From nobody Fri Jun 19 15:47:29 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 078AAC433EF for ; Fri, 1 Apr 2022 13:46:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346450AbiDANsN (ORCPT ); Fri, 1 Apr 2022 09:48:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43142 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231720AbiDANsL (ORCPT ); Fri, 1 Apr 2022 09:48:11 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E16C31B2557 for ; Fri, 1 Apr 2022 06:46:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1648820781; x=1680356781; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=Dq4ZeuHSuqCc8HBShNDGOUX84T9yRxGqXlCI/ZSyqZE=; b=FAfUzuxIAFIbWs9NfF+wfIfSa1DcOUeexkBSaJRuRy6Et6p5CFiKOrEF gB7RPKZOd3M7Tg1Ecz7ezFrquKOxWo8ppHRCQgQBra2AB1gUb1k1jKWT4 9IK0XmboVj/7nv+eqk8ps2cov5z8EOznMfcW/ov7u2gUCBBBsQXKMGSdY F9y20HWcBrOD+z1BqhOANqzi26Kn8G4D31DenzqgBOVvfWX6Zgm/OruR/ qnfDhf/RdbjFR0ZumgSET5dinXIlRTjY0OkNjSVJ5Jdb9GF13+xW7Mgb8 BM+/a8FDwHkRXvftCSe6xer0Oo13mHjLNm+YQ6gXFiK6GpOagW3oPSK4e A==; X-IronPort-AV: E=McAfee;i="6200,9189,10304"; a="346576008" X-IronPort-AV: E=Sophos;i="5.90,227,1643702400"; d="scan'208";a="346576008" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2022 06:46:21 -0700 X-IronPort-AV: E=Sophos;i="5.90,227,1643702400"; d="scan'208";a="720888741" Received: from zq-optiplex-7090.bj.intel.com ([10.238.156.125]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2022 06:46:18 -0700 From: Zqiang To: ryabinin.a.a@gmail.com, glider@google.com, andreyknvl@gmail.com, dvyukov@google.com, bigeasy@linutronix.de Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v2] kasan: Fix sleeping function called from invalid context on RT kernel Date: Fri, 1 Apr 2022 21:46:49 +0800 Message-Id: <20220401134649.2222485-1-qiang1.zhang@intel.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" BUG: sleeping function called from invalid context at kernel/locking/spinlo= ck_rt.c:46 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0 preempt_count: 1, expected: 0 ........... CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.1-rt16-yocto-preempt-rt #22 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x60/0x8c dump_stack+0x10/0x12 __might_resched.cold+0x13b/0x173 rt_spin_lock+0x5b/0xf0 ___cache_free+0xa5/0x180 qlist_free_all+0x7a/0x160 per_cpu_remove_cache+0x5f/0x70 smp_call_function_many_cond+0x4c4/0x4f0 on_each_cpu_cond_mask+0x49/0xc0 kasan_quarantine_remove_cache+0x54/0xf0 kasan_cache_shrink+0x9/0x10 kmem_cache_shrink+0x13/0x20 acpi_os_purge_cache+0xe/0x20 acpi_purge_cached_objects+0x21/0x6d acpi_initialize_objects+0x15/0x3b acpi_init+0x130/0x5ba do_one_initcall+0xe5/0x5b0 kernel_init_freeable+0x34f/0x3ad kernel_init+0x1e/0x140 ret_from_fork+0x22/0x30 When the kmem_cache_shrink() be called, the IPI was triggered, the ___cache_free() is called in IPI interrupt context, the local-lock or spin-lock will be acquired. on PREEMPT_RT kernel, these lock is replaced with sleepbale rt-spinlock, so the above problem is triggered. fix it by move the qlist_free_allfrom() the IPI interrupt context to the task context when PREEMPT_RT is enabled. Signed-off-by: Zqiang Acked-by: Dmitry Vyukov --- v1->v2: Add raw_spinlock protect per-cpu shrink qlist.=20 mm/kasan/quarantine.c | 40 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 38 insertions(+), 2 deletions(-) diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c index 08291ed33e93..0e33d30abb8d 100644 --- a/mm/kasan/quarantine.c +++ b/mm/kasan/quarantine.c @@ -99,6 +99,17 @@ static unsigned long quarantine_size; static DEFINE_RAW_SPINLOCK(quarantine_lock); DEFINE_STATIC_SRCU(remove_cache_srcu); =20 +#ifdef CONFIG_PREEMPT_RT +struct cpu_shrink_qlist { + raw_spinlock_t lock; + struct qlist_head qlist; +}; + +static DEFINE_PER_CPU(struct cpu_shrink_qlist, shrink_qlist) =3D { + .lock =3D __RAW_SPIN_LOCK_UNLOCKED(shrink_qlist.lock), +}; +#endif + /* Maximum size of the global queue. */ static unsigned long quarantine_max_size; =20 @@ -311,12 +322,23 @@ static void qlist_move_cache(struct qlist_head *from, static void per_cpu_remove_cache(void *arg) { struct kmem_cache *cache =3D arg; - struct qlist_head to_free =3D QLIST_INIT; struct qlist_head *q; - +#ifndef CONFIG_PREEMPT_RT + struct qlist_head to_free =3D QLIST_INIT; +#else + unsigned long flags; + struct cpu_shrink_qlist *sq; +#endif q =3D this_cpu_ptr(&cpu_quarantine); +#ifndef CONFIG_PREEMPT_RT qlist_move_cache(q, &to_free, cache); qlist_free_all(&to_free, cache); +#else + sq =3D this_cpu_ptr(&shrink_qlist); + raw_spin_lock_irqsave(&sq->lock, flags); + qlist_move_cache(q, &sq->qlist, cache); + raw_spin_unlock_irqrestore(&sq->lock, flags); +#endif } =20 /* Free all quarantined objects belonging to cache. */ @@ -324,6 +346,10 @@ void kasan_quarantine_remove_cache(struct kmem_cache *= cache) { unsigned long flags, i; struct qlist_head to_free =3D QLIST_INIT; +#ifdef CONFIG_PREEMPT_RT + int cpu; + struct cpu_shrink_qlist *sq; +#endif =20 /* * Must be careful to not miss any objects that are being moved from @@ -334,6 +360,16 @@ void kasan_quarantine_remove_cache(struct kmem_cache *= cache) */ on_each_cpu(per_cpu_remove_cache, cache, 1); =20 +#ifdef CONFIG_PREEMPT_RT + for_each_online_cpu(cpu) { + sq =3D per_cpu_ptr(&shrink_qlist, cpu); + raw_spin_lock_irqsave(&sq->lock, flags); + qlist_move_cache(&sq->qlist, &to_free, cache); + raw_spin_unlock_irqrestore(&sq->lock, flags); + } + qlist_free_all(&to_free, cache); +#endif + raw_spin_lock_irqsave(&quarantine_lock, flags); for (i =3D 0; i < QUARANTINE_BATCHES; i++) { if (qlist_empty(&global_quarantine[i])) --=20 2.25.1