-----Original Message----- From: Sergei Trofimovich [mailto:slyich@gmail.com] Sent: Wednesday, March 3, 2021 2:56 AM To: John Paul Adrian Glaubitz ; Don Brace - C33706 ; storagedev ; linux-scsi@vger.kernel.org Cc: linux-ia64@vger.kernel.org; linux-kernel@vger.kernel.org; Joe Szczypek ; Scott Benesh - C33703 ; Scott Teel - C33730 ; Tomas Henzl ; Martin K. Petersen Subject: Re: [bisected] 5.12-rc1 hpsa regression: "scsi: hpsa: Correct dev cmds outstanding for retried cmds" breaks hpsa P600 EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe On Wed, 3 Mar 2021 00:22:36 +0000 Sergei Trofimovich wrote: > On Tue, 2 Mar 2021 23:31:32 +0100 > John Paul Adrian Glaubitz wrote: > > > Hi Sergei! > > > > On 3/2/21 11:26 PM, Sergei Trofimovich wrote: > > > Gave v5.12-rc1 a try today and got a similar boot failure around > > > hpsa queue initialization, but my failure is later: > > > https://dev.gentoo.org/~slyfox/configs/guppy-dmesg-5.12-rc1 > > > Maybe I get different error because I flipped on most debugging > > > kernel options :) > > > > > > Looks like 'ERROR: Invalid distance value range' while being very > > > scary are harmless. It's just a new spammy way for kernel to > > > report lack of NUMA config on the machine (no SRAT and SLIT ACPI > > > tables). > > > > > > At least I get hpsa detected on PCI bus. But I guess it's > > > discovered configuration is very wrong as I get unaligned accesses: > > > [ 19.811570] kernel unaligned access to 0xe000000105dd8295, ip=0xa000000100b874d1 Running pahole before the patch: struct CommandList { struct CommandListHeader Header; /* 0 20 */ struct RequestBlock Request; /* 20 20 */ struct ErrDescriptor ErrDesc; /* 40 12 */ struct SGDescriptor SG[32]; /* 52 512 */ /* --- cacheline 8 boundary (512 bytes) was 52 bytes ago --- */ u32 busaddr; /* 564 4 */ struct ErrorInfo * err_info; /* 568 8 */ /* --- cacheline 9 boundary (576 bytes) --- */ struct ctlr_info * h; /* 576 8 */ int cmd_type; /* 584 4 */ long int cmdindex; /* 588 8 */ struct completion * waiting; /* 596 8 */ struct scsi_cmnd * scsi_cmd; /* 604 8 */ struct work_struct work; /* 612 32 */ /* --- cacheline 10 boundary (640 bytes) was 4 bytes ago --- */ struct hpsa_scsi_dev_t * phys_disk; /* 644 8 */ int abort_pending; /* 652 4 */ struct hpsa_scsi_dev_t * device; /* 656 8 */ atomic_t refcount; /* 664 4 */ /* size: 768, cachelines: 12, members: 16 */ /* padding: 100 */ } __attribute__((__aligned__(128))); Pahole after the patch: struct CommandList { struct CommandListHeader Header; /* 0 20 */ struct RequestBlock Request; /* 20 20 */ struct ErrDescriptor ErrDesc; /* 40 12 */ struct SGDescriptor SG[32]; /* 52 512 */ /* --- cacheline 8 boundary (512 bytes) was 52 bytes ago --- */ u32 busaddr; /* 564 4 */ struct ErrorInfo * err_info; /* 568 8 */ /* --- cacheline 9 boundary (576 bytes) --- */ struct ctlr_info * h; /* 576 8 */ int cmd_type; /* 584 4 */ long int cmdindex; /* 588 8 */ struct completion * waiting; /* 596 8 */ struct scsi_cmnd * scsi_cmd; /* 604 8 */ struct work_struct work; /* 612 32 */ /* --- cacheline 10 boundary (640 bytes) was 4 bytes ago --- */ struct hpsa_scsi_dev_t * phys_disk; /* 644 8 */ struct hpsa_scsi_dev_t * device; /* 652 8 */ bool retry_pending; /* 660 1 */ atomic_t refcount; /* 661 4 */ /* size: 768, cachelines: 12, members: 16 */ /* padding: 103 */ } __attribute__((__aligned__(128))); So, I did replace abort_pending field (an int) with retry_pending (bool) Can I send you a patch to just rename abort_pending to retry_pending using the same type and position? It will mean some minor code changes in the driver... With the above changes, pahole is the same struct CommandList { struct CommandListHeader Header; /* 0 20 */ struct RequestBlock Request; /* 20 20 */ struct ErrDescriptor ErrDesc; /* 40 12 */ struct SGDescriptor SG[32]; /* 52 512 */ /* --- cacheline 8 boundary (512 bytes) was 52 bytes ago --- */ u32 busaddr; /* 564 4 */ struct ErrorInfo * err_info; /* 568 8 */ /* --- cacheline 9 boundary (576 bytes) --- */ struct ctlr_info * h; /* 576 8 */ int cmd_type; /* 584 4 */ long int cmdindex; /* 588 8 */ struct completion * waiting; /* 596 8 */ struct scsi_cmnd * scsi_cmd; /* 604 8 */ struct work_struct work; /* 612 32 */ /* --- cacheline 10 boundary (640 bytes) was 4 bytes ago --- */ struct hpsa_scsi_dev_t * phys_disk; /* 644 8 */ int retry_pending; /* 652 4 */ struct hpsa_scsi_dev_t * device; /* 656 8 */ atomic_t refcount; /* 664 4 */ /* size: 768, cachelines: 12, members: 16 */ /* padding: 100 */ } __attribute__((__aligned__(128))); > > > > > > Bisecting now. > > > > Sounds good. I guess we should get Jens' fix for the signal > > regression merged as well as your two fixes for strace. > > "bisected" (cheated halfway through) and verified that reverting > f749d8b7a9896bc6e5ffe104cc64345037e0b152 makes rx3600 boot again. > > CCing authors who might be able to help us here. > > commit f749d8b7a9896bc6e5ffe104cc64345037e0b152 > Author: Don Brace > Date: Mon Feb 15 16:26:57 2021 -0600 > > scsi: hpsa: Correct dev cmds outstanding for retried cmds > > Prevent incrementing device->commands_outstanding for ioaccel command > retries that are driver initiated. If the command goes through the retry > path, the device->commands_outstanding counter has already accounted for > the number of commands outstanding to the device. Only commands going > through function hpsa_cmd_resolve_events decrement this counter. > > - ioaccel commands go to either HBA disks or to logical volumes comprised > of SSDs. > > The extra increment is causing device resets to hang. > > - Resets wait for all device outstanding commands to complete before > returning. > > Replace unused field abort_pending with retry_pending. This is a > maintenance driver so these changes have the least impact/risk. > > Link: https://lore.kernel.org/r/161342801747.29388.13045495968308188518.stgit@brunhilda > Tested-by: Joe Szczypek > Reviewed-by: Scott Benesh > Reviewed-by: Scott Teel > Reviewed-by: Tomas Henzl > Signed-off-by: Don Brace > Signed-off-by: Martin K. Petersen > > Don, do you happen to know why this patch caused some controller init > failure for device > 14:01.0 RAID bus controller: Hewlett-Packard Company Smart Array > P600 ? > > Boot failure: > https://dev.gentoo.org/~slyfox/configs/guppy-dmesg-5.12-rc1 > Boot success: > https://dev.gentoo.org/~slyfox/configs/guppy-dmesg-5.12-rc1-good > > The difference between the two boots is > f749d8b7a9896bc6e5ffe104cc64345037e0b152 reverted on top of 5.12-rc1 > in -good case. > > Looks like hpsa controller fails to initialize in bad case (could be a race?). Also CCing hpsa maintainer mailing lists. Looking more into the suspect commit https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f749d8b7a9896bc6e5ffe104cc64345037e0b152 it roughly does the: @@ -448,7 +448,7 @@ struct CommandList { */ struct hpsa_scsi_dev_t *phys_disk; - int abort_pending; + bool retry_pending; struct hpsa_scsi_dev_t *device; atomic_t refcount; /* Must be last to avoid memset in hpsa_cmd_init() */ } __aligned(COMMANDLIST_ALIGNMENT); ... @@ -1151,7 +1151,10 @@ static void __enqueue_cmd_and_start_io(struct ctlr_info *h, { dial_down_lockup_detection_during_fw_flash(h, c); atomic_inc(&h->commands_outstanding); - if (c->device) + /* + * Check to see if the command is being retried. + */ + if (c->device && !c->retry_pending) atomic_inc(&c->device->commands_outstanding); But I don't immediately see anything wrong with it. -- Sergei