When a vCPU is brought done, the XIVE VP (Virtual Processor) is first
disabled and then the event notification queues are freed. When freeing
the queues, we check for possible escalation interrupts and free them
also.
But when a XIVE VP is disabled, the underlying XIVE ENDs also are
disabled in OPAL. When an END (Event Notification Descriptor) is
disabled, its ESB pages (ESn and ESe) are disabled and loads return all
1s. Which means that any access on the ESB page of the escalation
interrupt will return invalid values.
When an interrupt is freed, the shutdown handler computes a 'saved_p'
field from the value returned by a load in xive_do_source_set_mask().
This value is incorrect for escalation interrupts for the reason
described above.
This has no impact on Linux/KVM today because we don't make use of it
but we will introduce in future changes a xive_get_irqchip_state()
handler. This handler will use the 'saved_p' field to return the state
of an interrupt and 'saved_p' being incorrect, softlockup will occur.
Fix the vCPU cleanup sequence by first freeing the escalation interrupts
if any, then disable the XIVE VP and last free the queues.
Fixes: 90c73795afa2 ("KVM: PPC: Book3S HV: Add a new KVM device for the XIVE native exploitation mode") Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190806172538.5087-1-clg@kaod.org Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
An oops can be triggered in the scheduler when running qemu on arm64:
Unable to handle kernel paging request at virtual address ffff000008effe40
Internal error: Oops: 96000007 [#1] SMP
Process migration/0 (pid: 12, stack limit = 0x00000000084e3736)
pstate: 20000085 (nzCv daIf -PAN -UAO)
pc : __ll_sc___cmpxchg_case_acq_4+0x4/0x20
lr : move_queued_task.isra.21+0x124/0x298
...
Call trace:
__ll_sc___cmpxchg_case_acq_4+0x4/0x20
__migrate_task+0xc8/0xe0
migration_cpu_stop+0x170/0x180
cpu_stopper_thread+0xec/0x178
smpboot_thread_fn+0x1ac/0x1e8
kthread+0x134/0x138
ret_from_fork+0x10/0x18
__set_cpus_allowed_ptr() will choose an active dest_cpu in affinity mask to
migrage the process if process is not currently running on any one of the
CPUs specified in affinity mask. __set_cpus_allowed_ptr() will choose an
invalid dest_cpu (dest_cpu >= nr_cpu_ids, 1024 in my virtual machine) if
CPUS in an affinity mask are deactived by cpu_down after cpumask_intersects
check. cpumask_test_cpu() of dest_cpu afterwards is overflown and may pass if
corresponding bit is coincidentally set. As a consequence, kernel will
access an invalid rq address associate with the invalid CPU in
migration_cpu_stop->__migrate_task->move_queued_task and the Oops occurs.
The reproduce the crash:
1) A process repeatedly binds itself to cpu0 and cpu1 in turn by calling
sched_setaffinity.
2) A shell script repeatedly does "echo 0 > /sys/devices/system/cpu/cpu1/online"
and "echo 1 > /sys/devices/system/cpu/cpu1/online" in turn.
3) Oops appears if the invalid CPU is set in memory after tested cpumask.
Signed-off-by: KeMeng Shi <shikemeng@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/1568616808-16808-1-git-send-email-shikemeng@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
thermal_zone_device_unregister() cancels the delayed work that polls the
thermal zone, but it does not wait for it to finish. This is racy with
respect to the freeing of the thermal zone device, which can result in a
use-after-free [1].
Fix this by waiting for the delayed work to finish before freeing the
thermal zone device. Note that thermal_zone_device_set_polling() is
never invoked from an atomic context, so it is safe to call
cancel_delayed_work_sync() that can block.
[1]
[ +0.002221] ==================================================================
[ +0.000064] BUG: KASAN: use-after-free in __mutex_lock+0x1076/0x11c0
[ +0.000016] Read of size 8 at addr ffff8881e48e0450 by task kworker/1:0/17
LPTimer can use a 32KHz clock for counting. It depends on clock tree
configuration. In such a case, PWM output frequency range is limited.
Although unlikely, nothing prevents user from requesting a PWM frequency
above counting clock (32KHz for instance):
- This causes (prd - 1) = 0xffff to be written in ARR register later in
the apply() routine.
This results in badly configured PWM period (and also duty_cycle).
Add a check to report an error is such a case.
IF the server rejected our layout return with a state error such as
NFS4ERR_BAD_STATEID, or even a stale inode error, then we do want
to clear out all the remaining layout segments and mark that stateid
as invalid.
Fixes: 1c5bd76d17cca ("pNFS: Enable layoutreturn operation for...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Do not try to allocate any amount of memory requested by the user.
Instead limit it to 128 registers. Actually the longest series of
consecutive allowed registers are 48, mmGB_TILE_MODE0-31 and
mmGB_MACROTILE_MODE0-15 (0x2644-0x2673).
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=111273 Signed-off-by: Trek <trek00@inbox.ru> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
... this works:
nft add rule ip filter input add @set1 { ip saddr }
-> whenever rule is triggered, the source ip address is inserted
into the set (if it did not exist).
This won't work:
nft add rule ip filter input ip saddr @set1 counter
Error: Could not process rule: Operation not supported
In other words, we can add entries to the set, but then can't make
matching decision based on that set.
That is just wrong -- all set backends support lookups (else they would
not be very useful).
The failure comes from an explicit rejection in nft_lookup.c.
Looking at the history, it seems like NFT_SET_EVAL used to mean
'set contains expressions' (aka. "is a meter"), for instance something like
nft add rule ip filter input meter example { ip saddr limit rate 10/second }
or
nft add rule ip filter input meter example { ip saddr counter }
The actual meaning of NFT_SET_EVAL however, is
'set can be updated from the packet path'.
'meters' and packet-path insertions into sets, such as
'add @set { ip saddr }' use exactly the same kernel code (nft_dynset.c)
and thus require a set backend that provides the ->update() function.
The only set that provides this also is the only one that has the
NFT_SET_EVAL feature flag.
Removing the wrong check makes the above example work.
While at it, also fix the flag check during set instantiation to
allow supported combinations only.
Fixes: 8aeff920dcc9b3f ("netfilter: nf_tables: add stateful object reference to set elements") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
If client mds session is evicted in CEPH_MDS_SESSION_OPENING state,
mds won't send session msg to client, and delayed_work skip
CEPH_MDS_SESSION_OPENING state session, the session hang forever.
Allow ceph_con_keepalive to reconnect a session in OPENING to avoid
session hang. Also, ensure that we skip sessions in RESTARTING and
REJECTED states since those states can't be resurrected by issuing
a keepalive.
When filling an inode with info from the MDS, i_blkbits is being
initialized using fl_stripe_unit, which contains the stripe unit in
bytes. Unfortunately, this doesn't make sense for directories as they
have fl_stripe_unit set to '0'. This means that i_blkbits will be set
to 0xff, causing an UBSAN undefined behaviour in i_blocksize():
UBSAN: Undefined behaviour in ./include/linux/fs.h:731:12
shift exponent 255 is too large for 32-bit type 'int'
Fix this by initializing i_blkbits to CEPH_BLOCK_SHIFT if fl_stripe_unit
is zero.
Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
If MCFG area is not reserved in E820, Xen by default will defer its usage
until Dom0 registers it explicitly after ACPI parser recognizes it as
a reserved resource in DSDT. Having it reserved in E820 is not
mandatory according to "PCI Firmware Specification, rev 3.2" (par. 4.1.2)
and firmware is free to keep a hole in E820 in that place. Xen doesn't know
what exactly is inside this hole since it lacks full ACPI view of the
platform therefore it's potentially harmful to access MCFG region
without additional checks as some machines are known to provide
inconsistent information on the size of the region.
Now xen_mcfg_late() runs after acpi_init() which is too late as some basic
PCI enumeration starts exactly there as well. Trying to register a device
prior to MCFG reservation causes multiple problems with PCIe extended
capability initializations in Xen (e.g. SR-IOV VF BAR sizing). There are
no convenient hooks for us to subscribe to so register MCFG areas earlier
upon the first invocation of xen_add_device(). It should be safe to do once
since all the boot time buses must have their MCFG areas in MCFG table
already and we don't support PCI bus hot-plug.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Currently on mmap cache policy, we always attach writeback_fid
whether mmap type is SHARED or PRIVATE. However, in the use case
of kata-container which combines 9p(Guest OS) with overlayfs(Host OS),
this behavior will trigger overlayfs' copy-up when excute command
inside container.
In encode_attrs(), there is an if statement on line 1145 to check
whether label is NULL:
if (label && (attrmask[2] & FATTR4_WORD2_SECURITY_LABEL))
When label is NULL, it is used on lines 1178-1181:
*p++ = cpu_to_be32(label->lfs);
*p++ = cpu_to_be32(label->pi);
*p++ = cpu_to_be32(label->len);
p = xdr_encode_opaque_fixed(p, label->label, label->len);
To fix these bugs, label is checked before being used.
These bugs are found by a static analysis tool STCheck written by us.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
integrity_kernel_read() returns the number of bytes read. If this is
a short read then this positive value is returned from
ima_calc_file_hash_atfm(). Currently this is only indirectly called from
ima_calc_file_hash() and this function only tests for the return value
being zero or nonzero and also doesn't forward the return value.
Nevertheless there's no point in returning a positive value as an error,
so translate a short read into -EINVAL.
In a few places we don't properly initialize on-stack chandefs,
resulting in EDMG data to be non-zero, which broke things.
Additionally, in a few places we rely on the driver to init the
data completely, but perhaps we shouldn't as non-EDMG drivers
may not initialize the EDMG data, also initialize it there.
Cc: stable@vger.kernel.org Fixes: 2a38075cd0be ("nl80211: Add support for EDMG channels") Reported-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Link: https://lore.kernel.org/r/1569239475-I2dcce394ecf873376c386a78f31c2ec8b538fa25@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
In case a user process using xenbus has open transactions and is killed
e.g. via ctrl-C the following cleanup of the allocated resources might
result in a deadlock due to trying to end a transaction in the xenbus
worker thread:
This patch reverts commit 75437bb304b20 (locking/pvqspinlock: Don't
wait if vCPU is preempted). A large performance regression was caused
by this commit. on over-subscription scenarios.
The test was run on a Xeon Skylake box, 2 sockets, 40 cores, 80 threads,
with three VMs of 80 vCPUs each. The score of ebizzy -M is reduced from
13000-14000 records/s to 1700-1800 records/s:
Exit from aggressive wait-early mechanism can result in premature yield
and extra scheduling latency.
Actually, only 6% of wait_early events are caused by vcpu_is_preempted()
being true. However, when one vCPU voluntarily releases its vCPU, all
the subsequently waiters in the queue will do the same and the cascading
effect leads to bad performance.
kvm optimizations:
[1] commit d73eb57b80b (KVM: Boost vCPUs that are delivering interrupts)
[2] commit 266e85a5ec9 (KVM: X86: Boost queue head vCPU to mitigate lock waiter preemption)
Tested-by: loobinliu@tencent.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Waiman Long <longman@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: loobinliu@tencent.com Cc: stable@vger.kernel.org Fixes: 75437bb304b20 (locking/pvqspinlock: Don't wait if vCPU is preempted) Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
We must not unconditionally set the DMA snoop bit; if the DMA API is
assuming that the device is not DMA coherent, and the device snoops the
CPU caches, the device can see stale cache lines brought in by
speculative prefetch.
This leads to the device seeing stale data, potentially resulting in
corrupted data transfers. Commonly, this results in a descriptor fetch
error such as:
but can lead to other errors, and potentially direct the SDHCI
controller to read/write data to other memory locations (e.g. if a valid
descriptor is visible to the device in a stale cache line.)
Fix this by ensuring that the DMA snoop bit corresponds with the
behaviour of the DMA API. Since the driver currently only supports DT,
use of_dma_is_coherent(). Note that device_get_dma_attr() can not be
used as that risks re-introducing this bug if/when the driver is
converted to ACPI.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
ADMA errors are potentially data corrupting events; although we print
the register state, we do not usefully print the ADMA descriptors.
Worse than that, we print them by referencing their virtual address
which is meaningless when the register state gives us the DMA address
of the failing descriptor.
Print the ADMA descriptors giving their DMA addresses rather than their
virtual addresses, and print them using SDHCI_DUMP() rather than DBG().
We also do not show the correct value of the interrupt status register;
the register dump shows the current value, after we have cleared the
pending interrupts we are going to service. What is more useful is to
print the interrupts that _were_ pending at the time the ADMA error was
encountered. Fix that too.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The OMAP36xx and AM/DM37x TRMs say that the maximum divider for DSS fclk
(in CM_CLKSEL_DSS) is 32. Experimentation shows that this is not
correct, and using divider of 32 breaks DSS with a flood or underflows
and sync losts. Dividers up to 31 seem to work fine.
There is another patch to the DT files to limit the divider correctly,
but as the DSS driver also needs to know the maximum divider to be able
to iteratively find good rates, we also need to do the fix in the DSS
driver.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Adam Ford <aford173@gmail.com> Cc: stable@vger.kernel.org Link: https://patchwork.freedesktop.org/patch/msgid/20191002122542.8449-1-tomi.valkeinen@ti.com Tested-by: Adam Ford <aford173@gmail.com> Reviewed-by: Jyri Sarha <jsarha@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Converting from ms to s requires dividing by 1000, not multiplying. So
this is currently taking the smaller of new_timeout and 1.28e8,
i.e. effectively new_timeout.
The driver knows what it set max_hw_heartbeat_ms to, so use that
value instead of doing a division at run-time.
FWIW, this can easily be tested by booting into a busybox shell and
doing "watchdog -t 5 -T 130 /dev/watchdog" - without this patch, the
watchdog fires after 130&127 == 2 seconds.
Fixes: b07e228eee69 "watchdog: imx2_wdt: Fix set_timeout for big timeout values" Cc: stable@vger.kernel.org # 5.2 plus anything the above got backported to Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20190812131356.23039-1-linux@rasmusvillemoes.dk Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The reason is that the code in collect_expired_timers() uses jiffies
unprotected:
if (next_event > jiffies)
base->clk = jiffies;
As the compiler is allowed to reload the value base->clk can advance
between the check and the store and in the worst case advance farther than
next event. That causes the timer expiry to be delayed until the wheel
pointer wraps around.
Convert the code to use READ_ONCE()
Fixes: 236968383cf5 ("timers: Optimize collect_expired_timers() for NOHZ") Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Liang ZhiCheng <liangzhicheng@baidu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1568894687-14499-1-git-send-email-lirongqing@baidu.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
all execve()s will fail due to argv copying into kmap()ed pages, and on
usercopy checking the calls ultimately of virt_to_page() will be looking
for "bad" kmap (highmem) pointers due to CONFIG_DEBUG_VIRTUAL=y:
kaddr = kmap(kmapped_page);
...
if (copy_from_user(kaddr+offset, str, bytes_to_copy)) ...
Now we can fetch the correct page to avoid the pfn check. In both cases,
hardened usercopy will need to walk the page-span checker (if enabled)
to do sanity checking.
Reported-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Fixes: f5509cc18daa ("mm: Hardened usercopy") Cc: Matthew Wilcox <willy@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/201909171056.7F2FFD17@keescook Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
IV transfer from ofifo to class2 (set up at [29][30]) is not guaranteed
to be scheduled before the data transfer from ofifo to external memory
(set up at [38]:
If ofifo -> external memory transfer happens first, DECO will hang
(issuing a Watchdog Timeout error, if WDOG is enabled) waiting for
data availability in ofifo for the ofifo -> c2 ififo transfer.
Make sure IV transfer happens first by waiting for all CAAM internal
transfers to end before starting payload transfer.
New descriptor with jump command inserted at [37]:
[Note: the issue is present in the descriptor from the very beginning
(cf. Fixes tag). However I've marked it v4.19+ since it's the oldest
maintained kernel that the patch applies clean against.]
skcipher_walk_done may be called with an error by internal or
external callers. For those internal callers we shouldn't unmap
pages but for external callers we must unmap any pages that are
in use.
This patch distinguishes between the two cases by checking whether
walk->nbytes is zero or not. For internal callers, we now set
walk->nbytes to zero prior to the call. For external callers,
walk->nbytes has always been non-zero (as zero is used to indicate
the termination of a walk).
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Fixes: 5cde0af2a982 ("[CRYPTO] cipher: Added block cipher type") Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
It seems that smp_processor_id() is only used for a best-effort
load-balancing, refer to qat_crypto_get_instance_node(). It's not feasible
to disable preemption for the duration of the crypto requests. Therefore,
just silence the warning. This commit is similar to e7a9b05ca4
("crypto: cavium - Fix smp_processor_id() warnings").
Silences the following splat:
BUG: using smp_processor_id() in preemptible [00000000] code: cryptomgr_test/2904
caller is qat_alg_ablkcipher_setkey+0x300/0x4a0 [intel_qat]
CPU: 1 PID: 2904 Comm: cryptomgr_test Tainted: P O 4.14.69 #1
...
Call Trace:
dump_stack+0x5f/0x86
check_preemption_disabled+0xd3/0xe0
qat_alg_ablkcipher_setkey+0x300/0x4a0 [intel_qat]
skcipher_setkey_ablkcipher+0x2b/0x40
__test_skcipher+0x1f3/0xb20
? cpumask_next_and+0x26/0x40
? find_busiest_group+0x10e/0x9d0
? preempt_count_add+0x49/0xa0
? try_module_get+0x61/0xf0
? crypto_mod_get+0x15/0x30
? __kmalloc+0x1df/0x1f0
? __crypto_alloc_tfm+0x116/0x180
? crypto_skcipher_init_tfm+0xa6/0x180
? crypto_create_tfm+0x4b/0xf0
test_skcipher+0x21/0xa0
alg_test_skcipher+0x3f/0xa0
alg_test.part.6+0x126/0x2a0
? finish_task_switch+0x21b/0x260
? __schedule+0x1e9/0x800
? __wake_up_common+0x8d/0x140
cryptomgr_test+0x40/0x50
kthread+0xff/0x130
? cryptomgr_notify+0x540/0x540
? kthread_create_on_node+0x70/0x70
ret_from_fork+0x24/0x50
Fixes: ed8ccaef52 ("crypto: qat - Add support for SRIOV") Cc: stable@vger.kernel.org Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The tools/lib/traceevent/Makefile had a test added to it to detect a failure
of the "nm" when making the dynamic list file (whatever that is). The
problem is that the test sorts the values "U W w" and some versions of sort
will place "w" ahead of "W" (even though it has a higher ASCII value, and
break the test.
Add 'tr "w" "W"' to merge the two and not worry about the ordering.
Reported-by: Tzvetomir Stoyanov <tstoyanov@vmware.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Michal rarek <mmarek@suse.com> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Wang Nan <wangnan0@huawei.com> Cc: stable@vger.kernel.org Fixes: 6467753d61399 ("tools lib traceevent: Robustify do_generate_dynamic_list_file") Link: http://lkml.kernel.org/r/20190805130150.25acfeb1@gandalf.local.home Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The kHz to Hz is incorrectly converted in a few places in the code,
this results in a wrong frequency being calculated because devfreq core
uses OPP frequencies that are given in Hz to clamp the rate, while
tegra-devfreq gives to the core value in kHz and then it also expects to
receive value in kHz from the core. In a result memory freq is always set
to a value which is close to ULONG_MAX because of the bug. Hence the EMC
frequency is always capped to the maximum and the driver doesn't do
anything useful. This patch was tested on Tegra30 and Tegra124 SoC's, EMC
frequency scaling works properly now.
On POWER9, when userspace reads the value of the DPDES register on a
vCPU, it is possible for 0 to be returned although there is a doorbell
interrupt pending for the vCPU. This can lead to a doorbell interrupt
being lost across migration. If the guest kernel uses doorbell
interrupts for IPIs, then it could malfunction because of the lost
interrupt.
This happens because a newly-generated doorbell interrupt is signalled
by setting vcpu->arch.doorbell_request to 1; the DPDES value in
vcpu->arch.vcore->dpdes is not updated, because it can only be updated
when holding the vcpu mutex, in order to avoid races.
To fix this, we OR in vcpu->arch.doorbell_request when reading the
DPDES value.
Cc: stable@vger.kernel.org # v4.13+ Fixes: 579006944e0d ("KVM: PPC: Book3S HV: Virtualize doorbell facility on POWER9") Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
ccw console is created early in start_kernel and used before css is
initialized or ccw console subchannel is registered. Until then console
subchannel does not have a parent. For that reason assume subchannels
with no parent are not pseudo subchannels. This fixes the following
kasan finding:
BUG: KASAN: global-out-of-bounds in sch_is_pseudo_sch+0x8e/0x98
Read of size 8 at addr 00000000000005e8 by task swapper/0/0
Fix the following kasan finding:
BUG: KASAN: global-out-of-bounds in ccwgroup_create_dev+0x850/0x1140
Read of size 1 at addr 0000000000000000 by task systemd-udevd.r/561
If the KVM_S390_MEM_OP ioctl is called with an access register >= 16,
then there is certainly a bug in the calling userspace application.
We check for wrong access registers, but only if the vCPU was already
in the access register mode before (i.e. the SIE block has recorded
it). The check is also buried somewhere deep in the calling chain (in
the function ar_translation()), so this is somewhat hard to find.
It's better to always report an error to the userspace in case this
field is set wrong, and it's safer in the KVM code if we block wrong
values here early instead of relying on a check somewhere deep down
the calling chain, so let's add another check to kvm_s390_guest_mem_op()
directly.
We also should check that the "size" is non-zero here (thanks to Janosch
Frank for the hint!). If we do not check the size, we could call vmalloc()
with this 0 value, and this will cause a kernel warning.
Signed-off-by: Thomas Huth <thuth@redhat.com> Link: https://lkml.kernel.org/r/20190829122517.31042-1-thuth@redhat.com Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
With THREAD_INFO_IN_TASK (which is selected on s390) task's stack usage
is refcounted and should always be protected by get/put when touching
other task's stack to avoid race conditions with task's destruction code.
This commit has caused failure to launch 64-bit linux VMs when kvm-intel
ept module parameter is off. It is off by default on old Intel CPUs.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Acked-by: Tyler Hicks <tyhicks@canonical.com> Acked-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
BugLink: https://launchpad.net/bugs/1852141
When a jump_whitelist bitmap is reused, it needs to be cleared.
Currently this is done with memset() and the size calculation assumes
bitmaps are made of 32-bit words, not longs. So on 64-bit
architectures, only the first half of the bitmap is cleared.
If some whitelist bits are carried over between successive batches
submitted on the same context, this will presumably allow embedding
the rogue instructions that we're trying to reject.
Use bitmap_zero() instead, which gets the calculation right.
Fixes: f8c08d8faee5 ("drm/i915/cmdparser: Add support for backward jumps") Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
CVE-2019-0155
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jack Wang [Mon, 7 Oct 2019 12:36:53 +0000 (14:36 +0200)]
KVM: nVMX: handle page fault in vmread fix
BugLink: https://launchpad.net/bugs/1851205
During backport f7eea636c3d5 ("KVM: nVMX: handle page fault in vmread"),
there was a mistake the exception reference should be passed to function
kvm_write_guest_virt_system, instead of NULL, other wise, we will get
NULL pointer deref, eg
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 5ff375e9dcb5a9ec75f460aaa61fd605a731dda9 linux-stable) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
[tyhicks Backport to 5.0
- Minor context adjustment due to missing kvm_set_mmio_spte_mask()] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Tyler Hicks [Fri, 1 Nov 2019 15:21:39 +0000 (15:21 +0000)]
UBUNTU: SAUCE: cpu/speculation: Uninline and export CPU mitigations helpers
A kernel module may need to check the value of the "mitigations=" kernel
command line parameter as part of its setup when the module needs
to perform software mitigations for a CPU flaw. Uninline and export the
helper functions surrounding the cpu_mitigations enum to allow for their
usage from a module. Lastly, privatize the enum and cpu_mitigations
variable since the value of cpu_mitigations can be checked with the
exported helper functions.
Junaid Shahid [Thu, 31 Oct 2019 23:33:47 +0000 (00:33 +0100)]
UBUNTU: SAUCE: kvm: x86: mmu: Recovery of shattered NX large pages
The page table pages corresponding to broken down large pages are
zapped in FIFO order, so that the large page can potentially
be recovered, if it is no longer being used for execution. This removes
the performance penalty for walking deeper EPT page tables.
By default, one large page will last about one hour once the guest
reaches a steady state.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
[tyhicks: Backport to 4.15
- Minor context adjustments due to different members of struct
kvm_mmu_page and kvm_arch] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Junaid Shahid [Thu, 31 Oct 2019 23:33:46 +0000 (00:33 +0100)]
UBUNTU: SAUCE: kvm: Add helper function for creating VM worker threads
This adds a function to create a kernel thread associated with a given
VM. In particular, it ensures that the worker thread inherits the
priority and cgroups of the calling thread.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
[tyhicks: Backport to 4.15
- Fix up conflicts in #includes of kvm_main.c
- Minor context adjustments in kvm_host.h] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Thu, 31 Oct 2019 23:33:45 +0000 (00:33 +0100)]
UBUNTU: SAUCE: kvm: mmu: ITLB_MULTIHIT mitigation
With some Intel processors, putting the same virtual address in the TLB
as both a 4 KiB and 2 MiB page can confuse the instruction fetch unit
and cause the processor to issue a machine check. Unfortunately if EPT
page tables use huge pages, it possible for a malicious guest to cause
this situation.
This patch adds a knob to mark huge pages as non-executable. When the
nx_huge_pages parameter is enabled (and we are using EPT), all huge pages
are marked as NX. If the guest attempts to execute in one of those pages,
the page is broken down into 4K pages, which are then marked executable.
This is not an issue for shadow paging (except nested EPT), because then
the host is in control of TLB flushes and the problematic situation cannot
happen. With nested EPT, again the nested guest can cause problems so we
treat shadow and direct EPT the same.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
[tyhicks: Backport to 4.15
- Context adjustments due to missing mmio_cached and unsync members of
struct kvm_mmu_page and missing kvm_set_mmio_spte_mask()
- Call kvm_mmu_invalidate_zap_all_pages() instead of
kvm_mmu_zap_all_fast() since the latter does not exist] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Some processors may incur a machine check error possibly
resulting in an unrecoverable cpu hang when an instruction fetch
encounters a TLB multi-hit in the instruction TLB. This can occur
when the page size is changed along with either the physical
address or cache type [1].
This issue affects both bare-metal x86 page tables and EPT.
This can be mitigated by either eliminating the use of large
pages or by using careful TLB invalidations when changing the
page size in the page tables.
Just like Spectre, Meltdown, L1TF and MDS, a new bit has been
allocated in MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will
be set on CPUs which are mitigated against this issue.
[1] For example please refer to erratum SKL002 in "6th Generation
Intel Processor Family Specification Update"
https://www.intel.com/content/www/us/en/products/docs/processors/core/desktop-6th-gen-core-family-spec-update.html
https://www.google.com/search?q=site:intel.com+SKL002
There are a lot of other affected processors outside of Skylake and
that the erratum(referred above) does not fully disclose the issue
and the impact, both on Skylake and across all the affected CPUs.
[tyhicks: Backport to 4.15
- ATOM_SILVERMONT_D is ATOM_SILVERMONT_X
- ATOM_AIRMONT_NP does not yet exist
- ATOM_GOLDMONT_D is ATOM_GOLDMONT_X
- Hygon isn't supported to VULNWL_HYGON() does not exist] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Sun, 27 Oct 2019 15:23:23 +0000 (16:23 +0100)]
UBUNTU: SAUCE: KVM: vmx, svm: always run with EFER.NXE=1 when shadow paging is active
VMX already does so if the host has SMEP, in order to support the combination of
CR0.WP=1 and CR4.SMEP=1. However, it is perfectly safe to always do so, and in
fact VMX already ends up running with EFER.NXE=1 on old processors that lack the
"load EFER" controls, because it may help avoiding a slow MSR write. Removing
all the conditionals simplifies the code.
SVM does not have similar code, but it should since recent AMD processors do
support SMEP. So this patch also makes the code for the two vendors more similar
while fixing NPT=0, CR0.WP=1 and CR4.SMEP=1 on AMD processors.
[tyhicks: Backport to 4.15
- vmx.c is up one directory level] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Mon, 30 Sep 2019 16:48:44 +0000 (18:48 +0200)]
kvm: x86, powerpc: do not allow clearing largepages debugfs entry
The largepages debugfs entry is incremented/decremented as shadow
pages are created or destroyed. Clearing it will result in an
underflow, which is harmless to KVM but ugly (and could be
misinterpreted by tools that use debugfs information), so make
this particular statistic read-only.
Cc: kvm-ppc@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(backported from commit 833b45de69a6016c4b0cebe6765d526a31a81580)
[tyhicks: Backport to 4.15
- largepages_* are not present in the debugfs_entries list in book3s.c
- VM_STAT() does not exist in book3s.c
- Calls to debugfs_create_file() are error checked] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Sun, 30 Jun 2019 12:36:21 +0000 (08:36 -0400)]
KVM: x86: change kvm_mmu_page_get_gfn BUG_ON to WARN_ON
Note that in such a case it is quite likely that KVM will BUG_ON
in __pte_list_remove when the VM is closed. However, there is no
immediate risk of memory corruption in the host so a WARN_ON is
enough and it lets you gather traces for debugging.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(cherry picked from commit e9f2a760b158551bfbef6db31d2cae45ab8072e5) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Sun, 23 Jun 2019 17:15:49 +0000 (19:15 +0200)]
KVM: x86: remove now unneeded hugepage gfn adjustment
After the previous patch, the low bits of the gfn are masked in
both FNAME(fetch) and __direct_map, so we do not need to clear them
in transparent_hugepage_adjust.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(cherry picked from commit d679b32611c0102ce33b9e1a4e4b94854ed1812a) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Mon, 24 Jun 2019 11:06:21 +0000 (13:06 +0200)]
KVM: x86: make FNAME(fetch) and __direct_map more similar
These two functions are basically doing the same thing through
kvm_mmu_get_page, link_shadow_page and mmu_set_spte; yet, for historical
reasons, their code looks very different. This patch tries to take the
best of each and make them very similar, so that it is easy to understand
changes that apply to both of them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(backported from commit 3fcf2d1bdeb6a513523cb2c77012a6b047aa859c)
[tyhicks: Backport to 4.15
- Minor context change due to mmu not being a pointer in the
kvm_vcpu_arch struct] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Junaid Shahid [Fri, 4 Jan 2019 00:22:21 +0000 (16:22 -0800)]
kvm: x86: Do not release the page inside mmu_set_spte()
Release the page at the call-site where it was originally acquired.
This makes the exit code cleaner for most call sites, since they
do not need to duplicate code between success and the failure
label.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(cherry picked from commit 43fdcda96e2550c6d1c46fb8a78801aa2f7276ed) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Junaid Shahid [Fri, 4 Jan 2019 01:14:28 +0000 (17:14 -0800)]
kvm: Convert kvm_lock to a mutex
It doesn't seem as if there is any particular need for kvm_lock to be a
spinlock, so convert the lock to a mutex so that sleepable functions (in
particular cond_resched()) can be called while holding it.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(backported from commit 0d9ce162cf46c99628cc5da9510b959c7976735b)
[tyhicks: Backport to 4.15
- kvm_hyperv_tsc_notifier() does not exist] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Tyler Hicks [Wed, 30 Oct 2019 03:28:46 +0000 (03:28 +0000)]
UBUNTU: [Config] Disable TSX by default when possible
Turn on CONFIG_X86_INTEL_TSX_MODE_OFF to disable Intel's Transactional
Synchronization Extensions (TSX) feature by default. TSX can only be
disable on certain, newer processors that support the IA32_TSX_CTRL MSR
via a microcode update. Intel says that future processors will also
support the MSR. On processors that support the MSR, TSX will be
disabled unless the system administrator overrides the configuration
with the "tsx" kernel command line option.
CVE-2019-11135
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Tyler Hicks [Tue, 29 Oct 2019 21:58:08 +0000 (21:58 +0000)]
UBUNTU: SAUCE: x86/cpu: Include cpu header from bugs.c
The linux-4.14.y backport of commit 286836a70433 ("x86/cpu: Add a helper
function x86_read_arch_cap_msr()") added a dependency on cpu.h from
bugs.c so include the header file from bugs.c
The linux-4.14.y backport of upstream commit 95c5824f75f3 ("x86/cpu: Add
a "tsx=" cmdline option with TSX disabled by default") incorrectly
dropped the call to tsx_init(). Add the function call back to
identify_boot_cpu()
There is a general consensus that TSX usage is not largely spread while
the history shows there is a non trivial space for side channel attacks
possible. Therefore the tsx is disabled by default even on platforms
that might have a safe implementation of TSX according to the current
knowledge. This is a fair trade off to make.
There are, however, workloads that really do benefit from using TSX and
updating to a newer kernel with TSX disabled might introduce a
noticeable regressions. This would be especially a problem for Linux
distributions which will provide TAA mitigations.
Introduce config options X86_INTEL_TSX_MODE_OFF, X86_INTEL_TSX_MODE_ON
and X86_INTEL_TSX_MODE_AUTO to control the TSX feature. The config
setting can be overridden by the tsx cmdline options.
Add the documenation for TSX Async Abort. Include the description of
the issue, how to check the mitigation state, control the mitigation,
guidance for system administrators.
[ bp: Add proper SPDX tags, touch ups by Josh and me. ]
Co-developed-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
CVE-2019-11135
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Platforms which are not affected by X86_BUG_TAA may want the TSX feature
enabled. Add "auto" option to the TSX cmdline parameter. When tsx=auto
disable TSX when X86_BUG_TAA is present, otherwise enable TSX.
More details on X86_BUG_TAA can be found here:
https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html
[ bp: Extend the arg buffer to accommodate "auto\0". ]
Export the IA32_ARCH_CAPABILITIES MSR bit MDS_NO=0 to guests on TSX
Async Abort(TAA) affected hosts that have TSX enabled and updated
microcode. This is required so that the guests don't complain,
"Vulnerable: Clear CPU buffers attempted, no microcode"
when the host has the updated microcode to clear CPU buffers.
Microcode update also adds support for MSR_IA32_TSX_CTRL which is
enumerated by the ARCH_CAP_TSX_CTRL bit in IA32_ARCH_CAPABILITIES MSR.
Guests can't do this check themselves when the ARCH_CAP_TSX_CTRL bit is
not exported to the guests.
In this case export MDS_NO=0 to the guests. When guests have
CPUID.MD_CLEAR=1, they deploy MDS mitigation which also mitigates TAA.
Add the sysfs reporting file for TSX Async Abort. It exposes the
vulnerability and the mitigation state similar to the existing files for
the other hardware vulnerabilities.
Sysfs file path is:
/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
TSX Async Abort (TAA) is a side channel vulnerability to the internal
buffers in some Intel processors similar to Microachitectural Data
Sampling (MDS). In this case, certain loads may speculatively pass
invalid data to dependent operations when an asynchronous abort
condition is pending in a TSX transaction.
This includes loads with no fault or assist condition. Such loads may
speculatively expose stale data from the uarch data structures as in
MDS. Scope of exposure is within the same-thread and cross-thread. This
issue affects all current processors that support TSX, but do not have
ARCH_CAP_TAA_NO (bit 8) set in MSR_IA32_ARCH_CAPABILITIES.
On CPUs which have their IA32_ARCH_CAPABILITIES MSR bit MDS_NO=0,
CPUID.MD_CLEAR=1 and the MDS mitigation is clearing the CPU buffers
using VERW or L1D_FLUSH, there is no additional mitigation needed for
TAA. On affected CPUs with MDS_NO=1 this issue can be mitigated by
disabling the Transactional Synchronization Extensions (TSX) feature.
A new MSR IA32_TSX_CTRL in future and current processors after a
microcode update can be used to control the TSX feature. There are two
bits in that MSR:
* TSX_CTRL_RTM_DISABLE disables the TSX sub-feature Restricted
Transactional Memory (RTM).
* TSX_CTRL_CPUID_CLEAR clears the RTM enumeration in CPUID. The other
TSX sub-feature, Hardware Lock Elision (HLE), is unconditionally
disabled with updated microcode but still enumerated as present by
CPUID(EAX=7).EBX{bit4}.
The second mitigation approach is similar to MDS which is clearing the
affected CPU buffers on return to user space and when entering a guest.
Relevant microcode update is required for the mitigation to work. More
details on this approach can be found here:
The TSX feature can be controlled by the "tsx" command line parameter.
If it is force-enabled then "Clear CPU buffers" (MDS mitigation) is
deployed. The effective mitigation state can be read from sysfs.
Add a kernel cmdline parameter "tsx" to control the Transactional
Synchronization Extensions (TSX) feature. On CPUs that support TSX
control, use "tsx=on|off" to enable or disable TSX. Not specifying this
option is equivalent to "tsx=off". This is because on certain processors
TSX may be used as a part of a speculative side channel attack.
Carve out the TSX controlling functionality into a separate compilation
unit because TSX is a CPU feature while the TSX async abort control
machinery will go to cpu/bugs.c.
[ bp: - Massage, shorten and clear the arg buffer.
- Clarifications of the tsx= possible options - Josh.
- Expand on TSX_CTRL availability - Pawan. ]
Transactional Synchronization Extensions (TSX) may be used on certain
processors as part of a speculative side channel attack. A microcode
update for existing processors that are vulnerable to this attack will
add a new MSR - IA32_TSX_CTRL to allow the system administrator the
option to disable TSX as one of the possible mitigations.
The CPUs which get this new MSR after a microcode upgrade are the ones
which do not set MSR_IA32_ARCH_CAPABILITIES.MDS_NO (bit 5) because those
CPUs have CPUID.MD_CLEAR, i.e., the VERW implementation which clears all
CPU buffers takes care of the TAA case as well.
[ Note that future processors that are not vulnerable will also
support the IA32_TSX_CTRL MSR. ]
Add defines for the new IA32_TSX_CTRL MSR and its bits.
TSX has two sub-features:
1. Restricted Transactional Memory (RTM) is an explicitly-used feature
where new instructions begin and end TSX transactions.
2. Hardware Lock Elision (HLE) is implicitly used when certain kinds of
"old" style locks are used by software.
Bit 7 of the IA32_ARCH_CAPABILITIES indicates the presence of the
IA32_TSX_CTRL MSR.
There are two control bits in IA32_TSX_CTRL MSR:
Bit 0: When set, it disables the Restricted Transactional Memory (RTM)
sub-feature of TSX (will force all transactions to abort on the
XBEGIN instruction).
Bit 1: When set, it disables the enumeration of the RTM and HLE feature
(i.e. it will make CPUID(EAX=7).EBX{bit4} and
CPUID(EAX=7).EBX{bit11} read as 0).
The other TSX sub-feature, Hardware Lock Elision (HLE), is
unconditionally disabled by the new microcode but still enumerated
as present by CPUID(EAX=7).EBX{bit4}, unless disabled by
IA32_TSX_CTRL_MSR[1] - TSX_CTRL_CPUID_CLEAR.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
CVE-2019-11135
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Similar to AMD bits, set the Intel bits from the vendor-independent
feature and bug flags, because KVM_GET_SUPPORTED_CPUID does not care
about the vendor and they should be set on AMD processors as well.
Suggested-by: Jim Mattson <jmattson@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
CVE-2019-11135
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Imre Deak [Mon, 9 Jul 2018 15:24:27 +0000 (18:24 +0300)]
UBUNTU: SAUCE: drm/i915/gen8+: Add RC6 CTX corruption WA
In some circumstances the RC6 context can get corrupted. We can detect
this and take the required action, that is disable RC6 and runtime PM.
The HW recovers from the corrupted state after a system suspend/resume
cycle, so detect the recovery and re-enable RC6 and runtime PM.
v2: rebase (Mika)
v3:
- Move intel_suspend_gt_powersave() to the end of the GEM suspend
sequence.
- Add commit message.
v4:
- Rebased on intel_uncore_forcewake_put(i915->uncore, ...) API
change.
v5: rebased on gem/gt split (Mika)
Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
CVE-2019-0154
[tyhicks: Backport to 4.15
- Don't use intel_wakeref_t since it doesn't exist. I followed Intel's
lead by copying what they did in their 4.19-stable backport.
- Take dev_priv->pcu_lock in intel_disable_rc6(). I followed Intel's
lead by copying what they did in their 4.19-stable backport.
- Use INTEL_GEN() instead of IS_GEN()
- Quite a few context adjustments throughout the entire patch] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Uma Shankar [Tue, 7 Aug 2018 15:45:35 +0000 (21:15 +0530)]
UBUNTU: SAUCE: drm/i915: Lower RM timeout to avoid DSI hard hangs
In BXT/APL, device 2 MMIO reads from MIPI controller requires its PLL
to be turned ON. When MIPI PLL is turned off (MIPI Display is not
active or connected), and someone (host or GT engine) tries to read
MIPI registers, it causes hard hang. This is a hardware restriction
or limitation.
Driver by itself doesn't read MIPI registers when MIPI display is off.
But any userspace application can submit unprivileged batch buffer for
execution. In that batch buffer there can be mmio reads. And these
reads are allowed even for unprivileged applications. If these
register reads are for MIPI DSI controller and MIPI display is not
active during that time, then the MMIO read operation causes system
hard hang and only way to recover is hard reboot. A genuine
process/application won't submit batch buffer like this and doesn't
cause any issue. But on a compromised system, a malign userspace
process/app can generate such batch buffer and can trigger system
hard hang (denial of service attack).
The fix is to lower the internal MMIO timeout value to an optimum
value of 950us as recommended by hardware team. If the timeout is
beyond 1ms (which will hit for any value we choose if MMIO READ on a
DSI specific register is performed without PLL ON), it causes the
system hang. But if the timeout value is lower than it will be below
the threshold (even if timeout happens) and system will not get into
a hung state. This will avoid a system hang without losing any
programming or GT interrupts, taking the worst case of lowest CDCLK
frequency and early DC5 abort into account.
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
CVE-2019-0154
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jon Bloomfield [Thu, 20 Sep 2018 16:45:10 +0000 (09:45 -0700)]
UBUNTU: SAUCE: drm/i915/cmdparser: Ignore Length operands during command matching
Some of the gen instruction macros (e.g. MI_DISPLAY_FLIP) have the
length directly encoded in them. Since these are used directly in
the tables, the Length becomes part of the comparison used for
matching during parsing. Thus, if the cmd being parsed has a
different length to that in the table, it is not matched and the
cmd is accepted via the default variable length path.
Fix by masking out everything except the Opcode in the cmd tables
Signed-off-by: Jon Bloomfield <jon.bloomfield@intel.com>
CVE-2019-0155
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jon Bloomfield [Thu, 20 Sep 2018 16:58:36 +0000 (09:58 -0700)]
UBUNTU: SAUCE: drm/i915/cmdparser: Add support for backward jumps
To keep things manageable, the pre-gen9 cmdparser does not
attempt to track any form of nested BB_START's. This did not
prevent usermode from using nested starts, or even chained
batches because the cmdparser is not strictly enforced pre gen9.
Instead, the existence of a nested BB_START would cause the batch
to be emitted in insecure mode, and any privileged capabilities
would not be available.
For Gen9, the cmdparser becomes mandatory (for BCS at least), and
so not providing any form of nested BB_START support becomes
overly restrictive. Any such batch will simply not run.
We make heavy use of backward jumps in igt, and it is much easier
to add support for this restricted subset of nested jumps, than to
rewrite the whole of our test suite to avoid them.
Add the required logic to support limited backward jumps, to
instructions that have already been validated by the parser.
Note that it's not sufficient to simply approve any BB_START
that jumps backwards in the buffer because this would allow an
attacker to embed a rogue instruction sequence within the
operand words of a harmless instruction (say LRI) and jump to
that.
We introduce a bit array to track every instr offset successfully
validated, and test the target of BB_START against this. If the
target offset hits, it is re-written to the same offset in the
shadow buffer and the BB_START cmd is allowed.
Note: This patch deliberately ignores checkpatch issues in the
cmdtables, in order to match the style of the surrounding code.
We'll correct the entire file in one go in a later patch.
v2: set dispatch secure late (Mika)
v3: rebase (Mika)
v4: Clear whitelist on each parse
Minor review updates (Chris)
v5: Correct backward jump batching
v6: fix compilation error due to struct eb shuffle (Mika)
Signed-off-by: Jon Bloomfield <jon.bloomfield@intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
CVE-2019-0155
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jon Bloomfield [Thu, 27 Sep 2018 17:23:17 +0000 (10:23 -0700)]
UBUNTU: SAUCE: drm/i915/cmdparser: Use explicit goto for error paths
In the next patch we will be adding a second valid
termination condition which will require a small
amount of refactoring to share logic with the BB_END
case.
Refactor all error conditions to jump to a dedicated
exit path, with 'break' reserved only for a successful
parse.
Signed-off-by: Jon Bloomfield <jon.bloomfield@intel.com>
CVE-2019-0155
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jon Bloomfield [Mon, 23 Apr 2018 18:12:15 +0000 (11:12 -0700)]
UBUNTU: SAUCE: drm/i915: Add gen9 BCS cmdparsing
For gen9 we enable cmdparsing on the BCS ring, specifically
to catch inadvertent accesses to sensitive registers
Unlike gen7/hsw, we use the parser only to block certain
registers. We can rely on h/w to block restricted commands,
so the command tables only provide enough info to allow the
parser to delineate each command, and identify commands that
access registers.
Note: This patch deliberately ignores checkpatch issues in
favour of matching the style of the surrounding code. We'll
correct the entire file in one go in a later patch.
v3: rebase (Mika)
v4: Add RING_TIMESTAMP registers to whitelist (Jon)
Jon Bloomfield [Wed, 1 Aug 2018 16:45:50 +0000 (09:45 -0700)]
UBUNTU: SAUCE: drm/i915: Allow parsing of unsized batches
In "drm/i915: Add support for mandatory cmdparsing" we introduced the
concept of mandatory parsing. This allows the cmdparser to be invoked
even when user passes batch_len=0 to the execbuf ioctl's.
However, the cmdparser needs to know the extents of the buffer being
scanned. Refactor the code to ensure the cmdparser uses the actual
object size, instead of the incoming length, if user passes 0.
Jon Bloomfield [Tue, 22 May 2018 20:59:06 +0000 (13:59 -0700)]
UBUNTU: SAUCE: drm/i915: Support ro ppgtt mapped cmdparser shadow buffers
For Gen7, the original cmdparser motive was to permit limited
use of register read/write instructions in unprivileged BB's.
This worked by copying the user supplied bb to a kmd owned
bb, and running it in secure mode, from the ggtt, only if
the scanner finds no unsafe commands or registers.
For Gen8+ we can't use this same technique because running bb's
from the ggtt also disables access to ppgtt space. But we also
do not actually require 'secure' execution since we are only
trying to reduce the available command/register set. Instead we
will copy the user buffer to a kmd owned read-only bb in ppgtt,
and run in the usual non-secure mode.
Note that ro pages are only supported by ppgtt (not ggtt), but
luckily that's exactly what we need.
Add the required paths to map the shadow buffer to ppgtt ro for Gen8+
Jon Bloomfield [Wed, 1 Aug 2018 16:33:59 +0000 (09:33 -0700)]
UBUNTU: SAUCE: drm/i915: Add support for mandatory cmdparsing
The existing cmdparser for gen7 can be bypassed by specifying
batch_len=0 in the execbuf call. This is safe because bypassing
simply reduces the cmd-set available.
In a later patch we will introduce cmdparsing for gen9, as a
security measure, which must be strictly enforced since without
it we are vulnerable to DoS attacks.
Introduce the concept of 'required' cmd parsing that cannot be
bypassed by submitting zero-length bb's.
Jon Bloomfield [Fri, 8 Jun 2018 15:53:46 +0000 (08:53 -0700)]
UBUNTU: SAUCE: drm/i915: Disable Secure Batches for gen6+
Retroactively stop reporting support for secure batches
through the api for gen6+ so that older binaries trigger
the fallback path instead.
Older binaries use secure batches pre gen6 to access resources
that are not available to normal usermode processes. However,
all known userspace explicitly checks for HAS_SECURE_BATCHES
before relying on the secure batch feature.
Since there are no known binaries relying on this for newer gens
we can kill secure batches from gen6, via I915_PARAM_HAS_SECURE_BATCHES.
Chris Wilson [Tue, 7 Nov 2017 15:40:55 +0000 (15:40 +0000)]
drm/i915: Silence smatch for cmdparser
drivers/gpu/drm/i915/i915_cmd_parser.c:808:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:811:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:814:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:808:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:811:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:814:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:808:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:811:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:814:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:808:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:811:23: error: not an lvalue
drivers/gpu/drm/i915/i915_cmd_parser.c:814:23: error: not an lvalue
If we move the shift into each case not only do we kill the warning from
smatch, but we shrink the code slightly:
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Matthew Auld <matthew.william.auld@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171107154055.19460-1-chris@chris-wilson.co.uk Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com> Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
CVE-2019-0155
(cherry picked from commit 0ffba1fc98e8ec35caae8d50b657296ebb9a9a51) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Michal Srb [Mon, 5 Feb 2018 16:04:38 +0000 (16:04 +0000)]
drm/i915/cmdparser: Do not check past the cmd length.
The command MEDIA_VFE_STATE checks bits at offset +2 dwords. However, it is
possible to have MEDIA_VFE_STATE command with length = 0 + LENGTH_BIAS = 2.
In that case check_cmd will read bits from the following command, or even past
the end of the buffer.
If the offset ends up outside of the command length, reject the command.
Michal Srb [Mon, 5 Feb 2018 16:04:37 +0000 (16:04 +0000)]
drm/i915/cmdparser: Check reg_table_count before derefencing.
The find_reg function was assuming that there is always at least one table in
reg_tables. It is not always true.
In case of VCS or VECS, the reg_tables is NULL and reg_table_count is 0,
implying that no register-accessing commands are allowed. However, the command
tables include commands such as MI_STORE_REGISTER_MEM. When trying to check
such command, the find_reg would dereference NULL pointer.
Now it will just return NULL meaning that the register was not found and the
command will be rejected.
Chris Wilson [Thu, 12 Jul 2018 18:53:13 +0000 (19:53 +0100)]
drm/i915: Prevent writing into a read-only object via a GGTT mmap
If the user has created a read-only object, they should not be allowed
to circumvent the write protection by using a GGTT mmapping. Deny it.
Also most machines do not support read-only GGTT PTEs, so again we have
to reject attempted writes. Fortunately, this is known a priori, so we
can at least reject in the call to create the mmap (with a sanity check
in the fault handler).
v2: Check the vma->vm_flags during mmap() to allow readonly access.
v3: Remove VM_MAYWRITE to curtail mprotect()
Testcase: igt/gem_userptr_blits/readonly_mmap* Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Jon Bloomfield <jon.bloomfield@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Matthew Auld <matthew.william.auld@gmail.com> Cc: David Herrmann <dh.herrmann@gmail.com> Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com> #v1 Reviewed-by: Jon Bloomfield <jon.bloomfield@intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180712185315.3288-4-chris@chris-wilson.co.uk
CVE-2019-0155
(backported from commit 3e977ac6179b39faa3c0eda5fce4f00663ae298d)
[tyhicks: Drop selftest changes] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Chris Wilson [Thu, 12 Jul 2018 18:53:12 +0000 (19:53 +0100)]
drm/i915/gtt: Disable read-only support under GVT
GVT is not propagating the PTE bits, and is always setting the
read-write bit, thus breaking read-only support.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Jon Bloomfield <jon.bloomfield@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Matthew Auld <matthew.william.auld@gmail.com> Reviewed-by: Jon Bloomfield <jon.bloomfield@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180712185315.3288-3-chris@chris-wilson.co.uk
CVE-2019-0155
(backported from commit c9e666880de5a1fed04dc412b046916d542b72dd)
[tyhicks: Backport to 4.15
- ggtt.vm is ggtt.base
- Pass dev_priv as the argument to intel_vgpu_active()] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jon Bloomfield [Thu, 12 Jul 2018 18:53:11 +0000 (19:53 +0100)]
drm/i915/gtt: Read-only pages for insert_entries on bdw+
Hook up the flags to allow read-only ppGTT mappings for gen8+
v2: Include a selftest to check that writes to a readonly PTE are
dropped
v3: Don't duplicate cpu_check() as we can just reuse it, and even worse
don't wholesale copy the theory-of-operation comment from igt_ctx_exec
without changing it to explain the intention behind the new test!
v4: Joonas really likes magic mystery values
Signed-off-by: Jon Bloomfield <jon.bloomfield@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Matthew Auld <matthew.william.auld@gmail.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180712185315.3288-2-chris@chris-wilson.co.uk
CVE-2019-0155
(backported from commit 250f8c8140ac0a5e5acb91891d6813f12778b224)
[tyhicks: Backport to 4.15
- ggtt.vm is ggtt.base
- Drop selftest changes] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jon Bloomfield [Thu, 12 Jul 2018 18:53:10 +0000 (19:53 +0100)]
drm/i915/gtt: Add read only pages to gen8_pte_encode
We can set a bit inside the ppGTT PTE to indicate a page is read-only;
writes from the GPU will be discarded. We can use this to protect pages
and in particular support read-only userptr mappings (necessary for
importing PROT_READ vma).
Signed-off-by: Jon Bloomfield <jon.bloomfield@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Matthew Auld <matthew.william.auld@gmail.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180712185315.3288-1-chris@chris-wilson.co.uk
CVE-2019-0155
(backported from commit 25dda4dabeeb12af5209b0183c788ef2a88dabbe)
[tyhicks: Adjust stack variable context in gen8_dump_ppgtt()] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>