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Alexey Makhalov 90ffed2d5e scsi: vmw_pvscsi: Set residual data length conditionally
commit 142c779d05 upstream.

The PVSCSI implementation in the VMware hypervisor under specific
configuration ("SCSI Bus Sharing" set to "Physical") returns zero dataLen
in the completion descriptor for READ CAPACITY(16). As a result, the kernel
can not detect proper disk geometry. This can be recognized by the kernel
message:

  [ 0.776588] sd 1:0:0:0: [sdb] Sector size 0 reported, assuming 512.

The PVSCSI implementation in QEMU does not set dataLen at all, keeping it
zeroed. This leads to a boot hang as was reported by Shmulik Ladkani.

It is likely that the controller returns the garbage at the end of the
buffer. Residual length should be set by the driver in that case. The SCSI
layer will erase corresponding data. See commit bdb2b8cab4 ("[SCSI] erase
invalid data returned by device") for details.

Commit e662502b3a ("scsi: vmw_pvscsi: Set correct residual data length")
introduced the issue by setting residual length unconditionally, causing
the SCSI layer to erase the useful payload beyond dataLen when this value
is returned as 0.

As a result, considering existing issues in implementations of PVSCSI
controllers, we do not want to call scsi_set_resid() when dataLen ==
0. Calling scsi_set_resid() has no effect if dataLen equals buffer length.

Link: https://lore.kernel.org/lkml/20210824120028.30d9c071@blondie/
Link: https://lore.kernel.org/r/20211220190514.55935-1-amakhalov@vmware.com
Fixes: e662502b3a ("scsi: vmw_pvscsi: Set correct residual data length")
Cc: Matt Wang <wwentao@vmware.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Vishal Bhakta <vbhakta@vmware.com>
Cc: VMware PV-Drivers <pv-drivers@vmware.com>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: linux-scsi@vger.kernel.org
Cc: stable@vger.kernel.org
Reported-and-suggested-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-05 12:42:39 +01:00
arch efi: Move efifb_setup_from_dmi() prototype from arch headers 2022-01-05 12:42:34 +01:00
block iocost: Fix divide-by-zero on donation from low hweight cgroup 2021-12-22 09:32:48 +01:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto crypto: pcrypt - Delay write to padata->info 2021-11-18 19:16:44 +01:00
Documentation Input: i8042 - add deferred probe support 2022-01-05 12:42:32 +01:00
drivers scsi: vmw_pvscsi: Set residual data length conditionally 2022-01-05 12:42:39 +01:00
fs netfs: fix parameter of cleanup() 2021-12-29 12:28:59 +01:00
include uapi: fix linux/nfc.h userspace compilation errors 2022-01-05 12:42:37 +01:00
init init: make unknown command line param message clearer 2021-11-18 19:17:11 +01:00
ipc shm: extend forced shm destroy to support objects from several IPC nses 2021-11-25 09:48:42 +01:00
kernel kernel/crash_core: suppress unknown crashkernel parameter warning 2021-12-29 12:28:49 +01:00
lib siphash: use _unaligned version by default 2021-12-08 09:04:47 +01:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm kfence: fix memory leak when cat kfence objects 2021-12-29 12:29:00 +01:00
net net/ncsi: check for error return from call to nla_put_u32 2022-01-05 12:42:37 +01:00
samples samples/bpf: Fix incorrect use of strlen in xdp_redirect_cpu 2021-11-25 09:48:33 +01:00
scripts recordmcount.pl: fix typo in s390 mcount regex 2022-01-05 12:42:33 +01:00
security selinux: initialize proto variable in selinux_ip_postroute_compat() 2022-01-05 12:42:34 +01:00
sound ALSA: hda: intel-sdw-acpi: go through HDAS ACPI at max depth of 2 2022-01-05 12:42:33 +01:00
tools selftests: net: using ping6 for IPv6 in udpgro_fwd.sh 2022-01-05 12:42:37 +01:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: downgrade two BUG_ONs to WARN_ON_ONCE 2021-12-22 09:32:34 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS drm fixes for 5.15 final 2021-10-28 12:17:01 -07:00
Makefile Linux 5.15.12 2021-12-29 12:29:03 +01:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.