[PATCH] arm64/fpsimd: Avoid unnecessary per-CPU buffers for EFI runtime calls

[Will Deacon]

On Tue, 18 Mar 2025 14:24:22 +0100, Ard Biesheuvel wrote:
> The EFI specification has some elaborate rules about which runtime
> services may be called while another runtime service call is already in
> progress. In Linux, however, for simplicity, all EFI runtime service
> invocations are serialized via the efi_runtime_lock semaphore.
> 
> This implies that calls to the helper pair arch_efi_call_virt_setup()
> and arch_efi_call_virt_teardown() are serialized too, and are guaranteed
> not to nest.  Furthermore, the arm64 arch code has its own spinlock to
> serialize use of the EFI runtime stack, of which only a single instance
> exists.
> 
> [...]

Applied to arm64 (for-next/efi), thanks!

[1/1] arm64/fpsimd: Avoid unnecessary per-CPU buffers for EFI runtime calls
      https://git.kernel.org/arm64/c/e04796c8b598

Cheers,
-- 
Will

https://fixes.arm64.dev
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