Re: [PATCH AUTOSEL 5.18 063/159] arm64/sme: Add ID_AA64SMFR0_EL1 to __read_sysreg_by_encoding()

On Mon, May 30, 2022 at 04:17:19PM +0200, Mark Brown wrote:

On Mon, May 30, 2022 at 09:22:48AM -0400, Sasha Levin wrote:

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From: Mark Brown broonie@kernel.org

[ Upstream commit 8a58bcd00e2e8d46afce468adc09fcd7968f514c ]

We need to explicitly enumerate all the ID registers which we rely on for CPU capabilities in __read_sysreg_by_encoding(), ID_AA64SMFR0_EL1 was missed from this list so we trip a BUG() in paths which rely on that function such as CPU hotplug. Add the register.

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• read_sysreg_case(SYS_ID_AA64SMFR0_EL1);

This won't build on v5.18 since it does not contain SME support and therefore lacks the definition for the SME feature register.

Dropped, thanks!