The patch titled
Subject: kasan: disable LOCKDEP when printing reports
has been removed from the -mm tree. Its filename was
kasan-disable-lockdep-when-printing-reports.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Subject: kasan: disable LOCKDEP when printing reports
If LOCKDEP detects a bug while KASAN is printing a report and if
panic_on_warn is set, KASAN will not be able to finish. Disable LOCKDEP
while KASAN is printing a report.
See https://bugzilla.kernel.org/show_bug.cgi?id=202115 for an example
of the issue.
Link: https://lkml.kernel.org/r/c48a2a3288200b07e1788b77365c2f02784cfeb4.1646237226.git.andreyknvl@xxxxxxxxxx
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/kasan/report.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/mm/kasan/report.c~kasan-disable-lockdep-when-printing-reports
+++ a/mm/kasan/report.c
@@ -13,6 +13,7 @@
#include <linux/ftrace.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/lockdep.h>
#include <linux/mm.h>
#include <linux/printk.h>
#include <linux/sched.h>
@@ -148,6 +149,8 @@ static void start_report(unsigned long *
disable_trace_on_warning();
/* Update status of the currently running KASAN test. */
update_kunit_status(sync);
+ /* Do not allow LOCKDEP mangling KASAN reports. */
+ lockdep_off();
/* Make sure we don't end up in loop. */
kasan_disable_current();
spin_lock_irqsave(&report_lock, *flags);
@@ -160,12 +163,13 @@ static void end_report(unsigned long *fl
trace_error_report_end(ERROR_DETECTOR_KASAN,
(unsigned long)addr);
pr_err("==================================================================\n");
- add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
spin_unlock_irqrestore(&report_lock, *flags);
if (panic_on_warn && !test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags))
panic("panic_on_warn set ...\n");
if (kasan_arg_fault == KASAN_ARG_FAULT_PANIC)
panic("kasan.fault=panic set ...\n");
+ add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
+ lockdep_on();
kasan_enable_current();
}
_
Patches currently in -mm which might be from andreyknvl@xxxxxxxxxx are
stacktrace-add-interface-based-on-shadow-call-stack.patch
arm64-scs-save-scs_sp-values-per-cpu-when-switching-stacks.patch
arm64-implement-stack_trace_save_shadow.patch
kasan-use-stack_trace_save_shadow.patch
