]> www.infradead.org Git - users/willy/pagecache.git/commit
kasan: make report_lock a raw spinlock
authorJared Kangas <jkangas@redhat.com>
Tue, 19 Nov 2024 21:02:34 +0000 (13:02 -0800)
committerAndrew Morton <akpm@linux-foundation.org>
Fri, 6 Dec 2024 03:54:43 +0000 (19:54 -0800)
commite30a0361b8515d424c73c67de1a43e45a13b8ba2
tree5d8fbb6330f81ab02d3a426ba03d9775d8d03e5f
parent091c1dd2d4df6edd1beebe0e5863d4034ade9572
kasan: make report_lock a raw spinlock

If PREEMPT_RT is enabled, report_lock is a sleeping spinlock and must not
be locked when IRQs are disabled.  However, KASAN reports may be triggered
in such contexts.  For example:

        char *s = kzalloc(1, GFP_KERNEL);
        kfree(s);
        local_irq_disable();
        char c = *s;  /* KASAN report here leads to spin_lock() */
        local_irq_enable();

Make report_spinlock a raw spinlock to prevent rescheduling when
PREEMPT_RT is enabled.

Link: https://lkml.kernel.org/r/20241119210234.1602529-1-jkangas@redhat.com
Fixes: 342a93247e08 ("locking/spinlock: Provide RT variant header: <linux/spinlock_rt.h>")
Signed-off-by: Jared Kangas <jkangas@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm/kasan/report.c