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Pull powerpc fix from Michael Ellerman:
"One fix for an oops when using SRIOV, introduced by the recent changes
to support compound IOMMU groups.
Thanks to Alexey Kardashevskiy"
* tag 'powerpc-5.0-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/powernv/sriov: Register IOMMU groups for VFs
Pull SCSI fixes from James Bottomley:
"Four small fixes: three in drivers and one in the core.
The core fix is also minor in scope since the bug it fixes is only
known to affect systems using SCSI reservations. Of the driver bugs,
the libsas one is the most major because it can lead to multiple disks
on the same expander not being exposed"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: core: reset host byte in DID_NEXUS_FAILURE case
scsi: libsas: Fix rphy phy_identifier for PHYs with end devices attached
scsi: sd_zbc: Fix sd_zbc_report_zones() buffer allocation
scsi: libiscsi: Fix race between iscsi_xmit_task and iscsi_complete_task
The compound IOMMU group rework moved iommu_register_group() together
in pnv_pci_ioda_setup_iommu_api() (which is a part of
ppc_md.pcibios_fixup). As the result, pnv_ioda_setup_bus_iommu_group()
does not create groups any more, it only adds devices to groups.
This works fine for boot time devices. However IOMMU groups for
SRIOV's VFs were added by pnv_ioda_setup_bus_iommu_group() so this got
broken: pnv_tce_iommu_bus_notifier() expects a group to be registered
for VF and it is not.
This adds missing group registration and adds a NULL pointer check
into the bus notifier so we won't crash if there is no group, although
it is not expected to happen now because of the change above.
Example oops seen prior to this patch:
$ echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/sriov_numvfs
Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc0000000004a6018
Oops: Kernel access of bad area, sig: 11 [#1]
LE SMP NR_CPUS=2048 NUMA PowerNV
CPU: 46 PID: 7006 Comm: bash Not tainted 4.15-ish
NIP: c0000000004a6018 LR: c0000000004a6014 CTR: 0000000000000000
REGS: c000008fc876b400 TRAP: 0300 Not tainted (4.15-ish)
MSR: 900000000280b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>
CFAR: c000000000d0be20 DAR: 0000000000000030 DSISR: 40000000 SOFTE: 1
...
NIP sysfs_do_create_link_sd.isra.0+0x68/0x150
LR sysfs_do_create_link_sd.isra.0+0x64/0x150
Call Trace:
pci_dev_type+0x0/0x30 (unreliable)
iommu_group_add_device+0x8c/0x600
iommu_add_device+0xe8/0x180
pnv_tce_iommu_bus_notifier+0xb0/0xf0
notifier_call_chain+0x9c/0x110
blocking_notifier_call_chain+0x64/0xa0
device_add+0x524/0x7d0
pci_device_add+0x248/0x450
pci_iov_add_virtfn+0x294/0x3e0
pci_enable_sriov+0x43c/0x580
mlx5_core_sriov_configure+0x15c/0x2f0 [mlx5_core]
sriov_numvfs_store+0x180/0x240
dev_attr_store+0x3c/0x60
sysfs_kf_write+0x64/0x90
kernfs_fop_write+0x1ac/0x240
__vfs_write+0x3c/0x70
vfs_write+0xd8/0x220
SyS_write+0x6c/0x110
system_call+0x58/0x6c
Fixes: 0bd971676e68 ("powerpc/powernv/npu: Add compound IOMMU groups")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reported-by: Santwana Samantray <santwana.samantray@in.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull keys fixes from James Morris:
"Two fixes from Eric Biggers"
* 'fixes-v5.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
KEYS: always initialize keyring_index_key::desc_len
KEYS: user: Align the payload buffer
Up to 4.12, __scsi_error_from_host_byte() would reset the host byte to
DID_OK for various cases including DID_NEXUS_FAILURE. Commit
2a842acab109 ("block: introduce new block status code type") replaced this
function with scsi_result_to_blk_status() and removed the host-byte
resetting code for the DID_NEXUS_FAILURE case. As the line
set_host_byte(cmd, DID_OK) was preserved for the other cases, I suppose
this was an editing mistake.
The fact that the host byte remains set after 4.13 is causing problems with
the sg_persist tool, which now returns success rather then exit status 24
when a RESERVATION CONFLICT error is encountered.
Fixes: 2a842acab109 "block: introduce new block status code type"
Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In v4.20 we changed our pgd/pud_present() to check for _PAGE_PRESENT
rather than just checking that the value is non-zero, e.g.:
static inline int pgd_present(pgd_t pgd)
{
- return !pgd_none(pgd);
+ return (pgd_raw(pgd) & cpu_to_be64(_PAGE_PRESENT));
}
Unfortunately this is broken on big endian, as the result of the
bitwise & is truncated to int, which is always zero because
_PAGE_PRESENT is 0x8000000000000000ul. This means pgd_present() and
pud_present() are always false at compile time, and the compiler
elides the subsequent code.
Remarkably with that bug present we are still able to boot and run
with few noticeable effects. However under some work loads we are able
to trigger a warning in the ext4 code:
WARNING: CPU: 11 PID: 29593 at fs/ext4/inode.c:3927 .ext4_set_page_dirty+0x70/0xb0
CPU: 11 PID: 29593 Comm: debugedit Not tainted 4.20.0-rc1 #1
...
NIP .ext4_set_page_dirty+0x70/0xb0
LR .set_page_dirty+0xa0/0x150
Call Trace:
.set_page_dirty+0xa0/0x150
.unmap_page_range+0xbf0/0xe10
.unmap_vmas+0x84/0x130
.unmap_region+0xe8/0x190
.__do_munmap+0x2f0/0x510
.__vm_munmap+0x80/0x110
.__se_sys_munmap+0x14/0x30
system_call+0x5c/0x70
The fix is simple, we need to convert the result of the bitwise & to
an int before returning it.
Thanks to Erhard, Jan Kara and Aneesh for help with debugging.
Fixes: da7ad366b497 ("powerpc/mm/book3s: Update pmd_present to look at _PAGE_PRESENT bit")
Cc: stable@vger.kernel.org # v4.20+
Reported-by: Erhard F. <erhard_f@mailbox.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull power management fixes from Rafael Wysocki:
"These fix a regression in the PM-runtime framework introduced by the
recent switch-over of it to using hrtimers and a use-after-free
introduced by one of the recent changes in the scmi-cpufreq driver.
Specifics:
- Use hrtimer_try_to_cancel() instead of hrtimer_cancel() in the
PM-runtime framework to avoid a possible timer-related deadlock
introduced recently (Vincent Guittot).
- Reorder the scmi-cpufreq driver code to avoid accessing memory that
has just been freed (Yangtao Li)"
* tag 'pm-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM-runtime: Fix deadlock when canceling hrtimer
cpufreq: scmi: Fix use-after-free in scmi_cpufreq_exit()
syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
called from construct_alloc_key() during sys_request_key(), because the
length of the key description was never calculated.
The problem is that we rely on ->desc_len being initialized by
search_process_keyrings(), specifically by search_nested_keyrings().
But, if the process isn't subscribed to any keyrings that never happens.
Fix it by always initializing keyring_index_key::desc_len as soon as the
description is set, like we already do in some places.
The following program reproduces the BUG_ON() when it's run as root and
no session keyring has been installed. If it doesn't work, try removing
pam_keyinit.so from /etc/pam.d/login and rebooting.
#include <stdlib.h>
#include <unistd.h>
#include <keyutils.h>
int main(void)
{
int id = add_key("keyring", "syz", NULL, 0, KEY_SPEC_USER_KEYRING);
keyctl_setperm(id, KEY_OTH_WRITE);
setreuid(5000, 5000);
request_key("user", "desc", "", id);
}
Reported-by: syzbot+ec24e95ea483de0a24da@syzkaller.appspotmail.com
Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.morris@microsoft.com>
The sysfs phy_identifier attribute for a sas_end_device comes from the rphy
phy_identifier value.
Currently this is not being set for rphys with an end device attached, so
we see incorrect symlinks from systemd disk/by-path:
root@localhost:~# ls -l /dev/disk/by-path/
total 0
lrwxrwxrwx 1 root root 9 Feb 13 12:26 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy0-lun-0 -> ../../sdb
lrwxrwxrwx 1 root root 10 Feb 13 12:26 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy0-lun-0-part1 -> ../../sdb1
lrwxrwxrwx 1 root root 10 Feb 13 12:26 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy0-lun-0-part2 -> ../../sdb2
lrwxrwxrwx 1 root root 10 Feb 13 12:26 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy0-lun-0-part3 -> ../../sdc3
Indeed, each sas_end_device phy_identifier value is 0:
root@localhost:/# more sys/class/sas_device/end_device-0\:0\:2/phy_identifier
0
root@localhost:/# more sys/class/sas_device/end_device-0\:0\:10/phy_identifier
0
This patch fixes the discovery code to set the phy_identifier. With this,
we now get proper symlinks:
root@localhost:~# ls -l /dev/disk/by-path/
total 0
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy10-lun-0 -> ../../sdg
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy11-lun-0 -> ../../sdh
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy2-lun-0 -> ../../sda
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy2-lun-0-part1 -> ../../sda1
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy3-lun-0 -> ../../sdb
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy3-lun-0-part1 -> ../../sdb1
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy3-lun-0-part2 -> ../../sdb2
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy4-lun-0 -> ../../sdc
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy4-lun-0-part1 -> ../../sdc1
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy4-lun-0-part2 -> ../../sdc2
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy4-lun-0-part3 -> ../../sdc3
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy5-lun-0 -> ../../sdd
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy7-lun-0 -> ../../sde
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy7-lun-0-part1 -> ../../sde1
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy7-lun-0-part2 -> ../../sde2
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy7-lun-0-part3 -> ../../sde3
lrwxrwxrwx 1 root root 9 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy8-lun-0 -> ../../sdf
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy8-lun-0-part1 -> ../../sdf1
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy8-lun-0-part2 -> ../../sdf2
lrwxrwxrwx 1 root root 10 Feb 13 11:53 platform-HISI0162:01-sas-exp0x500e004aaaaaaa1f-phy8-lun-0-part3 -> ../../sdf3
Fixes: 2908d778ab3e ("[SCSI] aic94xx: new driver")
Reported-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Tested-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When binding an SCM volume to a physical address the hypervisor has the
option to return early with a continue token with the expectation that
the guest will resume the bind operation until it completes. A quirk of
this interface is that the bind address will only be returned by the
first bind h-call and the subsequent calls will return
0xFFFF_FFFF_FFFF_FFFF for the bind address.
We currently do not save the address returned by the first h-call. As a
result we will use the junk address as the base of the bound region if
the hypervisor decides to split the bind across multiple h-calls. This
bug was found when testing with very large SCM volumes where the bind
process would take more time than they hypervisor's internal h-call time
limit would allow. This patch fixes the issue by saving the bind address
from the first call.
Cc: stable@vger.kernel.org
Fixes: b5beae5e224f ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull ARM SoC fixes from Arnd Bergmann:
"Only a handful of device tree fixes, all simple enough:
NVIDIA Tegra:
- Fix a regression for booting on chromebooks
TI OMAP:
- Two fixes PHY mode on am335x reference boards
Marvell mvebu:
- A regression fix for Armada XP NAND flash controllers
- An incorrect reset signal on the clearfog board"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
ARM: tegra: Restore DT ABI on Tegra124 Chromebooks
ARM: dts: am335x-evm: Fix PHY mode for ethernet
ARM: dts: am335x-evmsk: Fix PHY mode for ethernet
arm64: dts: clearfog-gt-8k: fix SGMII PHY reset signal
ARM: dts: armada-xp: fix Armada XP boards NAND description
* pm-cpufreq-fixes:
cpufreq: scmi: Fix use-after-free in scmi_cpufreq_exit()
Align the payload of "user" and "logon" keys so that users of the
keyrings service can access it as a struct that requires more than
2-byte alignment. fscrypt currently does this which results in the read
of fscrypt_key::size being misaligned as it needs 4-byte alignment.
Align to __alignof__(u64) rather than __alignof__(long) since in the
future it's conceivable that people would use structs beginning with
u64, which on some platforms would require more than 'long' alignment.
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Fixes: 2aa349f6e37c ("[PATCH] Keys: Export user-defined keyring operations")
Fixes: 88bd6ccdcdd6 ("ext4 crypto: add encryption key management facilities")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
The function sd_zbc_do_report_zones() issues a REPORT ZONES command with a
buffer size calculated based on the number of zones requested by the
caller. This value should however not exceed the capabilities of the
hardware maximum command size, that is, should not exceed the
max_hw_sectors limit of the device. This problem leads to failures of
report zones commands when re-validating disks with some SAS HBAs.
Fix this by limiting a report zone command buffer size to the minimum of
the device max_hw_sectors and calculated value based on the requested
number of zones. This does not change the semantic of the report_zones file
operation as report zones can always return less zone reports than
requested. Short reports are handled using a loop execution of the
report_zones file operation in the function blk_report_zones().
[Damien]
Before patch 'e76239a3748c ("block: add a report_zones method")', report
zones buffer allocation was limited to max_sectors when allocated in
blk_report_zones(). This however does not consider the actual format of the
device reply which is interface dependent. Limiting the allocation based
on the size of the expected reply format rather than the size of the array
of generic sturct blkzone passed by blk_report_zones() makes more sense.
Fixes: e76239a3748c ("block: add a report_zones method")
Cc: stable@vger.kernel.org
Signed-off-by: Masato Suzuki <masato.suzuki@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>