From 7e611e7dbb235938fca1dd359bad5e5f86ceabcb Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 8 Mar 2018 08:00:13 +0000 Subject: efi/arm64: Check whether x18 is preserved by runtime services calls Whether or not we will ever decide to start using x18 as a platform register in Linux is uncertain, but by that time, we will need to ensure that UEFI runtime services calls don't corrupt it. So let's start issuing warnings now for this, and increase the likelihood that these firmware images have all been replaced by that time. This has been fixed on the EDK2 side in commit: 6d73863b5464 ("BaseTools/tools_def AARCH64: mark register x18 as reserved") dated July 13, 2017. Signed-off-by: Ard Biesheuvel Acked-by: Will Deacon Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180308080020.22828-6-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- arch/arm64/include/asm/efi.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch/arm64/include/asm/efi.h') diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h index 8389050328bb..192d791f1103 100644 --- a/arch/arm64/include/asm/efi.h +++ b/arch/arm64/include/asm/efi.h @@ -31,7 +31,7 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); ({ \ efi_##f##_t *__f; \ __f = p->f; \ - __f(args); \ + __efi_rt_asm_wrapper(__f, #f, args); \ }) #define arch_efi_call_virt_teardown() \ @@ -40,6 +40,8 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); efi_virtmap_unload(); \ }) +efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...); + #define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT) /* arch specific definitions used by the stub code */ -- cgit v1.2.3