Commit-ID: bea23c757f66d91dac8fdadd94da0cba6b0b66bc Gitweb: http://git.kernel.org/tip/bea23c757f66d91dac8fdadd94da0cba6b0b66bc Author: Alex Thorlton <athorlton@xxxxxxx> AuthorDate: Fri, 13 May 2016 21:34:42 +0100 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Mon, 16 May 2016 12:38:06 +0200 x86/efi: Fix 7th argument to efi_call() The efi_call() assembly code has a slight error that prevents us from using arguments 7 and higher, which will be passed in on the stack: mov (%rsp), %rax mov 8(%rax), %rax ... mov %rax, 40(%rsp) This code goes and grabs the return address for the current stack frame, and puts it on the stack, next to the 5th argument for the EFI runtime call. Considering the fact that having the return address in that position on the stack makes no sense, I'm guessing that the intent of this code was actually to grab an argument off the stack frame for this call and place it into the frame for the next one. The small change to that offset (i.e. 8(%rax) to 16(%rax)) ensures that we grab the 7th argument off the stack, and pass it as the 6th argument to the EFI runtime function that we're about to call. This change gets our EFI runtime calls that need to pass more than 6 arguments working again. SGI/UV is the only platform that passes more than 6 arguments. Signed-off-by: Alex Thorlton <athorlton@xxxxxxx> [ Updated changelog. ] Signed-off-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: Dimitri Sivanich <sivanich@xxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Mike Travis <travis@xxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Russ Anderson <rja@xxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Vince Weaver <vincent.weaver@xxxxxxxxx> Cc: linux-efi@xxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/1463171682-13881-2-git-send-email-matt@xxxxxxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/platform/efi/efi_stub_64.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/platform/efi/efi_stub_64.S b/arch/x86/platform/efi/efi_stub_64.S index 92723ae..62938ff 100644 --- a/arch/x86/platform/efi/efi_stub_64.S +++ b/arch/x86/platform/efi/efi_stub_64.S @@ -43,7 +43,7 @@ ENTRY(efi_call) FRAME_BEGIN SAVE_XMM mov (%rsp), %rax - mov 8(%rax), %rax + mov 16(%rax), %rax subq $48, %rsp mov %r9, 32(%rsp) mov %rax, 40(%rsp) -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html