From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0BAC725782D; Mon, 23 Mar 2026 15:01:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774278088; cv=none; b=FSwM8orYWz8+bpG6BXvKobDqk6HWcCtxowGXWqf1nlTQ1wJ3AJdLeV2RixCKBDMDXpkqdFQZ5ZsC3axI2EC+Jylgi81NXo49vqOdY/VQ2NrfRjEU80tAJRf/PLSL4/mgK6yq/M5F7lT10QQfOhjuMOw6cXjo6qXKVo3XC6bramA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774278088; c=relaxed/simple; bh=gLwkZgDe8nNTK3kubJk5M0sQqopkpVL1Re8W+2HcD7E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VwPIu0qHd5FrjbcMsPjzW5e0N5pX4lWwP910XFK1ESZEQnoHs3WuJGfLClXy7tHqQHtUKIDrdmKQYopnJkt6VNitlc1v97kSBksQmR53LTyME1KV2FRYDIiiLrSKKoZ4lflrmG69kWfQTSTyD3mBNWxGfrQ0L/5Y3Xa8rPf8LEM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JJreKPCr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="JJreKPCr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5050AC4CEF7; Mon, 23 Mar 2026 15:01:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1774278087; bh=gLwkZgDe8nNTK3kubJk5M0sQqopkpVL1Re8W+2HcD7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JJreKPCrUUiwDh1K2jIi0MvNEzmqOSYvKqMD5Px36/ptk5s7TNzq4K8oSeNTVlQtX XC2BICeBKSvvCp4SevBeEo19MzHFMdjg0upeL8a/4xsmvbZa0e/dFbHLCTlvLLd/39 yRoaTFSbmVrUK+c4WYHTuz/J5qscYI0aWkt5yJfQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jan Kiszka , Florian Bezdeka , Michael Kelley , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 6.6 198/567] scsi: storvsc: Fix scheduling while atomic on PREEMPT_RT Date: Mon, 23 Mar 2026 14:41:58 +0100 Message-ID: <20260323134538.747579285@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260323134533.749096647@linuxfoundation.org> References: <20260323134533.749096647@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kiszka [ Upstream commit 57297736c08233987e5d29ce6584c6ca2a831b12 ] This resolves the follow splat and lock-up when running with PREEMPT_RT enabled on Hyper-V: [ 415.140818] BUG: scheduling while atomic: stress-ng-iomix/1048/0x00000002 [ 415.140822] INFO: lockdep is turned off. [ 415.140823] Modules linked in: intel_rapl_msr intel_rapl_common intel_uncore_frequency_common intel_pmc_core pmt_telemetry pmt_discovery pmt_class intel_pmc_ssram_telemetry intel_vsec ghash_clmulni_intel aesni_intel rapl binfmt_misc nls_ascii nls_cp437 vfat fat snd_pcm hyperv_drm snd_timer drm_client_lib drm_shmem_helper snd sg soundcore drm_kms_helper pcspkr hv_balloon hv_utils evdev joydev drm configfs efi_pstore nfnetlink vsock_loopback vmw_vsock_virtio_transport_common hv_sock vmw_vsock_vmci_transport vsock vmw_vmci efivarfs autofs4 ext4 crc16 mbcache jbd2 sr_mod sd_mod cdrom hv_storvsc serio_raw hid_generic scsi_transport_fc hid_hyperv scsi_mod hid hv_netvsc hyperv_keyboard scsi_common [ 415.140846] Preemption disabled at: [ 415.140847] [] storvsc_queuecommand+0x2e1/0xbe0 [hv_storvsc] [ 415.140854] CPU: 8 UID: 0 PID: 1048 Comm: stress-ng-iomix Not tainted 6.19.0-rc7 #30 PREEMPT_{RT,(full)} [ 415.140856] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 09/04/2024 [ 415.140857] Call Trace: [ 415.140861] [ 415.140861] ? storvsc_queuecommand+0x2e1/0xbe0 [hv_storvsc] [ 415.140863] dump_stack_lvl+0x91/0xb0 [ 415.140870] __schedule_bug+0x9c/0xc0 [ 415.140875] __schedule+0xdf6/0x1300 [ 415.140877] ? rtlock_slowlock_locked+0x56c/0x1980 [ 415.140879] ? rcu_is_watching+0x12/0x60 [ 415.140883] schedule_rtlock+0x21/0x40 [ 415.140885] rtlock_slowlock_locked+0x502/0x1980 [ 415.140891] rt_spin_lock+0x89/0x1e0 [ 415.140893] hv_ringbuffer_write+0x87/0x2a0 [ 415.140899] vmbus_sendpacket_mpb_desc+0xb6/0xe0 [ 415.140900] ? rcu_is_watching+0x12/0x60 [ 415.140902] storvsc_queuecommand+0x669/0xbe0 [hv_storvsc] [ 415.140904] ? HARDIRQ_verbose+0x10/0x10 [ 415.140908] ? __rq_qos_issue+0x28/0x40 [ 415.140911] scsi_queue_rq+0x760/0xd80 [scsi_mod] [ 415.140926] __blk_mq_issue_directly+0x4a/0xc0 [ 415.140928] blk_mq_issue_direct+0x87/0x2b0 [ 415.140931] blk_mq_dispatch_queue_requests+0x120/0x440 [ 415.140933] blk_mq_flush_plug_list+0x7a/0x1a0 [ 415.140935] __blk_flush_plug+0xf4/0x150 [ 415.140940] __submit_bio+0x2b2/0x5c0 [ 415.140944] ? submit_bio_noacct_nocheck+0x272/0x360 [ 415.140946] submit_bio_noacct_nocheck+0x272/0x360 [ 415.140951] ext4_read_bh_lock+0x3e/0x60 [ext4] [ 415.140995] ext4_block_write_begin+0x396/0x650 [ext4] [ 415.141018] ? __pfx_ext4_da_get_block_prep+0x10/0x10 [ext4] [ 415.141038] ext4_da_write_begin+0x1c4/0x350 [ext4] [ 415.141060] generic_perform_write+0x14e/0x2c0 [ 415.141065] ext4_buffered_write_iter+0x6b/0x120 [ext4] [ 415.141083] vfs_write+0x2ca/0x570 [ 415.141087] ksys_write+0x76/0xf0 [ 415.141089] do_syscall_64+0x99/0x1490 [ 415.141093] ? rcu_is_watching+0x12/0x60 [ 415.141095] ? finish_task_switch.isra.0+0xdf/0x3d0 [ 415.141097] ? rcu_is_watching+0x12/0x60 [ 415.141098] ? lock_release+0x1f0/0x2a0 [ 415.141100] ? rcu_is_watching+0x12/0x60 [ 415.141101] ? finish_task_switch.isra.0+0xe4/0x3d0 [ 415.141103] ? rcu_is_watching+0x12/0x60 [ 415.141104] ? __schedule+0xb34/0x1300 [ 415.141106] ? hrtimer_try_to_cancel+0x1d/0x170 [ 415.141109] ? do_nanosleep+0x8b/0x160 [ 415.141111] ? hrtimer_nanosleep+0x89/0x100 [ 415.141114] ? __pfx_hrtimer_wakeup+0x10/0x10 [ 415.141116] ? xfd_validate_state+0x26/0x90 [ 415.141118] ? rcu_is_watching+0x12/0x60 [ 415.141120] ? do_syscall_64+0x1e0/0x1490 [ 415.141121] ? do_syscall_64+0x1e0/0x1490 [ 415.141123] ? rcu_is_watching+0x12/0x60 [ 415.141124] ? do_syscall_64+0x1e0/0x1490 [ 415.141125] ? do_syscall_64+0x1e0/0x1490 [ 415.141127] ? irqentry_exit+0x140/0x7e0 [ 415.141129] entry_SYSCALL_64_after_hwframe+0x76/0x7e get_cpu() disables preemption while the spinlock hv_ringbuffer_write is using is converted to an rt-mutex under PREEMPT_RT. Signed-off-by: Jan Kiszka Tested-by: Florian Bezdeka Reviewed-by: Michael Kelley Tested-by: Michael Kelley Link: https://patch.msgid.link/0c7fb5cd-fb21-4760-8593-e04bade84744@siemens.com Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/storvsc_drv.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 9dcad02ce4895..106bccaac4276 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -1861,8 +1861,9 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd) cmd_request->payload_sz = payload_sz; /* Invokes the vsc to start an IO */ - ret = storvsc_do_io(dev, cmd_request, get_cpu()); - put_cpu(); + migrate_disable(); + ret = storvsc_do_io(dev, cmd_request, smp_processor_id()); + migrate_enable(); if (ret) scsi_dma_unmap(scmnd); -- 2.51.0