> From: Christoph Hellwig [mailto:[email protected]] > Sent: Thursday, January 12, 2017 23:53 > To: Dexuan Cui <[email protected]> > Cc: Christoph Hellwig <[email protected]>; [email protected]; Jens Axboe > <[email protected]>; Vitaly Kuznetsov <[email protected]>; linux- > [email protected]; KY Srinivasan <[email protected]>; Chris Valean > (Cloudbase Solutions SRL) <[email protected]> > Subject: Re: [Regression] fstrim hangs on Hyper-V: caused by "block: improve > handling of the magic discard payload" > > Can you check if this debug printk triggers for the discard commands? > > --- > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c > index 888e16e..7ab7d08 100644 > --- a/drivers/scsi/storvsc_drv.c > +++ b/drivers/scsi/storvsc_drv.c > @@ -1031,6 +1031,10 @@ static void storvsc_command_completion(struct > storvsc_cmd_request *cmd_request, > data_transfer_length = 0; > } > > + if (cmd_request->payload->range.len != data_transfer_length) > + printk_ratelimited("request len: %u, transfer len: %u\n", > + cmd_request->payload->range.len, > + data_transfer_length); > scsi_set_resid(scmnd, > cmd_request->payload->range.len - data_transfer_length); >
// I fixed the small building issue (data_transfer_length ==> vm_srb->data_transfer_length). No, the printk doesn't trigger for fstrim. It does trigger at the early boot phase, though. # dmesg |grep len: [ 0.000000] log_buf_len: 134217728 bytes [ 7.073423] request len: 255, transfer len: 12 [ 7.084937] request len: 255, transfer len: 52 [ 7.121728] request len: 64, transfer len: 12 [ 7.121915] request len: 64, transfer len: 12 [ 7.123180] request len: 64, transfer len: 12 [ 7.123367] request len: 64, transfer len: 12 [ 7.127193] request len: 64, transfer len: 12 [ 7.127350] request len: 64, transfer len: 12 [ 7.178930] request len: 255, transfer len: 12 [ 7.179045] request len: 255, transfer len: 52 -- Dexuan
