From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: [PATCH v12 0/6] SCSI device removal fixes Date: Thu, 27 Jun 2013 16:51:34 +0200 Message-ID: <51CC5176.90609@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from jacques.telenet-ops.be ([195.130.132.50]:59085 "EHLO jacques.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751663Ab3F0Ovh (ORCPT ); Thu, 27 Jun 2013 10:51:37 -0400 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: Mike Christie , Hannes Reinecke , Chanho Min , Joe Lawrence , linux-scsi , David Milburn Fix a few issues related to SCSI device removal: - Fix a race between starved list processing and device removal that can trigger a kernel oops. - Avoid that __scsi_remove_device() is called twice for the same SCSI device, which also can cause a kernel oops. - Restrict the SCSI device state changes allowed via sysfs. - Avoid that invoking scsi_device_set_state() triggers a race. - Avoid re-enabling I/O after the transport layer became offline. Changes compared to v11: - Left out a patch that was not a device removal bug fix. - Left out the patches about which there is not yet an agreement. Changes compared to v10: - Rebased and retested on top of Linux kernel v3.10-rc5. Changes compared to v9: - Changed one WARN_ON() statement into a WARN() statement. Changes compared to v8: - Addressed the feedback from Joe Lawrence - dropped the patch that makes scsi_remove_host() wait until the last sdev user is gone. - Eliminated Scsi_Host.tmf_in_progress since it duplicates state information available in Scsi_Host.eh_active. - Added a patch to avoid reenabling I/O after the transport layer became offline. Changes compared to v7: - Addressed the review comments posted by Hannes Reinecke and Rolf Eike Beer. - Modified patch "Make scsi_remove_host() wait until error handling finished" such that it is also safe for SCSI timeout values below the maximum LLD response time by modifying scsi_send_eh_cmnd() such that it does not invoke any LLD code after scsi_remove_host() started. - Added a patch to save and restore the host_scribble field. - Refined / clarified several patch descriptions. - Rebased and retested on top of kernel v3.8-rc6. Changes compared to v6: - Dropped the first six patches since Jens queued these for 3.8. - Added patch to avoid that __scsi_remove_device() is invoked twice. - Restore error recovery in the SHOST_CANCEL state. Changes compared to v5: - Avoid that block layer work can be scheduled on a dead queue. - Do not invoke any SCSI LLD callback after scsi_remove_host() finished. - Stop error handling as soon as scsi_remove_host() started. - Remove the unused function bsg_goose_queue(). - Avoid that scsi_device_set_state() triggers a race condition. Changes compared to v4: - Moved queue_flag_set(QUEUE_FLAG_DEAD, q) from blk_drain_queue() into blk_cleanup_queue(). - Declared the new __blk_run_queue_uncond() function inline. Checked in the generated assembler code that this function is really inlined in __blk_run_queue(). - Elaborated several patch descriptions. - Added sparse annotations to scsi_request_fn(). - Split several patches. Changes compared to v3: - Fixed a race condition by setting QUEUE_FLAG_DEAD earlier. - Added a patch for fixing a race between starved list processing and device removal to this series. Changes compared to v2: - Split second patch into two patches. - Refined patch descriptions. Changes compared to v1: - Included a patch to rename QUEUE_FLAG_DEAD. - Refined the descriptions of the __blk_run_queue_uncond() and blk_cleanup_queue() functions.