From patchwork Mon Dec 2 12:11:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikita Zhandarovich X-Patchwork-Id: 846664 Received: from exchange.fintech.ru (exchange.fintech.ru [195.54.195.159]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 60A50209F57; Mon, 2 Dec 2024 12:11:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.54.195.159 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733141484; cv=none; b=OfOo+G7zd2pGFjg8Dowki4mF7MZgTTfZmZO1v7rnIcgTgFbWB7J7fqyka+6K1eYT9rfHcg3MuIkP3MvM2LTlqQJcc0O58FWWrGt3xlwT2Q7ouPrI2BJVdGq8ONUvhRv/YvLxDR/Hy5XzYXY0ZS5HHqgKj8aIwUqYOiJA/m//kbk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733141484; c=relaxed/simple; bh=opxfZQjUwIBGxhGvxvuJA2xcdMKZ94HOj9VRYSyC0T8=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Mr/Q25G28utUpxTnqgYcIsvX663kVdApuB+sfkhaRve41rZil7oPAr+Mvw1FSKJ8gHfilzTg+ytLD9ocuKP0v8iVlk9WuKWMfyrrQ4AQRmmy/ZdLtJQ8D21PThjcovYknqr4QfHU84EiqXK/b//2sklZM226/VQniUuKnWd6BGc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=fintech.ru; spf=pass smtp.mailfrom=fintech.ru; arc=none smtp.client-ip=195.54.195.159 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=fintech.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fintech.ru Received: from Ex16-01.fintech.ru (10.0.10.18) by exchange.fintech.ru (195.54.195.169) with Microsoft SMTP Server (TLS) id 14.3.498.0; Mon, 2 Dec 2024 15:11:12 +0300 Received: from localhost (10.0.253.138) by Ex16-01.fintech.ru (10.0.10.18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.4; Mon, 2 Dec 2024 15:11:12 +0300 From: Nikita Zhandarovich To: Greg Kroah-Hartman , Sasha Levin , CC: Nikita Zhandarovich , "Rafael J. Wysocki" , Len Brown , , , Subject: [PATCH 5.10.y 1/1] ACPI: PAD: fix crash in exit_round_robin() Date: Mon, 2 Dec 2024 04:11:04 -0800 Message-ID: <20241202121104.35898-2-n.zhandarovich@fintech.ru> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20241202121104.35898-1-n.zhandarovich@fintech.ru> References: <20241202121104.35898-1-n.zhandarovich@fintech.ru> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: Ex16-02.fintech.ru (10.0.10.19) To Ex16-01.fintech.ru (10.0.10.18) From: Seiji Nishikawa [ Upstream commit 0a2ed70a549e61c5181bad5db418d223b68ae932 ] The kernel occasionally crashes in cpumask_clear_cpu(), which is called within exit_round_robin(), because when executing clear_bit(nr, addr) with nr set to 0xffffffff, the address calculation may cause misalignment within the memory, leading to access to an invalid memory address. ---------- BUG: unable to handle kernel paging request at ffffffffe0740618 ... CPU: 3 PID: 2919323 Comm: acpi_pad/14 Kdump: loaded Tainted: G OE X --------- - - 4.18.0-425.19.2.el8_7.x86_64 #1 ... RIP: 0010:power_saving_thread+0x313/0x411 [acpi_pad] Code: 89 cd 48 89 d3 eb d1 48 c7 c7 55 70 72 c0 e8 64 86 b0 e4 c6 05 0d a1 02 00 01 e9 bc fd ff ff 45 89 e4 42 8b 04 a5 20 82 72 c0 48 0f b3 05 f4 9c 01 00 42 c7 04 a5 20 82 72 c0 ff ff ff ff 31 RSP: 0018:ff72a5d51fa77ec8 EFLAGS: 00010202 RAX: 00000000ffffffff RBX: ff462981e5d8cb80 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246 RBP: ff46297556959d80 R08: 0000000000000382 R09: ff46297c8d0f38d8 R10: 0000000000000000 R11: 0000000000000001 R12: 000000000000000e R13: 0000000000000000 R14: ffffffffffffffff R15: 000000000000000e FS: 0000000000000000(0000) GS:ff46297a800c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffe0740618 CR3: 0000007e20410004 CR4: 0000000000771ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: ? acpi_pad_add+0x120/0x120 [acpi_pad] kthread+0x10b/0x130 ? set_kthread_struct+0x50/0x50 ret_from_fork+0x1f/0x40 ... CR2: ffffffffe0740618 crash> dis -lr ffffffffc0726923 ... /usr/src/debug/kernel-4.18.0-425.19.2.el8_7/linux-4.18.0-425.19.2.el8_7.x86_64/./include/linux/cpumask.h: 114 0xffffffffc0726918 : mov %r12d,%r12d /usr/src/debug/kernel-4.18.0-425.19.2.el8_7/linux-4.18.0-425.19.2.el8_7.x86_64/./include/linux/cpumask.h: 325 0xffffffffc072691b : mov -0x3f8d7de0(,%r12,4),%eax /usr/src/debug/kernel-4.18.0-425.19.2.el8_7/linux-4.18.0-425.19.2.el8_7.x86_64/./arch/x86/include/asm/bitops.h: 80 0xffffffffc0726923 : lock btr %rax,0x19cf4(%rip) # 0xffffffffc0740620 crash> px tsk_in_cpu[14] $66 = 0xffffffff crash> px 0xffffffffc072692c+0x19cf4 $99 = 0xffffffffc0740620 crash> sym 0xffffffffc0740620 ffffffffc0740620 (b) pad_busy_cpus_bits [acpi_pad] crash> px pad_busy_cpus_bits[0] $42 = 0xfffc0 ---------- To fix this, ensure that tsk_in_cpu[tsk_index] != -1 before calling cpumask_clear_cpu() in exit_round_robin(), just as it is done in round_robin_cpu(). Signed-off-by: Seiji Nishikawa Link: https://patch.msgid.link/20240825141352.25280-1-snishika@redhat.com [ rjw: Subject edit, avoid updates to the same value ] Signed-off-by: Rafael J. Wysocki [ Nikita: fix conflict due to missing blank line from commit c8eb628cbdd9 ("ACPI: acpi_pad: add a missed blank line after declarations"). ] Signed-off-by: Nikita Zhandarovich --- drivers/acpi/acpi_pad.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/acpi_pad.c b/drivers/acpi/acpi_pad.c index b84ab722feb4..6d592d8655cd 100644 --- a/drivers/acpi/acpi_pad.c +++ b/drivers/acpi/acpi_pad.c @@ -128,8 +128,11 @@ static void round_robin_cpu(unsigned int tsk_index) static void exit_round_robin(unsigned int tsk_index) { struct cpumask *pad_busy_cpus = to_cpumask(pad_busy_cpus_bits); - cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus); - tsk_in_cpu[tsk_index] = -1; + + if (tsk_in_cpu[tsk_index] != -1) { + cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus); + tsk_in_cpu[tsk_index] = -1; + } } static unsigned int idle_pct = 5; /* percentage */