| Message ID | 1396543508-12280-2-git-send-email-peter.maydell@linaro.org |
|---|---|
| State | New |
| Headers | show |
On 04/03/2014 09:45 AM, Peter Maydell wrote: > From: Andrei Warkentin <andrey.warkentin@gmail.com> > > When checking a page range, if we found that a page was > made read-only by QEMU because it contained translated code, > we were incorrectly returning immediately after unprotecting > that page, rather than continuing to check the entire range, > so we might fail to unprotect pages later in the range, or > might incorrectly return a "success" result even if later > pages were not writable. > > In particular, this could cause segfaults in a case where > signals are delivered back to back on a target architecture > which uses trampoline code in the stack frame (as AArch64 > currently does). The second signal causes a segfault because > the frame cannot be written to (it was protected because > we translated and executed the restorer trampoline, and the > unprotect logic did not unprotect the whole range). > > Signed-off-by: Andrei Warkentin <andrey.warkentin@gmail.com > [PMM: expanded commit message a bit] > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > translate-all.c | 1 - > 1 file changed, 1 deletion(-) Reviewed-by: Richard Henderson <rth@twiddle.net> r~
diff --git a/translate-all.c b/translate-all.c index f243c10..5759974 100644 --- a/translate-all.c +++ b/translate-all.c @@ -1777,7 +1777,6 @@ int page_check_range(target_ulong start, target_ulong len, int flags) return -1; } } - return 0; } } return 0;