> -----Original Message----- > From: James Bottomley [mailto:j...@linux.vnet.ibm.com] > Sent: Saturday, March 4, 2017 1:37 PM > To: KY Srinivasan <k...@microsoft.com>; Stephen Hemminger > <step...@networkplumber.org> > Cc: Hannes Reinecke <h...@suse.de>; Christoph Hellwig <h...@lst.de>; Jens > Axboe <ax...@kernel.dk>; Linus Torvalds <torvalds@linux- > foundation.org>; Martin K. Petersen <martin.peter...@oracle.com>; > Dexuan Cui <de...@microsoft.com>; Long Li <lon...@microsoft.com>; Josh > Poulson <jopou...@microsoft.com>; Adrian Suhov (Cloudbase Solutions SRL) > <v-ads...@microsoft.com>; linux-scsi@vger.kernel.org; Haiyang Zhang > <haiya...@microsoft.com> > Subject: Re: [RFC] hv_storvsc: error handling. > > On Sat, 2017-03-04 at 21:03 +0000, KY Srinivasan wrote: > > > > > -----Original Message----- > > > From: Stephen Hemminger [mailto:step...@networkplumber.org] > > > Sent: Friday, March 3, 2017 4:50 PM > > > To: James Bottomley <james.bottom...@hansenpartnership.com> > > > Cc: Hannes Reinecke <h...@suse.de>; Christoph Hellwig <h...@lst.de>; > > > James Bottomley <j...@linux.vnet.ibm.com>; Jens Axboe > > > <ax...@kernel.dk>; Linus Torvalds <torva...@linux-foundation.org>; > > > Martin K. Petersen <martin.peter...@oracle.com>; KY Srinivasan > > > <k...@microsoft.com>; Dexuan Cui <de...@microsoft.com>; Long Li > > > <lon...@microsoft.com>; Josh Poulson <jopou...@microsoft.com>; > > > Adrian > > > Suhov (Cloudbase Solutions SRL) <v-ads...@microsoft.com>; linux- > > > s...@vger.kernel.org; Haiyang Zhang <haiya...@microsoft.com> > > > Subject: [RFC] hv_storvsc: error handling. > > > > > > Needs more testing but this does fix the observed problem. > > > > > > From: Stephen Hemminger <sthem...@microsoft.com> > > > > > > Subject: [PATCH] hv_storvsc: fix error handling > > > > > > The Hyper-V storvsc SCSI driver was hiding all errors in INQUIRY > > > and > > > MODE_SENSE commands. This caused the scan process to incorrectly > > > think > > > devices were present and online. Also invalid LUN errors were not > > > being handled correctly. > > > > > > This fixes problems booting a GEN2 VM on Hyper-V. It effectively > > > reverts commit 4ed51a21c0f69 ("Staging: hv: storvsc: Fixup > > > srb and scsi status for INQUIRY and MODE_SENSE") > > > > > > Signed-off-by: Stephen Hemminger <sthem...@microsoft.com> > > > --- > > > drivers/scsi/storvsc_drv.c | 48 ++++------------------------------ > > > ------------ > > > 1 file changed, 4 insertions(+), 44 deletions(-) > > > > > > diff --git a/drivers/scsi/storvsc_drv.c > > > b/drivers/scsi/storvsc_drv.c > > > index 638e5f427c90..8cc241fc54b8 100644 > > > --- a/drivers/scsi/storvsc_drv.c > > > +++ b/drivers/scsi/storvsc_drv.c > > > @@ -543,28 +543,6 @@ static void storvsc_host_scan(struct > > > work_struct > > > *work) > > > kfree(wrk); > > > } > > > > > > -static void storvsc_remove_lun(struct work_struct *work) > > > -{ > > > - struct storvsc_scan_work *wrk; > > > - struct scsi_device *sdev; > > > - > > > - wrk = container_of(work, struct storvsc_scan_work, work); > > > - if (!scsi_host_get(wrk->host)) > > > - goto done; > > > - > > > - sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk > > > ->lun); > > > - > > > - if (sdev) { > > > - scsi_remove_device(sdev); > > > - scsi_device_put(sdev); > > > - } > > > - scsi_host_put(wrk->host); > > > - > > > -done: > > > - kfree(wrk); > > > -} > > > - > > > - > > > /* > > > * We can get incoming messages from the host that are not in > > > response to > > > * messages that we have sent out. An example of this would be > > > messages > > > @@ -955,8 +933,7 @@ static void storvsc_handle_error(struct > > > vmscsi_request *vm_srb, > > > } > > > break; > > > case SRB_STATUS_INVALID_LUN: > > > - do_work = true; > > > - process_err_fn = storvsc_remove_lun; > > > + set_host_byte(scmnd, DID_NO_CONNECT); > > > break; > > > case SRB_STATUS_ABORTED: > > > if (vm_srb->srb_status & > > > SRB_STATUS_AUTOSENSE_VALID > > > && > > > @@ -1050,32 +1027,15 @@ static void storvsc_on_io_completion(struct > > > storvsc_device *stor_device, > > > > > > stor_pkt = &request->vstor_packet; > > > > > > - /* > > > - * The current SCSI handling on the host side does > > > - * not correctly handle: > > > - * INQUIRY command with page code parameter set to 0x80 > > > - * MODE_SENSE command with cmd[2] == 0x1c > > > - * > > > - * Setup srb and scsi status so this won't be fatal. > > > - * We do this so we can distinguish truly fatal failues > > > - * (srb status == 0x4) and off-line the device in that > > > case. > > > - */ > > > - > > > - if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) || > > > - (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) { > > > - vstor_packet->vm_srb.scsi_status = 0; > > > - vstor_packet->vm_srb.srb_status = > > > SRB_STATUS_SUCCESS; > > > - } > > > - > > > - > > > /* Copy over the status...etc */ > > > stor_pkt->vm_srb.scsi_status = vstor_packet > > > ->vm_srb.scsi_status; > > > stor_pkt->vm_srb.srb_status = vstor_packet > > > ->vm_srb.srb_status; > > > stor_pkt->vm_srb.sense_info_length = > > > vstor_packet->vm_srb.sense_info_length; > > > > > > - if (vstor_packet->vm_srb.scsi_status != 0 || > > > - vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS) > > > + if (stor_pkt->vm_srb.cdb[0] != INQUIRY && > > > + (vstor_packet->vm_srb.scsi_status != 0 || > > > + vstor_packet->vm_srb.srb_status != > > > SRB_STATUS_SUCCESS)) > > > storvsc_log(device, STORVSC_LOGGING_WARN, > > > "cmd 0x%x scsi status 0x%x srb status > > > 0x%x\n", > > > stor_pkt->vm_srb.cdb[0], > > > -- > > > > This patch gets rid of the ability to "hot remove" LUNs. I don't > > think that can be part of any > > solution. The INQUIRY hack I put in a long time ago was to deal with > > host bugs on prior versions of > > Windows server. WS2016 should not be trigerring this code. Stephen, > > could you please test this patch - > > a quick hack: > > > > From b97f24f224a71a6e745c42e5640045a553eb407c Mon Sep 17 00:00:00 > > 2001 > > From: K. Y. Srinivasan <k...@microsoft.com> > > Date: Sat, 4 Mar 2017 14:00:46 -0700 > > Subject: [PATCH 1/1] scsi: storvsc: Fix a bug in LUN removal code > > Reply-To: k...@microsoft.com > > > > Signed-off-by: K. Y. Srinivasan <k...@microsoft.com> > > --- > > drivers/scsi/storvsc_drv.c | 13 +++++++++++++ > > 1 files changed, 13 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c > > index 05526b7..27eb682 100644 > > --- a/drivers/scsi/storvsc_drv.c > > +++ b/drivers/scsi/storvsc_drv.c > > @@ -885,6 +885,7 @@ static void storvsc_handle_error(struct > > vmscsi_request *vm_srb, > > struct storvsc_scan_work *wrk; > > void (*process_err_fn)(struct work_struct *work); > > bool do_work = false; > > + struct scsi_device *sdev; > > > > switch (SRB_STATUS(vm_srb->srb_status)) { > > case SRB_STATUS_ERROR: > > @@ -911,6 +912,18 @@ static void storvsc_handle_error(struct > > vmscsi_request *vm_srb, > > } > > break; > > case SRB_STATUS_INVALID_LUN: > > + if (!scsi_host_get(host)) { > > + set_host_byte(scmnd, DID_NO_CONNECT); > > + break; > > + } > > + > > + sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, > > wrk->lun); > > + > > + if (!sdev) { > > + set_host_byte(scmnd, DID_NO_CONNECT); > > + break; > > + } > > + > > You're now getting two references (one to the host and one to the > device) that you don't put either in error handling or in > storvsc_remove_lun(). > > Probably you should eliminate the scsi_host_get and scsi_device_lookup > in storvsc_remove_lun() (making it basically remove device put device > put host) and add a host put in the !sdev if above.
Yes; this was a quick hack to prove a theory. This should work (I hope); I will cleanup and resend once Stephen verifies. K. Y > > James
