tree 4297d5647ce5e6cbe429dc506007579952c31015
parent 74f9c9c258249fba3e2e78f70691528426a6c010
author Hugh Dickins <hugh@veritas.com> 1122955902 -0700
committer Linus Torvalds <torvalds@g5.osdl.org> 1122957480 -0700

[PATCH] x86_64: access of some bad address

x86_64 has a large sparse gate area between VSYSCALL_START and
VSYSCALL_END, not all of it presently backed by pmds.  Alexander Nyberg has
found that in some circumstances gdb may try to ptrace here, and hit
get_user_pages BUG_ON.  It seems odd that gdb should be accessing here, but
it certainly shouldn't crash in this way: relax BUG_ON to -EFAULT.  Fixes
kernel bugzilla #4801.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>