tree ec25f24103f10a6a620682fc9e1ab0849c7b4dce
parent c28f896634f2c931a298490deab3861ab117716a
author Prasanna S Panchamukhi <prasanna@in.ibm.com> 1143365904 -0800
committer Linus Torvalds <torvalds@g5.osdl.org> 1143392224 -0800

[PATCH] kprobes: fix broken fault handling for powerpc64

Provide proper kprobes fault handling, if a user-specified pre/post handlers
tries to access user address space, through copy_from_user(), get_user() etc.

The user-specified fault handler gets called only if the fault occurs while
executing user-specified handlers.  In such a case user-specified handler is
allowed to fix it first, later if the user-specifed fault handler does not fix
it, we try to fix it by calling fix_exception().

The user-specified handler will not be called if the fault happens when single
stepping the original instruction, instead we reset the current probe and
allow the system page fault handler to fix it up.

Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>