[PATCH] x86/entry: Remove put_ret_addr_in_rdi THUNK macro argument

From: Borislav Petkov
Date: Thu Jan 14 2021 - 08:28:58 EST


On Thu, Jan 14, 2021 at 12:36:45PM +0100, Peter Zijlstra wrote:
> And while looking, I suppose we can delete the put_ret_addr_in_rdi crud,
> but that's another patch.

---
From: Borislav Petkov <bp@xxxxxxx>
Date: Thu, 14 Jan 2021 14:25:35 +0100
Subject: [PATCH] x86/entry: Remove put_ret_addr_in_rdi THUNK macro argument

That logic is unused since

320100a5ffe5 ("x86/entry: Remove the TRACE_IRQS cruft")

Remove it.

Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/entry/thunk_64.S | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/arch/x86/entry/thunk_64.S b/arch/x86/entry/thunk_64.S
index c9a9fbf1655f..496b11ec469d 100644
--- a/arch/x86/entry/thunk_64.S
+++ b/arch/x86/entry/thunk_64.S
@@ -10,7 +10,7 @@
#include <asm/export.h>

/* rdi: arg1 ... normal C conventions. rax is saved/restored. */
- .macro THUNK name, func, put_ret_addr_in_rdi=0
+ .macro THUNK name, func
SYM_FUNC_START_NOALIGN(\name)
pushq %rbp
movq %rsp, %rbp
@@ -25,11 +25,6 @@ SYM_FUNC_START_NOALIGN(\name)
pushq %r10
pushq %r11

- .if \put_ret_addr_in_rdi
- /* 8(%rbp) is return addr on stack */
- movq 8(%rbp), %rdi
- .endif
-
call \func
jmp __thunk_restore
SYM_FUNC_END(\name)
--
2.29.2

--
Regards/Gruss,
Boris.

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