On Mon, Jan 25, 2021 at 6:34 AM Greg KH [off-list ref] wrote:

On Mon, Jan 25, 2021 at 01:24:25PM +0000, Will Deacon wrote:

quoted

commit dca5244d2f5b94f1809f0c02a549edf41ccd5493 upstream.

GCC versions >= 4.9 and < 5.1 have been shown to emit memory references
beyond the stack pointer, resulting in memory corruption if an interrupt
is taken after the stack pointer has been adjusted but before the
reference has been executed. This leads to subtle, infrequent data
corruption such as the EXT4 problems reported by Russell King at the
link below.

Life is too short for buggy compilers, so raise the minimum GCC version
required by arm64 to 5.1.

Reported-by: Russell King <linux@armlinux.org.uk>
Suggested-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Tested-by: Nathan Chancellor <redacted>
Reviewed-by: Nick Desaulniers <redacted>
Reviewed-by: Nathan Chancellor <redacted>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <redacted> # 4.4.y, 4.9.y and 4.14.y only
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Florian Weimer <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nick Desaulniers <redacted>
Cc: Nathan Chancellor <redacted>
Cc: Naresh Kamboju <redacted>
Link: https://lore.kernel.org/r/20210105154726.GD1551@shell.armlinux.org.uk (local)
Link: https://lore.kernel.org/r/20210112224832.10980-1-will@kernel.org (local)
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
[will: backport to 4.4.y/4.9.y/4.14.y; add __clang__ check]

LGTM

quoted

Link: https://lore.kernel.org/r/CA+G9fYuzE9WMSB7uGjV4gTzK510SHEdJb_UXQCzsQ5MqA=h9SA@mail.gmail.com (local)
Signed-off-by: Will Deacon <will@kernel.org>
---
 include/linux/compiler-gcc.h | 6 ++++++
 1 file changed, 6 insertions(+)

Thanks, now queued up, let's try this again :)

greg k-h

-- 
Thanks,
~Nick Desaulniers