From: catalin.marinas@arm.com (Catalin Marinas) Date: Fri, 4 Jul 2014 16:45:23 +0100 Subject: [PATCH v2 2/2] efi/arm64: preserve FP/SIMD registers on UEFI runtime services calls In-Reply-To: <1403777346-28629-3-git-send-email-ard.biesheuvel@linaro.org> References: <1403777346-28629-1-git-send-email-ard.biesheuvel@linaro.org> <1403777346-28629-3-git-send-email-ard.biesheuvel@linaro.org> Message-ID: <20140704154522.GJ16404@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Jun 26, 2014 at 11:09:06AM +0100, Ard Biesheuvel wrote: > According to the UEFI spec section 2.3.6.4, the use of FP/SIMD instructions is > allowed, and should adhere to the AAPCS64 calling convention, which states that > 'only the bottom 64 bits of each value stored in registers v8-v15 need to be > preserved' (section 5.1.2). > > This applies equally to UEFI Runtime Services called by the kernel, so make sure > the FP/SIMD register file is preserved in this case. > > Signed-off-by: Ard Biesheuvel While the code looks fine, I think there is a mismatch between what the subject says and what the patch does (enabling EFI_RUNTIME_WRAPPERS). -- Catalin