[tip: x86/entry] x86/entry/fred: Encode frame pointer on entry

From: tip-bot2 for David Stevens

Date: Tue Jul 14 2026 - 19:09:25 EST


The following commit has been merged into the x86/entry branch of tip:

Commit-ID: dab01c597f6bd40e0efe7da967b8374ca1971b79
Gitweb: https://git.kernel.org/tip/dab01c597f6bd40e0efe7da967b8374ca1971b79
Author: David Stevens <stevensd@xxxxxxxxxx>
AuthorDate: Fri, 24 Apr 2026 12:14:54 -07:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Tue, 14 Jul 2026 11:08:12 -07:00

x86/entry/fred: Encode frame pointer on entry

Add missing ENCODE_FRAME_POINTER macro invocation into FRED_ENTER macro,
to prevent the unwinder from encountering a NULL stack frame pointer
when CONFIG_UNWINDER_FRAME_POINTER is enabled

Fixes: 14619d912b65 ("x86/fred: FRED entry/exit and dispatch code")
Signed-off-by: David Stevens <stevensd@xxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Acked-by: H. Peter Anvin (Intel) <hpa@xxxxxxxxx>
Link: https://patch.msgid.link/20260424191456.2679717-12-stevensd@xxxxxxxxxx
---
arch/x86/entry/entry_64_fred.S | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/x86/entry/entry_64_fred.S b/arch/x86/entry/entry_64_fred.S
index 0d2768a..b98f894 100644
--- a/arch/x86/entry/entry_64_fred.S
+++ b/arch/x86/entry/entry_64_fred.S
@@ -7,6 +7,7 @@
#include <linux/kvm_types.h>

#include <asm/asm.h>
+#include <asm/frame.h>
#include <asm/fred.h>
#include <asm/segment.h>

@@ -19,6 +20,7 @@
UNWIND_HINT_END_OF_STACK
ANNOTATE_NOENDBR
PUSH_AND_CLEAR_REGS
+ ENCODE_FRAME_POINTER
movq %rsp, %rdi /* %rdi -> pt_regs */
.endm