tree 8177015c7fe37b05df24165195a4027508ac4d7f
parent 25ce1dd71b8326f2542cf030f68e0e64c3d94dc1
author Nicolas Pitre <nico@cam.org> 1197665761 -0500
committer Russell King <rmk+kernel@arm.linux.org.uk> 1201361117 +0000

ARM kprobes: don't let a single-stepped stmdb corrupt the exception stack

If kprobes installs a breakpoint on a "stmdb sp!, {...}" instruction,
and then single-step it by simulation from the exception context, it will
corrupt the saved regs on the stack from the previous context.

To avoid this, let's add an optional parameter to the svc_entry macro
allowing for a hole to be created on the stack before saving the
interrupted context, and use it in the undef_svc handler when kprobes
is enabled.

Signed-off-by: Nicolas Pitre <nico@marvell.com>