arm64/signal: Raise limit on stack frames
authorMark Brown <broonie@kernel.org>
Wed, 17 Aug 2022 18:23:21 +0000 (19:23 +0100)
committerWill Deacon <will@kernel.org>
Tue, 23 Aug 2022 10:29:11 +0000 (11:29 +0100)
commit7ddcaf78e93c9282b4d92184f511b4d5bee75355
treebbeaf1788951f79b75de5ce08db3c7a4ea808b15
parent53d2d84a1f6d68e036adab71df8e0f37cd2724f6
arm64/signal: Raise limit on stack frames

The signal code has a limit of 64K on the size of a stack frame that it
will generate, if this limit is exceeded then a process will be killed if
it receives a signal. Unfortunately with the advent of SME this limit is
too small - the maximum possible size of the ZA register alone is 64K. This
is not an issue for practical systems at present but is easily seen using
virtual platforms.

Raise the limit to 256K, this is substantially more than could be used by
any current architecture extension.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220817182324.638214-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
arch/arm64/kernel/signal.c