[PATCH v3 6/7] scsi: blacklist: add VMware ESXi cdrom - broken tray emulation.

Michal Suchanek
2019-10-25T11:21:59Z

The WMware ESXi cdrom identifies itself as:
sr 0:0:0:0: [sr0] scsi3-mmc drive: vendor: "NECVMWarVMware SATA CD001.00"
model: "VMware SATA CD001.00"
with the following get_capabilities print in sr.c:
sr_printk(KERN_INFO, cd,
"scsi3-mmc drive: vendor: \"%s\" model: \"%s\"\n",
cd->device->vendor, cd->device->model);

The model looks like reliable identification while vendor does not.

The drive claims to have a tray and claims to be able to close it.
However, the UI has no notion of a tray - when medium is ejected it is
dropped in the floor and the user must select a medium again before the
drive can be re-loaded. On the kernel side the tray_move call to close
the tray succeeds but the drive state does not change as a result of the
call.

The drive does not in fact emulate the tray state. There are two ways to
get the medium state. One is the SCSI status:

Physical drive:

Fixed format, current; Sense key: Not Ready
Additional sense: Medium not present - tray open
Raw sense data (in hex):
70 00 02 00 00 00 00 0a 00 00 00 00 3a 02 00 00
00 00

Fixed format, current; Sense key: Not Ready
Additional sense: Medium not present - tray closed
Raw sense data (in hex):
70 00 02 00 00 00 00 0a 00 00 00 00 3a 01 00 00
00 00

VMware ESXi:

Fixed format, current; Sense key: Not Ready
Additional sense: Medium not present
Info fld=0x0 [0]
Raw sense data (in hex):
f0 00 02 00 00 00 00 0a 00 00 00 00 3a 00 00 00
00 00

So the tray state is not reported here. Other is medium status which the
kernel prefers if available. Adding a print here gives:

cdrom: get_media_event success: code = 0, door_open = 1, medium_present = 0

door_open is interpreted as open tray. This is fine so long as tray_move
would close the tray when requested or report an error which never
happens on VMware ESXi servers (5.5 and 6.5 tested).

This is a popular virtualization platform so a workaround is worthwhile.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
v2: new patch
v3: change into a blacklist flag - needs testing it still matches, will
try to patch qemu to provide same ID string
---
drivers/scsi/scsi_devinfo.c | 15 +++++++++------
drivers/scsi/sr.c | 6 ++++++
include/scsi/scsi_devinfo.h | 7 ++++++-
3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/scsi_devinfo.c b/drivers/scsi/scsi_devinfo.c
index df14597752ec..f5f51ec527aa 100644
--- a/drivers/scsi/scsi_devinfo.c
+++ b/drivers/scsi/scsi_devinfo.c
@@ -252,6 +252,7 @@ static struct {
{"TOSHIBA", "CD-ROM", NULL, BLIST_ISROM},
{"Traxdata", "CDR4120", NULL, BLIST_NOLUN}, /* locks up */
{"USB2.0", "SMARTMEDIA/XD", NULL, BLIST_FORCELUN | BLIST_INQUIRY_36},
+ {"VMware", "VMware", NULL, BLIST_NO_MATCH_VENDOR | BLIST_NO_TRAY},
{"WangDAT", "Model 2600", "01.7", BLIST_SELECT_NO_ATN},
{"WangDAT", "Model 3200", "02.2", BLIST_SELECT_NO_ATN},
{"WangDAT", "Model 1300", "02.4", BLIST_SELECT_NO_ATN},
@@ -454,10 +455,11 @@ static struct scsi_dev_info_list *scsi_dev_info_list_find(const char *vendor,
/*
* vendor strings must be an exact match
*/
- if (vmax != strnlen(devinfo->vendor,
- sizeof(devinfo->vendor)) ||
- memcmp(devinfo->vendor, vskip, vmax))
- continue;
+ if (!devinfo->flags & BLIST_NO_MATCH_VENDOR)
+ if (vmax != strnlen(devinfo->vendor,
+ sizeof(devinfo->vendor)) ||
+ memcmp(devinfo->vendor, vskip, vmax))
+ continue;

/*
* @model specifies the full string, and
@@ -468,8 +470,9 @@ static struct scsi_dev_info_list *scsi_dev_info_list_find(const char *vendor,
continue;
return devinfo;
} else {
- if (!memcmp(devinfo->vendor, vendor,
- sizeof(devinfo->vendor)) &&
+ if ((!memcmp(devinfo->vendor, vendor,
+ sizeof(devinfo->vendor))
+ || (devinfo->flags & BLIST_NO_MATCH_VENDOR)) &&
!memcmp(devinfo->model, model,
sizeof(devinfo->model)))
return devinfo;
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 4664fdf75c0f..07c319494bf4 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -58,6 +58,7 @@
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h> /* For the door lock/unlock commands */
+#include <scsi/scsi_devinfo.h>

#include "scsi_logging.h"
#include "sr.h"
@@ -922,6 +923,11 @@ static void get_capabilities(struct scsi_cd *cd)
buffer[n + 4] & 0x20 ? "xa/form2 " : "", /* can read xa/from2 */
buffer[n + 5] & 0x01 ? "cdda " : "", /* can read audio data */
loadmech[buffer[n + 6] >> 5]);
+ if (cd->device->sdev_bflags & BLIST_NO_TRAY) {
+ buffer[n + 6] &= ~(0xff << 5);
+ sr_printk(KERN_INFO, cd,
+ "Tray emulation bug workaround: tray -> caddy\n");
+ }
if ((buffer[n + 6] >> 5) == 0)
/* caddy drives can't close tray... */
cd->cdi.mask |= CDC_CLOSE_TRAY;
diff --git a/include/scsi/scsi_devinfo.h b/include/scsi/scsi_devinfo.h
index 3fdb322d4c4b..17ea96936cc6 100644
--- a/include/scsi/scsi_devinfo.h
+++ b/include/scsi/scsi_devinfo.h
@@ -67,8 +67,13 @@
#define BLIST_RETRY_ITF ((__force blist_flags_t)(1ULL << 32))
/* Always retry ABORTED_COMMAND with ASC 0xc1 */
#define BLIST_RETRY_ASC_C1 ((__force blist_flags_t)(1ULL << 33))
+/* Device reports to have a tray but it cannot be operated reliably */
+#define BLIST_NO_TRAY ((__force blist_flags_t)(1ULL << 34))
+/* Vendor string is bogus */
+#define BLIST_NO_MATCH_VENDOR ((__force blist_flags_t)(1ULL << 35))

-#define __BLIST_LAST_USED BLIST_RETRY_ASC_C1
+
+#define __BLIST_LAST_USED BLIST_NO_MATCH_VENDOR

#define __BLIST_HIGH_UNUSED (~(__BLIST_LAST_USED | \
(__force blist_flags_t) \
--
2.23.0