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Linux kernel
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Platform device helper routines won't update the NUMA distance table
while creating a platform device, even if the device is present on a
NUMA node that doesn't have memory or CPU. This is especially true for
pmem devices. If the target node of the pmem device is not online, we
find the nearest online node to the device and associate the pmem device
with that online node. To find the nearest online node, we should have
the numa distance table updated correctly. Update the distance
information during the device probe.
For a papr scm device on NUMA node 3 distance_lookup_table value for
distance_ref_points_depth = 2 before and after fix is below:
Before fix:
node 3 distance depth 0 - 0
node 3 distance depth 1 - 0
node 4 distance depth 0 - 4
node 4 distance depth 1 - 2
node 5 distance depth 0 - 5
node 5 distance depth 1 - 1
After fix
node 3 distance depth 0 - 3
node 3 distance depth 1 - 1
node 4 distance depth 0 - 4
node 4 distance depth 1 - 2
node 5 distance depth 0 - 5
node 5 distance depth 1 - 1
Without the fix, the nearest numa node to the pmem device (NUMA node 3)
will be picked as 4. After the fix, we get the correct numa node which
is 5.
Fixes: da1115fdbd6e ("powerpc/nvdimm: Pick nearby online node if the device node is not online")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230404041433.1781804-1-aneesh.kumar@linux.ibm.com
The hypervisor supports user-mode NX from Power10.
pseries_vas_dlpar_cpu() is called from lparcfg_write() to update VAS
windows for DLPAR event in shared processor mode and the kernel gets
-ENOTSUPP for HCALLs if the user-mode NX is not supported. The current
VAS implementation also supports only with Radix page tables. Whereas in
dedicated processor mode, pseries_vas_notifier() is registered only if
the copy/paste feature is enabled. So instead of displaying HCALL error
messages, update VAS capabilities if the copy/paste feature is
available.
This patch ignores updating VAS capabilities in pseries_vas_dlpar_cpu()
and returns success if the copy/paste feature is not enabled. Then
lparcfg_write() completes the processor DLPAR operations without any
failures.
Fixes: 2147783d6bf0 ("powerpc/pseries: Use lparcfg to reconfig VAS windows for DLPAR CPU")
Cc: stable@vger.kernel.org # v6.1+
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/1d0e727e7dbd9a28627ef08ca9df9c86a50175e2.camel@linux.ibm.com
powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which
from my (arguably very short) checking is not commonly done for other
archs. This is fine, except when PF_IO_WORKER's have been created and
the task does something that causes a coredump to be generated. Then we
get this crash:
Kernel attempted to read user page (160) - exploit attempt? (uid: 1000)
BUG: Kernel NULL pointer dereference on read at 0x00000160
Faulting instruction address: 0xc0000000000c3a60
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries
Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod
CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88
Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries
NIP: c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0
REGS: c0000000041833b0 TRAP: 0300 Not tainted (6.3.0-rc2+)
MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 88082828 XER: 200400f8
...
NIP memcpy_power7+0x200/0x7d0
LR ppr_get+0x64/0xb0
Call Trace:
ppr_get+0x40/0xb0 (unreliable)
__regset_get+0x180/0x1f0
regset_get_alloc+0x64/0x90
elf_core_dump+0xb98/0x1b60
do_coredump+0x1c34/0x24a0
get_signal+0x71c/0x1410
do_notify_resume+0x140/0x6f0
interrupt_exit_user_prepare_main+0x29c/0x320
interrupt_exit_user_prepare+0x6c/0xa0
interrupt_return_srr_user+0x8/0x138
Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL
pt_regs.
Check for a valid pt_regs in both ppc_get/ppr_set, and return an error
if not set. The actual error value doesn't seem to be important here, so
just pick -EINVAL.
Fixes: fa439810cc1b ("powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[mpe: Trim oops in change log, add Fixes & Cc stable]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/d9f63344-fe7c-56ae-b420-4a1a04a2ae4c@kernel.dk
Userspace PROT_NONE ptes set _PAGE_PRIVILEGED, triggering a false
positive debug assertion that __pte_flags_need_flush() is not called
on a kernel mapping.
Detect when it is a userspace PROT_NONE page by checking the required
bits of PAGE_NONE are set, and none of the RWX bits are set.
pte_protnone() is insufficient here because it always returns 0 when
CONFIG_NUMA_BALANCING=n.
Fixes: b11931e9adc1 ("powerpc/64s: add pte_needs_flush and huge_pmd_needs_flush")
Cc: stable@vger.kernel.org # v6.1+
Reported-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230302225947.81083-1-bgray@linux.ibm.com
To support detection of read faults with Radix execute-only memory, the
vma_is_accessible() check in access_error() (which checks for PROT_NONE)
was replaced with a check to see if VM_READ was missing, and if so,
returns true to assert the fault was caused by a bad read.
This is incorrect, as it ignores that both VM_WRITE and VM_EXEC imply
read on powerpc, as defined in protection_map[]. This causes mappings
containing VM_WRITE or VM_EXEC without VM_READ to misreport the cause of
page faults, since the MMU is still allowing reads.
Correct this by restoring the original vma_is_accessible() check for
PROT_NONE mappings, and adding a separate check for Radix PROT_EXEC-only
mappings.
Fixes: 395cac7752b9 ("powerpc/mm: Support execute-only memory on the Radix MMU")
Reported-by: Michal Suchánek <msuchanek@suse.de>
Link: https://lore.kernel.org/r/20230308152702.GR19419@kitsune.suse.cz
Tested-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230310050834.63105-1-ruscur@russell.cc
The RTAS work area allocator uses code that is built by
GENERIC_ALLOCATOR, so the PSERIES Kconfig should select the
required Kconfig symbol to fix multiple build errors.
powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o: in function `.rtas_work_area_allocator_init':
rtas-work-area.c:(.init.text+0x288): undefined reference to `.gen_pool_create'
powerpc64-linux-ld: rtas-work-area.c:(.init.text+0x2dc): undefined reference to `.gen_pool_set_algo'
powerpc64-linux-ld: rtas-work-area.c:(.init.text+0x310): undefined reference to `.gen_pool_add_owner'
powerpc64-linux-ld: rtas-work-area.c:(.init.text+0x43c): undefined reference to `.gen_pool_destroy'
powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o:(.toc+0x0): undefined reference to `gen_pool_first_fit_order_align'
powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o: in function `.__rtas_work_area_alloc':
rtas-work-area.c:(.ref.text+0x14c): undefined reference to `.gen_pool_alloc_algo_owner'
powerpc64-linux-ld: rtas-work-area.c:(.ref.text+0x238): undefined reference to `.gen_pool_alloc_algo_owner'
powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o: in function `.rtas_work_area_free':
rtas-work-area.c:(.ref.text+0x44c): undefined reference to `.gen_pool_free_owner'
Fixes: 43033bc62d34 ("powerpc/pseries: add RTAS work area allocator")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230223070116.660-2-rdunlap@infradead.org
This reverts part of commit 015b8cc5e7c4 ("wifi: cfg80211: Fix use after
free for wext")
This commit broke WPA offload by unconditionally clearing the crypto
modes for non-WEP connections. Drop that part of the patch.
Signed-off-by: Hector Martin <marcan@marcan.st>
Reported-by: Ilya <me@0upti.me>
Reported-and-tested-by: Janne Grunau <j@jannau.net>
Reviewed-by: Eric Curtin <ecurtin@redhat.com>
Fixes: 015b8cc5e7c4 ("wifi: cfg80211: Fix use after free for wext")
Cc: stable@kernel.org
Link: https://lore.kernel.org/linux-wireless/ZAx0TWRBlGfv7pNl@kroah.com/T/#m11e6e0915ab8fa19ce8bc9695ab288c0fe018edf
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull tpm fixes from Jarkko Sakkinen:
"Two additional bug fixes for v6.3"
* tag 'tpm-v6.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
tpm: disable hwrng for fTPM on some AMD designs
tpm/eventlog: Don't abort tpm_read_log on faulty ACPI address
Pull xfs fixes from Darrick Wong:
- Fix a crash if mount time quotacheck fails when there are inodes
queued for garbage collection.
- Fix an off by one error when discarding folios after writeback
failure.
* tag 'xfs-6.3-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix off-by-one-block in xfs_discard_folio()
xfs: quotacheck failure can race with background inode inactivation
AMD has issued an advisory indicating that having fTPM enabled in
BIOS can cause "stuttering" in the OS. This issue has been fixed
in newer versions of the fTPM firmware, but it's up to system
designers to decide whether to distribute it.
This issue has existed for a while, but is more prevalent starting
with kernel 6.1 because commit b006c439d58db ("hwrng: core - start
hwrng kthread also for untrusted sources") started to use the fTPM
for hwrng by default. However, all uses of /dev/hwrng result in
unacceptable stuttering.
So, simply disable registration of the defective hwrng when detecting
these faulty fTPM versions. As this is caused by faulty firmware, it
is plausible that such a problem could also be reproduced by other TPM
interactions, but this hasn't been shown by any user's testing or reports.
It is hypothesized to be triggered more frequently by the use of the RNG
because userspace software will fetch random numbers regularly.
Intentionally continue to register other TPM functionality so that users
that rely upon PCR measurements or any storage of data will still have
access to it. If it's found later that another TPM functionality is
exacerbating this problem a module parameter it can be turned off entirely
and a module parameter can be introduced to allow users who rely upon
fTPM functionality to turn it on even though this problem is present.
Link: https://www.amd.com/en/support/kb/faq/pa-410
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216989
Link: https://lore.kernel.org/all/20230209153120.261904-1-Jason@zx2c4.com/
Fixes: b006c439d58d ("hwrng: core - start hwrng kthread also for untrusted sources")
Cc: stable@vger.kernel.org
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Tested-by: reach622@mailcuk.com
Tested-by: Bell <1138267643@qq.com>
Co-developed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Pull staging driver fixes and removal from Greg KH:
"Here are four small staging driver fixes, and one big staging driver
deletion for 6.3-rc2.
The fixes are:
- rtl8192e driver fixes for where the driver was attempting to
execute various programs directly from the disk for unknown reasons
- rtl8723bs driver fixes for issues found by Hans in testing
The deleted driver is the removal of the r8188eu wireless driver as
now in 6.3-rc1 we have a "real" wifi driver for one that includes
support for many many more devices than this old driver did. So it's
time to remove it as it is no longer needed. The maintainers of this
driver all have acked its removal. Many thanks to them over the years
for working to clean it up and keep it working while the real driver
was being developed.
All of these have been in linux-next this week with no reported
problems"
* tag 'staging-6.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: r8188eu: delete driver
staging: rtl8723bs: Pass correct parameters to cfg80211_get_bss()
staging: rtl8723bs: Fix key-store index handling
staging: rtl8192e: Remove call_usermodehelper starting RadioPower.sh
staging: rtl8192e: Remove function ..dm_check_ac_dc_power calling a script
The recent writeback corruption fixes changed the code in
xfs_discard_folio() to calculate a byte range to for punching
delalloc extents. A mistake was made in using round_up(pos) for the
end offset, because when pos points at the first byte of a block, it
does not get rounded up to point to the end byte of the block. hence
the punch range is short, and this leads to unexpected behaviour in
certain cases in xfs_bmap_punch_delalloc_range.
e.g. pos = 0 means we call xfs_bmap_punch_delalloc_range(0,0), so
there is no previous extent and it rounds up the punch to the end of
the delalloc extent it found at offset 0, not the end of the range
given to xfs_bmap_punch_delalloc_range().
Fix this by handling the zero block offset case correctly.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=217030
Link: https://lore.kernel.org/linux-xfs/Y+vOfaxIWX1c%2Fyy9@bfoster/
Fixes: 7348b322332d ("xfs: xfs_bmap_punch_delalloc_range() should take a byte range")
Reported-by: Pengfei Xu <pengfei.xu@intel.com>
Found-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
tpm_read_log_acpi() should return -ENODEV when no eventlog from the ACPI
table is found. If the firmware vendor includes an invalid log address
we are unable to map from the ACPI memory and tpm_read_log() returns -EIO
which would abort discovery of the eventlog.
Change the return value from -EIO to -ENODEV when acpi_os_map_iomem()
fails to map the event log.
The following hardware was used to test this issue:
Framework Laptop (Pre-production)
BIOS: INSYDE Corp, Revision: 3.2
TPM Device: NTC, Firmware Revision: 7.2
Dump of the faulty ACPI TPM2 table:
[000h 0000 4] Signature : "TPM2" [Trusted Platform Module hardware interface Table]
[004h 0004 4] Table Length : 0000004C
[008h 0008 1] Revision : 04
[009h 0009 1] Checksum : 2B
[00Ah 0010 6] Oem ID : "INSYDE"
[010h 0016 8] Oem Table ID : "TGL-ULT"
[018h 0024 4] Oem Revision : 00000002
[01Ch 0028 4] Asl Compiler ID : "ACPI"
[020h 0032 4] Asl Compiler Revision : 00040000
[024h 0036 2] Platform Class : 0000
[026h 0038 2] Reserved : 0000
[028h 0040 8] Control Address : 0000000000000000
[030h 0048 4] Start Method : 06 [Memory Mapped I/O]
[034h 0052 12] Method Parameters : 00 00 00 00 00 00 00 00 00 00 00 00
[040h 0064 4] Minimum Log Length : 00010000
[044h 0068 8] Log Address : 000000004053D000
Fixes: 0cf577a03f21 ("tpm: Fix handling of missing event log")
Tested-by: Erkki Eilonen <erkki@bearmetal.eu>
Signed-off-by: Morten Linderud <morten@linderud.pw>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Pull x86 fix from Borislav Petkov:
"A single erratum fix for AMD machines:
- Disable XSAVES on AMD Zen1 and Zen2 machines due to an erratum. No
impact to anything as those machines will fallback to XSAVEC which
is equivalent there"
* tag 'x86_urgent_for_v6.3_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU/AMD: Disable XSAVES on AMD family 0x17
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