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Linux kernel
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Currently building the powerpc selftests with USERCFLAGS set to anything
causes the build to break:
$ make -C tools/testing/selftests/powerpc V=1 USERCFLAGS=-Wno-error
...
gcc -Wno-error cache_shape.c ...
cache_shape.c:18:10: fatal error: utils.h: No such file or directory
18 | #include "utils.h"
| ^~~~~~~~~
compilation terminated.
This happens because the USERCFLAGS are added to CFLAGS in lib.mk, which
causes the check of CFLAGS in powerpc/flags.mk to skip setting CFLAGS at
all, resulting in none of the usual CFLAGS being passed. That can
be seen in the output above, the only flag passed to the compiler is
-Wno-error.
Fix it by dropping the conditional setting of CFLAGS in flags.mk.
Instead always set CFLAGS, but also append USERCFLAGS if they are set.
Note that appending to CFLAGS (with +=) wouldn't work, because flags.mk
is included by multiple Makefiles (to support partial builds), causing
CFLAGS to be appended to multiple times. Additionally that would place
the USERCFLAGS prior to the standard CFLAGS, meaning the USERCFLAGS
couldn't override the standard flags. Being able to override the
standard flags is desirable, for example for adding -Wno-error.
With the fix in place, the CFLAGS are set correctly, including the
USERCFLAGS:
$ make -C tools/testing/selftests/powerpc V=1 USERCFLAGS=-Wno-error
...
gcc -std=gnu99 -O2 -Wall -Werror -DGIT_VERSION='"v6.10-rc2-7-gdea17e7e56c3"'
-I/home/michael/linux/tools/testing/selftests/powerpc/include -Wno-error
cache_shape.c ...
Fixes: 5553a79387e9 ("selftests/powerpc: Add flags.mk to support pmu buildable")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240706120833.909853-1-mpe@ellerman.id.au
kexec on pseries disables AIL (reloc_on_exc), required for scv
instruction support, before other CPUs have been shut down. This means
they can execute scv instructions after AIL is disabled, which causes an
interrupt at an unexpected entry location that crashes the kernel.
Change the kexec sequence to disable AIL after other CPUs have been
brought down.
As a refresher, the real-mode scv interrupt vector is 0x17000, and the
fixed-location head code probably couldn't easily deal with implementing
such high addresses so it was just decided not to support that interrupt
at all.
Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Closes: https://lore.kernel.org/3b4b2943-49ad-4619-b195-bc416f1d1409@linux.ibm.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Gautam Menghani <gautam@linux.ibm.com>
Tested-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Link: https://msgid.link/20240625134047.298759-1-npiggin@gmail.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If a PCI device is removed during eeh_pe_report_edev(), edev->pdev
will change and can cause a crash, hold the PCI rescan/remove lock
while taking a copy of edev->pdev->bus.
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240617140240.580453-1-ganeshgr@linux.ibm.com
Reading the dispatch trace log from /sys/kernel/debug/powerpc/dtl/cpu-*
results in a BUG() when the config CONFIG_HARDENED_USERCOPY is enabled as
shown below.
kernel BUG at mm/usercopy.c:102!
Oops: Exception in kernel mode, sig: 5 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: xfs libcrc32c dm_service_time sd_mod t10_pi sg ibmvfc
scsi_transport_fc ibmveth pseries_wdt dm_multipath dm_mirror dm_region_hash dm_log dm_mod fuse
CPU: 27 PID: 1815 Comm: python3 Not tainted 6.10.0-rc3 #85
Hardware name: IBM,9040-MRX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_042) hv:phyp pSeries
NIP: c0000000005d23d4 LR: c0000000005d23d0 CTR: 00000000006ee6f8
REGS: c000000120c078c0 TRAP: 0700 Not tainted (6.10.0-rc3)
MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 2828220f XER: 0000000e
CFAR: c0000000001fdc80 IRQMASK: 0
[ ... GPRs omitted ... ]
NIP [c0000000005d23d4] usercopy_abort+0x78/0xb0
LR [c0000000005d23d0] usercopy_abort+0x74/0xb0
Call Trace:
usercopy_abort+0x74/0xb0 (unreliable)
__check_heap_object+0xf8/0x120
check_heap_object+0x218/0x240
__check_object_size+0x84/0x1a4
dtl_file_read+0x17c/0x2c4
full_proxy_read+0x8c/0x110
vfs_read+0xdc/0x3a0
ksys_read+0x84/0x144
system_call_exception+0x124/0x330
system_call_vectored_common+0x15c/0x2ec
--- interrupt: 3000 at 0x7fff81f3ab34
Commit 6d07d1cd300f ("usercopy: Restrict non-usercopy caches to size 0")
requires that only whitelisted areas in slab/slub objects can be copied to
userspace when usercopy hardening is enabled using CONFIG_HARDENED_USERCOPY.
Dtl contains hypervisor dispatch events which are expected to be read by
privileged users. Hence mark this safe for user access.
Specify useroffset=0 and usersize=DISPATCH_LOG_BYTES to whitelist the
entire object.
Co-developed-by: Vishal Chourasia <vishalc@linux.ibm.com>
Signed-off-by: Vishal Chourasia <vishalc@linux.ibm.com>
Signed-off-by: Anjali K <anjalik@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240614173844.746818-1-anjalik@linux.ibm.com
According to the code logic, when the kernel is loaded at address 0, no
copying operation should be performed, but it is currently being done.
This patch fixes the issue where the kernel code was incorrectly
duplicated to address 0 when booting from address 0.
Fixes: b270bebd34e3 ("powerpc/64s: Run at the kernel virtual address earlier in boot")
Cc: stable@vger.kernel.org # v6.4+
Signed-off-by: Jinglin Wen <jinglin.wen@shingroup.cn>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240620024150.14857-1-jinglin.wen@shingroup.cn
Al reported a possible use-after-free (UAF) in kvm_spapr_tce_attach_iommu_group().
It looks up `stt` from tablefd, but then continues to use it after doing
fdput() on the returned fd. After the fdput() the tablefd is free to be
closed by another thread. The close calls kvm_spapr_tce_release() and
then release_spapr_tce_table() (via call_rcu()) which frees `stt`.
Although there are calls to rcu_read_lock() in
kvm_spapr_tce_attach_iommu_group() they are not sufficient to prevent
the UAF, because `stt` is used outside the locked regions.
With an artifcial delay after the fdput() and a userspace program which
triggers the race, KASAN detects the UAF:
BUG: KASAN: slab-use-after-free in kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]
Read of size 4 at addr c000200027552c30 by task kvm-vfio/2505
CPU: 54 PID: 2505 Comm: kvm-vfio Not tainted 6.10.0-rc3-next-20240612-dirty #1
Hardware name: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35-g1851b2a06 PowerNV
Call Trace:
dump_stack_lvl+0xb4/0x108 (unreliable)
print_report+0x2b4/0x6ec
kasan_report+0x118/0x2b0
__asan_load4+0xb8/0xd0
kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]
kvm_vfio_set_attr+0x524/0xac0 [kvm]
kvm_device_ioctl+0x144/0x240 [kvm]
sys_ioctl+0x62c/0x1810
system_call_exception+0x190/0x440
system_call_vectored_common+0x15c/0x2ec
...
Freed by task 0:
...
kfree+0xec/0x3e0
release_spapr_tce_table+0xd4/0x11c [kvm]
rcu_core+0x568/0x16a0
handle_softirqs+0x23c/0x920
do_softirq_own_stack+0x6c/0x90
do_softirq_own_stack+0x58/0x90
__irq_exit_rcu+0x218/0x2d0
irq_exit+0x30/0x80
arch_local_irq_restore+0x128/0x230
arch_local_irq_enable+0x1c/0x30
cpuidle_enter_state+0x134/0x5cc
cpuidle_enter+0x6c/0xb0
call_cpuidle+0x7c/0x100
do_idle+0x394/0x410
cpu_startup_entry+0x60/0x70
start_secondary+0x3fc/0x410
start_secondary_prolog+0x10/0x14
Fix it by delaying the fdput() until `stt` is no longer in use, which
is effectively the entire function. To keep the patch minimal add a call
to fdput() at each of the existing return paths. Future work can convert
the function to goto or __cleanup style cleanup.
With the fix in place the test case no longer triggers the UAF.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Closes: https://lore.kernel.org/all/20240610024437.GA1464458@ZenIV/
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240614122910.3499489-1-mpe@ellerman.id.au
Looks like drivers/crypto/vmx/.gitignore should have been merged into
arch/powerpc/crypto/.gitignore as part of commit
109303336a0c ("crypto: vmx - Move to arch/powerpc/crypto") so that all
generated asm files are ignored.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Fixes: 109303336a0c ("crypto: vmx - Move to arch/powerpc/crypto")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240603-powerpc-crypto-ignore-p8-asm-v1-1-05843fec2bb7@linux.ibm.com
Pull ata fixes from Niklas Cassel:
- Add a quirk for three different devices that have shown issues with
LPM (link power management). These devices appear to not implement
LPM properly, since we see command timeouts when enabling LPM. The
quirk disables LPM for these problematic devices. (Me)
- Do not apply the Intel PCS quirk on Alder Lake. The quirk is not
needed and was originally added by mistake when LPM support was
enabled for this AHCI controller. Enabling the quirk when not needed
causes the the controller to not be able to detect the connected
devices on some platforms.
* tag 'ata-6.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
ata: libata-core: Add ATA_HORKAGE_NOLPM for Apacer AS340
ata: libata-core: Add ATA_HORKAGE_NOLPM for AMD Radeon S3 SSD
ata: libata-core: Add ATA_HORKAGE_NOLPM for Crucial CT240BX500SSD1
ata: ahci: Do not apply Intel PCS quirk on Intel Alder Lake
Pull x86 fixes from Ingo Molnar:
"Miscellaneous topology parsing fixes:
- Fix topology parsing regression on older CPUs in the new AMD/Hygon
parser
- Fix boot crash on odd Intel Quark and similar CPUs that do not fill
out cpuinfo_x86::x86_clflush_size and zero out
cpuinfo_x86::x86_cache_alignment as a result.
Provide 32 bytes as a general fallback value.
- Fix topology enumeration on certain rare CPUs where the BIOS locks
certain CPUID leaves and the kernel unlocked them late, which broke
with the new topology parsing code. Factor out this unlocking logic
and move it earlier in the parsing sequence"
* tag 'x86-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology/intel: Unlock CPUID before evaluating anything
x86/cpu: Provide default cache line size if not enumerated
x86/topology/amd: Evaluate SMT in CPUID leaf 0x8000001e only on family 0x17 and greater
Commit 7627a0edef54 ("ata: ahci: Drop low power policy board type")
dropped the board_ahci_low_power board type, and instead enables LPM if:
-The AHCI controller reports that it supports LPM (Partial/Slumber), and
-CONFIG_SATA_MOBILE_LPM_POLICY != 0, and
-The port is not defined as external in the per port PxCMD register, and
-The port is not defined as hotplug capable in the per port PxCMD
register.
Partial and Slumber LPM states can either be initiated by HIPM or DIPM.
For HIPM (host initiated power management) to get enabled, both the AHCI
controller and the drive have to report that they support HIPM.
For DIPM (device initiated power management) to get enabled, only the
drive has to report that it supports DIPM. However, the HBA will reject
device requests to enter LPM states which the HBA does not support.
The problem is that Apacer AS340 drives do not handle low power modes
correctly. The problem was most likely not seen before because no one
had used this drive with a AHCI controller with LPM enabled.
Add a quirk so that we do not enable LPM for this drive, since we see
command timeouts if we do (even though the drive claims to support DIPM).
Fixes: 7627a0edef54 ("ata: ahci: Drop low power policy board type")
Cc: stable@vger.kernel.org
Reported-by: Tim Teichmann <teichmanntim@outlook.de>
Closes: https://lore.kernel.org/linux-ide/87bk4pbve8.ffs@tglx/
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Pull scheduler fix from Ingo Molnar:
"Export a symbol to make life easier for instrumentation/debugging"
* tag 'sched-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/x86: Export 'percpu arch_freq_scale'
Intel CPUs have a MSR bit to limit CPUID enumeration to leaf two. If
this bit is set by the BIOS then CPUID evaluation including topology
enumeration does not work correctly as the evaluation code does not try
to analyze any leaf greater than two.
This went unnoticed before because the original topology code just
repeated evaluation several times and managed to overwrite the initial
limited information with the correct one later. The new evaluation code
does it once and therefore ends up with the limited and wrong
information.
Cure this by unlocking CPUID right before evaluating anything which
depends on the maximum CPUID leaf being greater than two instead of
rereading stuff after unlock.
Fixes: 22d63660c35e ("x86/cpu: Use common topology code for Intel")
Reported-by: Peter Schneider <pschneider1968@googlemail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Peter Schneider <pschneider1968@googlemail.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/fd3f73dc-a86f-4bcf-9c60-43556a21eb42@googlemail.com
Commit 7627a0edef54 ("ata: ahci: Drop low power policy board type")
dropped the board_ahci_low_power board type, and instead enables LPM if:
-The AHCI controller reports that it supports LPM (Partial/Slumber), and
-CONFIG_SATA_MOBILE_LPM_POLICY != 0, and
-The port is not defined as external in the per port PxCMD register, and
-The port is not defined as hotplug capable in the per port PxCMD
register.
Partial and Slumber LPM states can either be initiated by HIPM or DIPM.
For HIPM (host initiated power management) to get enabled, both the AHCI
controller and the drive have to report that they support HIPM.
For DIPM (device initiated power management) to get enabled, only the
drive has to report that it supports DIPM. However, the HBA will reject
device requests to enter LPM states which the HBA does not support.
The problem is that AMD Radeon S3 SSD drives do not handle low power modes
correctly. The problem was most likely not seen before because no one
had used this drive with a AHCI controller with LPM enabled.
Add a quirk so that we do not enable LPM for this drive, since we see
command timeouts if we do (even though the drive claims to support both
HIPM and DIPM).
Fixes: 7627a0edef54 ("ata: ahci: Drop low power policy board type")
Cc: stable@vger.kernel.org
Reported-by: Doru Iorgulescu <doru.iorgulescu1@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218832
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Pull perf events fix from Ingo Molnar:
"Add missing MODULE_DESCRIPTION() lines"
* tag 'perf-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Add missing MODULE_DESCRIPTION() lines
perf/x86/rapl: Add missing MODULE_DESCRIPTION() line
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