diff options
| author | Jason Wessel <jason.wessel@windriver.com> | 2012-03-23 09:35:05 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-04-13 09:13:54 -0700 |
| commit | c9f568f1a99794aa7b749828c41fb7cdf55fe435 (patch) | |
| tree | 26050d4e3ef2e802c5855b6ca32635daef64c441 /include | |
| parent | 3c608af0c2643a9f17fef2f1cfa2a43a97bdf8a4 (diff) | |
x86,kgdb: Fix DEBUG_RODATA limitation using text_poke()
commit 3751d3e85cf693e10e2c47c03c8caa65e171099b upstream.
There has long been a limitation using software breakpoints with a
kernel compiled with CONFIG_DEBUG_RODATA going back to 2.6.26. For
this particular patch, it will apply cleanly and has been tested all
the way back to 2.6.36.
The kprobes code uses the text_poke() function which accommodates
writing a breakpoint into a read-only page. The x86 kgdb code can
solve the problem similarly by overriding the default breakpoint
set/remove routines and using text_poke() directly.
The x86 kgdb code will first attempt to use the traditional
probe_kernel_write(), and next try using a the text_poke() function.
The break point install method is tracked such that the correct break
point removal routine will get called later on.
Cc: x86@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Inspried-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/kgdb.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h index e5d689c1d77..c4d2fc194ed 100644 --- a/include/linux/kgdb.h +++ b/include/linux/kgdb.h @@ -63,7 +63,8 @@ enum kgdb_bptype { BP_HARDWARE_BREAKPOINT, BP_WRITE_WATCHPOINT, BP_READ_WATCHPOINT, - BP_ACCESS_WATCHPOINT + BP_ACCESS_WATCHPOINT, + BP_POKE_BREAKPOINT, }; enum kgdb_bpstate { |