> -----Original Message----- > From: Stephen Hemminger [mailto:[email protected]] > Sent: Monday, March 6, 2017 8:36 AM > To: KY Srinivasan <[email protected]> > Cc: James Bottomley <[email protected]>; Hannes > Reinecke <[email protected]>; Christoph Hellwig <[email protected]>; James > Bottomley <[email protected]>; Jens Axboe <[email protected]>; > Linus Torvalds <[email protected]>; Martin K. Petersen > <[email protected]>; Dexuan Cui <[email protected]>; Long > Li <[email protected]>; Josh Poulson <[email protected]>; Adrian > Suhov (Cloudbase Solutions SRL) <[email protected]>; linux- > [email protected]; Haiyang Zhang <[email protected]> > Subject: Re: [RFC] hv_storvsc: error handling. > > On Sat, 4 Mar 2017 21:03:41 +0000 > KY Srinivasan <[email protected]> wrote: > > > > -----Original Message----- > > > From: Stephen Hemminger [mailto:[email protected]] > > > Sent: Friday, March 3, 2017 4:50 PM > > > To: James Bottomley <[email protected]> > > > Cc: Hannes Reinecke <[email protected]>; Christoph Hellwig <[email protected]>; > > > James Bottomley <[email protected]>; Jens Axboe > > > <[email protected]>; Linus Torvalds <[email protected]>; > > > Martin K. Petersen <[email protected]>; KY Srinivasan > > > <[email protected]>; Dexuan Cui <[email protected]>; Long Li > > > <[email protected]>; Josh Poulson <[email protected]>; > Adrian > > > Suhov (Cloudbase Solutions SRL) <[email protected]>; linux- > > > [email protected]; Haiyang Zhang <[email protected]> > > > Subject: [RFC] hv_storvsc: error handling. > > > > > > Needs more testing but this does fix the observed problem. > > > > > > From: Stephen Hemminger <[email protected]> > > > > > > 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 <[email protected]> > > > --- > > > 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 <[email protected]> > > Date: Sat, 4 Mar 2017 14:00:46 -0700 > > Subject: [PATCH 1/1] scsi: storvsc: Fix a bug in LUN removal code > > Reply-To: [email protected] > > > > Signed-off-by: K. Y. Srinivasan <[email protected]> > > --- > > 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; > > + } > > + > > do_work = true; > > process_err_fn = storvsc_remove_lun; > > break; > > I will try it, but it can't work for two reasons. > First, the INVALID_LUN error is masked off on INQUIRY in current code. > Second, the scsi_device is instantiated already as part of scan probe process > before it gets here.
Was the invalid LUN in the LUN0 position. Inquiry of LUN0 support (when LUN0 is not populated) was added only recently to address host side issue. > > The best solution so far is: > - remove old INQUIRY/SENSE error masking > + add new workaround for INQUIRY of device id on LUN 0 > which appears to be the reason for old masking > + return errors on missing LUN > + provide better transport services for hot remove (rather > than detecting by failed I/O). This the mechanism used by the host for notifying LUN removal - invalid LUN error code. K. Y >
