10:54:58 +01:00
rdma trivial: fix typo "to to" in multiple files 2009-09-21 15:14:55 +02:00
rxrpc
scsi [SCSI] libiscsi: iscsi_session_setup to allow for private space 2009-10-02 14:01:39 -05:00
sound Merge branch 'topic/ymfpci' into for-linus 2009-09-10 15:33:09 +02:00
trace Merge branch 'perf/mce' into perf/core 2009-12-03 20:11:06 +01:00
video davinci-fb-frame-buffer-driver-for-ti-da8xx-omap-l1xx-v4 2009-09-23 07:39:51 -07:00
xen
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