The quilt patch titled
Subject: s390/traps: unpoison the kernel_stack_overflow()'s pt_regs
has been removed from the -mm tree. Its filename was
s390-traps-unpoison-the-kernel_stack_overflows-pt_regs.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
Subject: s390/traps: unpoison the kernel_stack_overflow()'s pt_regs
Date: Fri, 21 Jun 2024 13:35:17 +0200
This is normally done by the generic entry code, but the
kernel_stack_overflow() flow bypasses it.
Link: https://lkml.kernel.org/r/20240621113706.315500-34-iii@xxxxxxxxxxxxx
Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx>
Acked-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: <kasan-dev@xxxxxxxxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Cc: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Cc: Sven Schnelle <svens@xxxxxxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/s390/kernel/traps.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/arch/s390/kernel/traps.c~s390-traps-unpoison-the-kernel_stack_overflows-pt_regs
+++ a/arch/s390/kernel/traps.c
@@ -27,6 +27,7 @@
#include <linux/uaccess.h>
#include <linux/cpu.h>
#include <linux/entry-common.h>
+#include <linux/kmsan.h>
#include <asm/asm-extable.h>
#include <asm/vtime.h>
#include <asm/fpu.h>
@@ -262,6 +263,11 @@ static void monitor_event_exception(stru
void kernel_stack_overflow(struct pt_regs *regs)
{
+ /*
+ * Normally regs are unpoisoned by the generic entry code, but
+ * kernel_stack_overflow() is a rare case that is called bypassing it.
+ */
+ kmsan_unpoison_entry_regs(regs);
bust_spinlocks(1);
printk("Kernel stack overflow.\n");
show_regs(regs);
_
Patches currently in -mm which might be from iii@xxxxxxxxxxxxx are
