commit 445c1470b6 upstream.
The x86 boot documentation describes the setup_indirect structures and
how they are used. Only one of the two functions in ioremap.c that needed
to be modified to be aware of the introduction of setup_indirect
functionality was updated. Adds comparable support to the other function
where it was missing.
Fixes: b3c72fc9a7 ("x86/boot: Introduce setup_indirect")
Signed-off-by: Ross Philipson <ross.philipson@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1645668456-22036-3-git-send-email-ross.philipson@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7228918b34 upstream.
As documented, the setup_indirect structure is nested inside
the setup_data structures in the setup_data list. The code currently
accesses the fields inside the setup_indirect structure but only
the sizeof(struct setup_data) is being memremapped. No crash
occurred but this is just due to how the area is remapped under the
covers.
Properly memremap both the setup_data and setup_indirect structures
in these cases before accessing them.
Fixes: b3c72fc9a7 ("x86/boot: Introduce setup_indirect")
Signed-off-by: Ross Philipson <ross.philipson@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1645668456-22036-2-git-send-email-ross.philipson@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4edc076041 upstream.
watch_queue_clear() has a comment stating that setting ->defunct to true
preventing new additions as well as preventing notifications. Whilst
the latter is true, the first bit is superfluous since at the time this
function is called, the pipe cannot be accessed to add new event
sources.
Remove the "new additions" bit from the comment.
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2ed147f015 upstream.
There's nothing to synchronise post_one_notification() versus
pipe_read(). Whilst posting is done under pipe->rd_wait.lock, the
reader only takes pipe->mutex which cannot bar notification posting as
that may need to be made from contexts that cannot sleep.
Fix this by setting pipe->head with a barrier in post_one_notification()
and reading pipe->head with a barrier in pipe_read().
If that's not sufficient, the rd_wait.lock will need to be taken,
possibly in a ->confirm() op so that it only applies to notifications.
The lock would, however, have to be dropped before copy_page_to_iter()
is invoked.
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3b4c037192 upstream.
Currently, watch_queue_set_size() sets the number of notes available in
wqueue->nr_notes according to the number of notes allocated, but sets
the size of the bitmap to the unrounded number of notes originally asked
for.
Fix this by setting the bitmap size to the number of notes we're
actually going to make available (ie. the number allocated).
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 96a4d8912b upstream.
The pipe ring size must always be a power of 2 as the head and tail
pointers are masked off by AND'ing with the size of the ring - 1.
watch_queue_set_size(), however, lets you specify any number of notes
between 1 and 511. This number is passed through to pipe_resize_ring()
without checking/forcing its alignment.
Fix this by rounding the number of slots required up to the nearest
power of two. The request is meant to guarantee that at least that many
notifications can be generated before the queue is full, so rounding
down isn't an option, but, alternatively, it may be better to give an
error if we aren't allowed to allocate that much ring space.
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c1853fbadc upstream.
When a pipe ring descriptor points to a notification message, the
refcount on the backing page is incremented by the generic get function,
but the release function, which marks the bitmap, doesn't drop the page
ref.
Fix this by calling generic_pipe_buf_release() at the end of
watch_queue_pipe_buf_release().
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit db8facfc9f upstream.
In free_pipe_info(), free the watchqueue state after clearing the pipe
ring as each pipe ring descriptor has a release function, and in the
case of a notification message, this is watch_queue_pipe_buf_release()
which tries to mark the allocation bitmap that was previously released.
Fix this by moving the put of the pipe's ref on the watch queue to after
the ring has been cleared. We still need to call watch_queue_clear()
before doing that to make sure that the pipe is disconnected from any
notification sources first.
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c993ee0f9f upstream.
In watch_queue_set_filter(), there are a couple of places where we check
that the filter type value does not exceed what the type_filter bitmap
can hold. One place calculates the number of bits by:
if (tf[i].type >= sizeof(wfilter->type_filter) * 8)
which is fine, but the second does:
if (tf[i].type >= sizeof(wfilter->type_filter) * BITS_PER_LONG)
which is not. This can lead to a couple of out-of-bounds writes due to
a too-large type:
(1) __set_bit() on wfilter->type_filter
(2) Writing more elements in wfilter->filters[] than we allocated.
Fix this by just using the proper WATCH_TYPE__NR instead, which is the
number of types we actually know about.
The bug may cause an oops looking something like:
BUG: KASAN: slab-out-of-bounds in watch_queue_set_filter+0x659/0x740
Write of size 4 at addr ffff88800d2c66bc by task watch_queue_oob/611
...
Call Trace:
<TASK>
dump_stack_lvl+0x45/0x59
print_address_description.constprop.0+0x1f/0x150
...
kasan_report.cold+0x7f/0x11b
...
watch_queue_set_filter+0x659/0x740
...
__x64_sys_ioctl+0x127/0x190
do_syscall_64+0x43/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
Allocated by task 611:
kasan_save_stack+0x1e/0x40
__kasan_kmalloc+0x81/0xa0
watch_queue_set_filter+0x23a/0x740
__x64_sys_ioctl+0x127/0x190
do_syscall_64+0x43/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
The buggy address belongs to the object at ffff88800d2c66a0
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 28 bytes inside of
32-byte region [ffff88800d2c66a0, ffff88800d2c66c0)
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6c7cb60bff upstream.
When building for Thumb2, the vectors make use of a local label. Sadly,
the Spectre BHB code also uses a local label with the same number which
results in the Thumb2 reference pointing at the wrong place. Fix this
by changing the number used for the Spectre BHB local label.
Fixes: b9baf5c8c5 ("ARM: Spectre-BHB workaround")
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 39bab83b11 upstream.
Only prio 1 is supported for nic mode when there is no ignore flow level
support in firmware. But for switchdev mode, which supports fixed number
of statically pre-allocated prios, this restriction is not relevant so
it can be relaxed.
Fixes: d671e109bd ("net/mlx5: Fix tc max supported prio for nic mode")
Signed-off-by: Dima Chumak <dchumak@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4fa59ede95 upstream.
The feature negotiation was designed in a way that
makes it possible for devices to know which config
fields will be accessed by drivers.
This is broken since commit 404123c2db ("virtio: allow drivers to
validate features") with fallout in at least block and net. We have a
partial work-around in commit 2f9a174f91 ("virtio: write back
F_VERSION_1 before validate") which at least lets devices find out which
format should config space have, but this is a partial fix: guests
should not access config space without acknowledging features since
otherwise we'll never be able to change the config space format.
To fix, split finalize_features from virtio_finalize_features and
call finalize_features with all feature bits before validation,
and then - if validation changed any bits - once again after.
Since virtio_finalize_features no longer writes out features
rename it to virtio_features_ok - since that is what it does:
checks that features are ok with the device.
As a side effect, this also reduces the amount of hypervisor accesses -
we now only acknowledge features once unless we are clearing any
features when validating (which is uncommon).
IRC I think that this was more or less always the intent in the spec but
unfortunately the way the spec is worded does not say this explicitly, I
plan to address this at the spec level, too.
Acked-by: Jason Wang <jasowang@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 404123c2db ("virtio: allow drivers to validate features")
Fixes: 2f9a174f91 ("virtio: write back F_VERSION_1 before validate")
Cc: "Halil Pasic" <pasic@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 838d6d3461 upstream.
virtio_finalize_features is only used internally within virtio.
No reason to export it.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a7cc099f2e upstream.
This looks like a typo in 8f32d5e563. This change didn't intend to do
any functional changes.
The problem was caught by gVisor tests.
Fixes: 8f32d5e563 ("KVM: x86/mmu: allow kvm_faultin_pfn to return page fault handling code")
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Message-Id: <20211015163221.472508-1-avagin@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit aa6f8dcbab upstream.
Unfortunately, we ended up merging an old version of the patch "fix info
leak with DMA_FROM_DEVICE" instead of merging the latest one. Christoph
(the swiotlb maintainer), he asked me to create an incremental fix
(after I have pointed this out the mix up, and asked him for guidance).
So here we go.
The main differences between what we got and what was agreed are:
* swiotlb_sync_single_for_device is also required to do an extra bounce
* We decided not to introduce DMA_ATTR_OVERWRITE until we have exploiters
* The implantation of DMA_ATTR_OVERWRITE is flawed: DMA_ATTR_OVERWRITE
must take precedence over DMA_ATTR_SKIP_CPU_SYNC
Thus this patch removes DMA_ATTR_OVERWRITE, and makes
swiotlb_sync_single_for_device() bounce unconditionally (that is, also
when dir == DMA_TO_DEVICE) in order do avoid synchronising back stale
data from the swiotlb buffer.
Let me note, that if the size used with dma_sync_* API is less than the
size used with dma_[un]map_*, under certain circumstances we may still
end up with swiotlb not being transparent. In that sense, this is no
perfect fix either.
To get this bullet proof, we would have to bounce the entire
mapping/bounce buffer. For that we would have to figure out the starting
address, and the size of the mapping in
swiotlb_sync_single_for_device(). While this does seem possible, there
seems to be no firm consensus on how things are supposed to work.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Fixes: ddbd89deb7 ("swiotlb: fix info leak with DMA_FROM_DEVICE")
Cc: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e2edd6371 upstream.
Commit 18107f8a2d ("arm64: Support execute-only permissions with
Enhanced PAN") re-introduced execute-only permissions when EPAN is
available. When EPAN is not available, arch_filter_pgprot() is supposed
to change a PAGE_EXECONLY permission into PAGE_READONLY_EXEC. However,
if BTI or MTE are present, such check does not detect the execute-only
pgprot in the presence of PTE_GP (BTI) or MT_NORMAL_TAGGED (MTE),
allowing the user to request PROT_EXEC with PROT_BTI or PROT_MTE.
Remove the arch_filter_pgprot() function, change the default VM_EXEC
permissions to PAGE_READONLY_EXEC and update the protection_map[] array
at core_initcall() if EPAN is detected.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Fixes: 18107f8a2d ("arm64: Support execute-only permissions with Enhanced PAN")
Cc: <stable@vger.kernel.org> # 5.13.x
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a1cc1697bb upstream.
Legacy and old PCI I/O based cards do not support 32-bit I/O addressing.
Since commit 64f160e19e ("PCI: aardvark: Configure PCIe resources from
'ranges' DT property") kernel can set different PCIe address on CPU and
different on the bus for the one A37xx address mapping without any firmware
support in case the bus address does not conflict with other A37xx mapping.
So remap I/O space to the bus address 0x0 to enable support for old legacy
I/O port based cards which have hardcoded I/O ports in low address space.
Note that DDR on A37xx is mapped to bus address 0x0. And mapping of I/O
space can be set to address 0x0 too because MEM space and I/O space are
separate and so do not conflict.
Remapping IO space on Turris Mox to different address is not possible to
due bootloader bug.
Signed-off-by: Pali Rohár <pali@kernel.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 76f6386b25 ("arm64: dts: marvell: Add Aardvark PCIe support for Armada 3700")
Cc: stable@vger.kernel.org # 64f160e19e ("PCI: aardvark: Configure PCIe resources from 'ranges' DT property")
Cc: stable@vger.kernel.org # 514ef1e62d ("arm64: dts: marvell: armada-37xx: Extend PCIe MEM space")
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit caf4c86bf1 upstream.
At the moment running osnoise on a nohz_full CPU or uncontested FIFO
priority and a PREEMPT_RCU kernel might have the side effect of
extending grace periods too much. This will entice RCU to force a
context switch on the wayward CPU to end the grace period, all while
introducing unwarranted noise into the tracer. This behaviour is
unavoidable as overly extending grace periods might exhaust the system's
memory.
This same exact problem is what extended quiescent states (EQS) were
created for, conversely, rcu_momentary_dyntick_idle() emulates them by
performing a zero duration EQS. So let's make use of it.
In the common case rcu_momentary_dyntick_idle() is fairly inexpensive:
atomically incrementing a local per-CPU counter and doing a store. So it
shouldn't affect osnoise's measurements (which has a 1us granularity),
so we'll call it unanimously.
The uncommon case involve calling rcu_momentary_dyntick_idle() after
having the osnoise process:
- Receive an expedited quiescent state IPI with preemption disabled or
during an RCU critical section. (activates rdp->cpu_no_qs.b.exp
code-path).
- Being preempted within in an RCU critical section and having the
subsequent outermost rcu_read_unlock() called with interrupts
disabled. (t->rcu_read_unlock_special.b.blocked code-path).
Neither of those are possible at the moment, and are unlikely to be in
the future given the osnoise's loop design. On top of this, the noise
generated by the situations described above is unavoidable, and if not
exposed by rcu_momentary_dyntick_idle() will be eventually seen in
subsequent rcu_read_unlock() calls or schedule operations.
Link: https://lkml.kernel.org/r/20220307180740.577607-1-nsaenzju@redhat.com
Cc: stable@vger.kernel.org
Fixes: bce29ac9ce ("trace: Add osnoise tracer")
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0966d38583 upstream.
RISC-V can do PC-relative jumps with a 32bit range using the following
two instructions:
auipc t0, imm20 ; t0 = PC + imm20 * 2^12
jalr ra, t0, imm12 ; ra = PC + 4, PC = t0 + imm12
Crucially both the 20bit immediate imm20 and the 12bit immediate imm12
are treated as two's-complement signed values. For this reason the
immediates are usually calculated like this:
imm20 = (offset + 0x800) >> 12
imm12 = offset & 0xfff
..where offset is the signed offset from the auipc instruction. When
the 11th bit of offset is 0 the addition of 0x800 doesn't change the top
20 bits and imm12 considered positive. When the 11th bit is 1 the carry
of the addition by 0x800 means imm20 is one higher, but since imm12 is
then considered negative the two's complement representation means it
all cancels out nicely.
However, this addition by 0x800 (2^11) means an offset greater than or
equal to 2^31 - 2^11 would overflow so imm20 is considered negative and
result in a backwards jump. Similarly the lower range of offset is also
moved down by 2^11 and hence the true 32bit range is
[-2^31 - 2^11, 2^31 - 2^11)
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Fixes: e2c0cdfba7 ("RISC-V: User-facing API")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f0d2f15362 upstream.
Currently meson_mmc_post_req() is called in meson_mmc_request() right
after meson_mmc_start_cmd(). This could lead to DMA unmapping before the request
is actually finished.
To fix, don't call meson_mmc_post_req() until meson_mmc_request_done().
Signed-off-by: Rong Chen <rong.chen@amlogic.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Fixes: 79ed05e329 ("mmc: meson-gx: add support for descriptor chain mode")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220216124239.4007667-1-rong.chen@amlogic.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c80ee64a80 upstream.
The alternative mechanism needs runtime code patching, it can't work
on XIP_KERNEL. And the errata workarounds are implemented via the
alternative mechanism. So add !XIP_KERNEL dependency for alternative
and erratas.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Fixes: 44c9225729 ("RISC-V: enable XIP")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0bf476fc36 upstream.
There is an oddity in the way the RSR register flags propagate to the
ISR register (and the actual interrupt output) on this hardware: it
appears that RSR register bits only result in ISR being asserted if the
interrupt was actually enabled at the time, so enabling interrupts with
RSR bits already set doesn't trigger an interrupt to be raised. There
was already a partial fix for this race in the macb_poll function where
it checked for RSR bits being set and re-triggered NAPI receive.
However, there was a still a race window between checking RSR and
actually enabling interrupts, where a lost wakeup could happen. It's
necessary to check again after enabling interrupts to see if RSR was set
just prior to the interrupt being enabled, and re-trigger receive in that
case.
This issue was noticed in a point-to-point UDP request-response protocol
which periodically saw timeouts or abnormally high response times due to
received packets not being processed in a timely fashion. In many
applications, more packets arriving, including TCP retransmissions, would
cause the original packet to be processed, thus masking the issue.
Fixes: 02f7a34f34 ("net: macb: Re-enable RX interrupt only when RX is done")
Cc: stable@vger.kernel.org
Co-developed-by: Scott McNutt <scott.mcnutt@siriusxm.com>
Signed-off-by: Scott McNutt <scott.mcnutt@siriusxm.com>
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fc7f750dc9 upstream.
The netif_rx_ni() function frees the skb so we can't dereference it to
save the skb->len.
Fixes: 61e1210476 ("staging: gdm7240: adding LTE USB driver")
Cc: stable <stable@vger.kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220228074331.GA13685@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8f4347081b upstream.
Commit 54659ca026 ("staging: rtl8723bs: remove possible deadlock when
disconnect (v2)") split the locking of pxmitpriv->lock vs sleep_q/lock
into 2 locks in attempt to fix a lockdep reported issue with the locking
order of the sta_hash_lock vs pxmitpriv->lock.
But in the end this turned out to not fully solve the sta_hash_lock issue
so commit a7ac783c33 ("staging: rtl8723bs: remove a second possible
deadlock") was added to fix this in another way.
The original fix was kept as it was still seen as a good thing to have,
but now it turns out that it creates a deadlock in access-point mode:
[Feb20 23:47] ======================================================
[ +0.074085] WARNING: possible circular locking dependency detected
[ +0.074077] 5.16.0-1-amd64 #1 Tainted: G C E
[ +0.064710] ------------------------------------------------------
[ +0.074075] ksoftirqd/3/29 is trying to acquire lock:
[ +0.060542] ffffb8b30062ab00 (&pxmitpriv->lock){+.-.}-{2:2}, at: rtw_xmit_classifier+0x8a/0x140 [r8723bs]
[ +0.114921]
but task is already holding lock:
[ +0.069908] ffffb8b3007ab704 (&psta->sleep_q.lock){+.-.}-{2:2}, at: wakeup_sta_to_xmit+0x3b/0x300 [r8723bs]
[ +0.116976]
which lock already depends on the new lock.
[ +0.098037]
the existing dependency chain (in reverse order) is:
[ +0.089704]
-> #1 (&psta->sleep_q.lock){+.-.}-{2:2}:
[ +0.077232] _raw_spin_lock_bh+0x34/0x40
[ +0.053261] xmitframe_enqueue_for_sleeping_sta+0xc1/0x2f0 [r8723bs]
[ +0.082572] rtw_xmit+0x58b/0x940 [r8723bs]
[ +0.056528] _rtw_xmit_entry+0xba/0x350 [r8723bs]
[ +0.062755] dev_hard_start_xmit+0xf1/0x320
[ +0.056381] sch_direct_xmit+0x9e/0x360
[ +0.052212] __dev_queue_xmit+0xce4/0x1080
[ +0.055334] ip6_finish_output2+0x18f/0x6e0
[ +0.056378] ndisc_send_skb+0x2c8/0x870
[ +0.052209] ndisc_send_ns+0xd3/0x210
[ +0.050130] addrconf_dad_work+0x3df/0x5a0
[ +0.055338] process_one_work+0x274/0x5a0
[ +0.054296] worker_thread+0x52/0x3b0
[ +0.050124] kthread+0x16c/0x1a0
[ +0.044925] ret_from_fork+0x1f/0x30
[ +0.049092]
-> #0 (&pxmitpriv->lock){+.-.}-{2:2}:
[ +0.074101] __lock_acquire+0x10f5/0x1d80
[ +0.054298] lock_acquire+0xd7/0x300
[ +0.049088] _raw_spin_lock_bh+0x34/0x40
[ +0.053248] rtw_xmit_classifier+0x8a/0x140 [r8723bs]
[ +0.066949] rtw_xmitframe_enqueue+0xa/0x20 [r8723bs]
[ +0.066946] rtl8723bs_hal_xmitframe_enqueue+0x14/0x50 [r8723bs]
[ +0.078386] wakeup_sta_to_xmit+0xa6/0x300 [r8723bs]
[ +0.065903] rtw_recv_entry+0xe36/0x1160 [r8723bs]
[ +0.063809] rtl8723bs_recv_tasklet+0x349/0x6c0 [r8723bs]
[ +0.071093] tasklet_action_common.constprop.0+0xe5/0x110
[ +0.070966] __do_softirq+0x16f/0x50a
[ +0.050134] __irq_exit_rcu+0xeb/0x140
[ +0.051172] irq_exit_rcu+0xa/0x20
[ +0.047006] common_interrupt+0xb8/0xd0
[ +0.052214] asm_common_interrupt+0x1e/0x40
[ +0.056381] finish_task_switch.isra.0+0x100/0x3a0
[ +0.063670] __schedule+0x3ad/0xd20
[ +0.048047] schedule+0x4e/0xc0
[ +0.043880] smpboot_thread_fn+0xc4/0x220
[ +0.054298] kthread+0x16c/0x1a0
[ +0.044922] ret_from_fork+0x1f/0x30
[ +0.049088]
other info that might help us debug this:
[ +0.095950] Possible unsafe locking scenario:
[ +0.070952] CPU0 CPU1
[ +0.054282] ---- ----
[ +0.054285] lock(&psta->sleep_q.lock);
[ +0.047004] lock(&pxmitpriv->lock);
[ +0.074082] lock(&psta->sleep_q.lock);
[ +0.077209] lock(&pxmitpriv->lock);
[ +0.043873]
*** DEADLOCK ***
[ +0.070950] 1 lock held by ksoftirqd/3/29:
[ +0.049082] #0: ffffb8b3007ab704 (&psta->sleep_q.lock){+.-.}-{2:2}, at: wakeup_sta_to_xmit+0x3b/0x300 [r8723bs]
Analysis shows that in hindsight the splitting of the lock was not
a good idea, so revert this to fix the access-point mode deadlock.
Note this is a straight-forward revert done with git revert, the commented
out "/* spin_lock_bh(&psta_bmc->sleep_q.lock); */" lines were part of the
code before the reverted changes.
Fixes: 54659ca026 ("staging: rtl8723bs: remove possible deadlock when disconnect (v2)")
Cc: stable <stable@vger.kernel.org>
Cc: Fabio Aiuto <fabioaiuto83@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215542
Link: https://lore.kernel.org/r/20220302101637.26542-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0c4bcfdecb upstream.
In FOPEN_DIRECT_IO mode, fuse_file_write_iter() calls
fuse_direct_write_iter(), which normally calls fuse_direct_io(), which then
imports the write buffer with fuse_get_user_pages(), which uses
iov_iter_get_pages() to grab references to userspace pages instead of
actually copying memory.
On the filesystem device side, these pages can then either be read to
userspace (via fuse_dev_read()), or splice()d over into a pipe using
fuse_dev_splice_read() as pipe buffers with &nosteal_pipe_buf_ops.
This is wrong because after fuse_dev_do_read() unlocks the FUSE request,
the userspace filesystem can mark the request as completed, causing write()
to return. At that point, the userspace filesystem should no longer have
access to the pipe buffer.
Fix by copying pages coming from the user address space to new pipe
buffers.
Reported-by: Jann Horn <jannh@google.com>
Fixes: c3021629a0 ("fuse: support splice() reading from fuse device")
Cc: <stable@vger.kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a679a61520 upstream.
The fileattr API conversion broke lsattr on ntfs3g.
Previously the ioctl(... FS_IOC_GETFLAGS) returned an EINVAL error, but
after the conversion the error returned by the fuse filesystem was not
propagated back to the ioctl() system call, resulting in success being
returned with bogus values.
Fix by checking for outarg.result in fuse_priv_ioctl(), just as generic
ioctl code does.
Reported-by: Jean-Pierre André <jean-pierre.andre@wanadoo.fr>
Fixes: 72227eac17 ("fuse: convert to fileattr")
Cc: <stable@vger.kernel.org> # v5.13
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6845376713 upstream.
When CONFIG_GENERIC_CPU_VULNERABILITIES is not set, references
to spectre_v2_update_state() cause a build error, so provide an
empty stub for that function when the Kconfig option is not set.
Fixes this build error:
arm-linux-gnueabi-ld: arch/arm/mm/proc-v7-bugs.o: in function `cpu_v7_bugs_init':
proc-v7-bugs.c:(.text+0x52): undefined reference to `spectre_v2_update_state'
arm-linux-gnueabi-ld: proc-v7-bugs.c:(.text+0x82): undefined reference to `spectre_v2_update_state'
Fixes: b9baf5c8c5 ("ARM: Spectre-BHB workaround")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: patches@armlinux.org.uk
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fda153c89a ]
Running the memfd script ./run_hugetlbfs_test.sh will often end in error
as follows:
memfd-hugetlb: CREATE
memfd-hugetlb: BASIC
memfd-hugetlb: SEAL-WRITE
memfd-hugetlb: SEAL-FUTURE-WRITE
memfd-hugetlb: SEAL-SHRINK
fallocate(ALLOC) failed: No space left on device
./run_hugetlbfs_test.sh: line 60: 166855 Aborted (core dumped) ./memfd_test hugetlbfs
opening: ./mnt/memfd
fuse: DONE
If no hugetlb pages have been preallocated, run_hugetlbfs_test.sh will
allocate 'just enough' pages to run the test. In the SEAL-FUTURE-WRITE
test the mfd_fail_write routine maps the file, but does not unmap. As a
result, two hugetlb pages remain reserved for the mapping. When the
fallocate call in the SEAL-SHRINK test attempts allocate all hugetlb
pages, it is short by the two reserved pages.
Fix by making sure to unmap in mfd_fail_write.
Link: https://lkml.kernel.org/r/20220219004340.56478-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dd990352f0 ]
osnoise's runtime and period are in the microseconds scale, but it is
currently sleeping in the millisecond's scale. This behavior roots in the
usage of hwlat as the skeleton for osnoise.
Make osnoise to sleep in the microseconds scale. Also, move the sleep to
a specialized function.
Link: https://lkml.kernel.org/r/302aa6c7bdf2d131719b22901905e9da122a11b2.1645197336.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6c0d8833a6 ]
valid_lft, prefered_lft and tstamp are always accessed under the lock
"lock" in other places. Reading these without taking the lock may result
in inconsistencies regarding the calculation of the valid and preferred
variables since decisions are taken on these fields for those variables.
Signed-off-by: Niels Dossche <dossche.niels@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Niels Dossche <niels.dossche@ugent.be>
Link: https://lore.kernel.org/r/20220223131954.6570-1-niels.dossche@ugent.be
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e8240addd0 ]
This reverts commit 2afeec08ab.
The reasoning in the commit was wrong - the code expected to setup the
watch even if 'hotplug-status' didn't exist. In fact, it relied on the
watch being fired the first time - to check if maybe 'hotplug-status' is
already set to 'connected'. Not registering a watch for non-existing
path (which is the case if hotplug script hasn't been executed yet),
made the backend not waiting for the hotplug script to execute. This in
turns, made the netfront think the interface is fully operational, while
in fact it was not (the vif interface on xen-netback side might not be
configured yet).
This was a workaround for 'hotplug-status' erroneously being removed.
But since that is reverted now, the workaround is not necessary either.
More discussion at
https://lore.kernel.org/xen-devel/afedd7cb-a291-e773-8b0d-4db9b291fa98@ipxe.org/T/#u
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Michael Brown <mbrown@fensystems.co.uk>
Link: https://lore.kernel.org/r/20220222001817.2264967-2-marmarek@invisiblethingslab.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0f4558ae91 ]
This reverts commit 1f2565780e.
The 'hotplug-status' node should not be removed as long as the vif
device remains configured. Otherwise the xen-netback would wait for
re-running the network script even if it was already called (in case of
the frontent re-connecting). But also, it _should_ be removed when the
vif device is destroyed (for example when unbinding the driver) -
otherwise hotplug script would not configure the device whenever it
re-appear.
Moving removal of the 'hotplug-status' node was a workaround for nothing
calling network script after xen-netback module is reloaded. But when
vif interface is re-created (on xen-netback unbind/bind for example),
the script should be called, regardless of who does that - currently
this case is not handled by the toolstack, and requires manual
script call. Keeping hotplug-status=connected to skip the call is wrong
and leads to not configured interface.
More discussion at
https://lore.kernel.org/xen-devel/afedd7cb-a291-e773-8b0d-4db9b291fa98@ipxe.org/T/#u
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Link: https://lore.kernel.org/r/20220222001817.2264967-1-marmarek@invisiblethingslab.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e2b993302f ]
vkms leverages common amdgpu framebuffer creation, and
also as it does not support FB modifier, there is no need
to check tiling flags when initing framebuffer when virtual
display is enabled.
This can fix below calltrace:
amdgpu 0000:00:08.0: GFX9+ requires FB check based on format modifier
WARNING: CPU: 0 PID: 1023 at drivers/gpu/drm/amd/amdgpu/amdgpu_display.c:1150 amdgpu_display_framebuffer_init+0x8e7/0xb40 [amdgpu]
v2: check adev->enable_virtual_display instead as vkms can be
enabled in bare metal as well.
Signed-off-by: Leslie Shi <Yuliang.Shi@amd.com>
Signed-off-by: Guchun Chen <guchun.chen@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ae42f92888 ]
We are racing the registering of .to_irq when probing the
i2c driver. This results in random failure of touchscreen
devices.
Following explains the race condition better.
[gpio driver] gpio driver registers gpio chip
[gpio consumer] gpio is acquired
[gpio consumer] gpiod_to_irq() fails with -ENXIO
[gpio driver] gpio driver registers irqchip
gpiod_to_irq works at this point, but -ENXIO is fatal
We could see the following errors in dmesg logs when gc->to_irq is NULL
[2.101857] i2c_hid i2c-FTS3528:00: HID over i2c has not been provided an Int IRQ
[2.101953] i2c_hid: probe of i2c-FTS3528:00 failed with error -22
To avoid this situation, defer probing until to_irq is registered.
Returning -EPROBE_DEFER would be the first step towards avoiding
the failure of devices due to the race in registration of .to_irq.
Final solution to this issue would be to avoid using gc irq members
until they are fully initialized.
This issue has been reported many times in past and people have been
using workarounds like changing the pinctrl_amd to built-in instead
of loading it as a module or by adding a softdep for pinctrl_amd into
the config file.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=209413
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shreeya Patel <shreeya.patel@collabora.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3f1271b54e ]
There are enough VBIOS escapes without the proper workaround that some
users still hit this. Microsoft never productized ATS on Windows so OEM
platforms that were Windows-only didn't always validate ATS.
The advantages of ATS are not worth it compared to the potential
instabilities on harvested boards. Disable ATS on all Navi10 and Navi14
boards.
Symptoms include:
amdgpu 0000:07:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0007 address=0xffffc02000 flags=0x0000]
AMD-Vi: Event logged [IO_PAGE_FAULT device=07:00.0 domain=0x0007 address=0xffffc02000 flags=0x0000]
[drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring sdma0 timeout, signaled seq=6047, emitted seq=6049
amdgpu 0000:07:00.0: amdgpu: GPU reset begin!
amdgpu 0000:07:00.0: amdgpu: GPU reset succeeded, trying to resume
amdgpu 0000:07:00.0: [drm:amdgpu_ring_test_helper [amdgpu]] *ERROR* ring sdma0 test failed (-110)
[drm:amdgpu_device_ip_resume_phase2 [amdgpu]] *ERROR* resume of IP block <sdma_v4_0> failed -110
amdgpu 0000:07:00.0: amdgpu: GPU reset(1) failed
Related commits:
e8946a53e2 ("PCI: Mark AMD Navi14 GPU ATS as broken")
a2da5d8cc0 ("PCI: Mark AMD Raven iGPU ATS as broken in some platforms")
45beb31d3a ("PCI: Mark AMD Navi10 GPU rev 0x00 ATS as broken")
5e89cd303e ("PCI: Mark AMD Navi14 GPU rev 0xc5 ATS as broken")
d28ca864c4 ("PCI: Mark AMD Stoney Radeon R7 GPU ATS as broken")
9b44b0b09d ("PCI: Mark AMD Stoney GPU ATS as broken")
[bhelgaas: add symptoms and related commits]
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1760
Link: https://lore.kernel.org/r/20220222160801.841643-1-alexander.deucher@amd.com
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Guchun Chen <guchun.chen@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 35f165f089 ]
Almost all fault/warning bits in pmbus status registers remain set even
after fault/warning condition are removed. As per pmbus specification
these faults must be cleared by user.
Modify hwmon behavior to clear fault/warning bit after fetching data if
fault/warning bit was set. This allows to get fresh data in next read.
Signed-off-by: Vikash Chandola <vikash.chandola@linux.intel.com>
Link: https://lore.kernel.org/r/20220222131253.2426834-1-vikash.chandola@linux.intel.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ec756e40e2 ]
Inspired by commit 3553ae5690 (x86/kvm: Don't use pvqspinlock code if
only 1 vCPU), on a VM with only 1 vCPU, there is no need to enable
pv tlb/ipi/sched_yield and we can save the memory for __pv_cpu_mask.
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1645171838-2855-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e40945ab7c ]
On bind we will register the HDMI codec device but we don't unregister
it on unbind, leading to a device leakage. Unregister our device at
unbind.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220127111452.222002-1-maxime@cerno.tech
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 80808768e4 ]
After slave abort, all DMA should be stopped, or it will affect the
next transmission and maybe abort again.
Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
Link: https://lore.kernel.org/r/20220216014028.8123-3-jon.lin@rock-chips.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3a55f72924 ]
If vcpu has tsc_always_catchup set each request updates pvclock data.
KVM_HC_CLOCK_PAIRING consumers such as ptp_kvm_x86 rely on tsc read on
host's side and do hypercall inside pvclock_read_retry loop leading to
infinite loop in such situation.
v3:
Removed warn
Changed return code to KVM_EFAULT
v2:
Added warn
Signed-off-by: Anton Romanov <romanton@google.com>
Message-Id: <20220216182653.506850-1-romanton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4cb9a998b1 ]
I saw the below splatting after the host suspended and resumed.
WARNING: CPU: 0 PID: 2943 at kvm/arch/x86/kvm/../../../virt/kvm/kvm_main.c:5531 kvm_resume+0x2c/0x30 [kvm]
CPU: 0 PID: 2943 Comm: step_after_susp Tainted: G W IOE 5.17.0-rc3+ #4
RIP: 0010:kvm_resume+0x2c/0x30 [kvm]
Call Trace:
<TASK>
syscore_resume+0x90/0x340
suspend_devices_and_enter+0xaee/0xe90
pm_suspend.cold+0x36b/0x3c2
state_store+0x82/0xf0
kernfs_fop_write_iter+0x1b6/0x260
new_sync_write+0x258/0x370
vfs_write+0x33f/0x510
ksys_write+0xc9/0x160
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
lockdep_is_held() can return -1 when lockdep is disabled which triggers
this warning. Let's use lockdep_assert_not_held() which can detect
incorrect calls while holding a lock and it also avoids false negatives
when lockdep is disabled.
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1644920142-81249-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6f66db29e2 ]
It appears that last minute change moved ACPI ID of Alder Lake-M
to the INTC1055, which is already in the driver.
This ID on the other hand will be used elsewhere.
This reverts commit 258435a1c8.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ddbd89deb7 ]
The problem I'm addressing was discovered by the LTP test covering
cve-2018-1000204.
A short description of what happens follows:
1) The test case issues a command code 00 (TEST UNIT READY) via the SG_IO
interface with: dxfer_len == 524288, dxdfer_dir == SG_DXFER_FROM_DEV
and a corresponding dxferp. The peculiar thing about this is that TUR
is not reading from the device.
2) In sg_start_req() the invocation of blk_rq_map_user() effectively
bounces the user-space buffer. As if the device was to transfer into
it. Since commit a45b599ad8 ("scsi: sg: allocate with __GFP_ZERO in
sg_build_indirect()") we make sure this first bounce buffer is
allocated with GFP_ZERO.
3) For the rest of the story we keep ignoring that we have a TUR, so the
device won't touch the buffer we prepare as if the we had a
DMA_FROM_DEVICE type of situation. My setup uses a virtio-scsi device
and the buffer allocated by SG is mapped by the function
virtqueue_add_split() which uses DMA_FROM_DEVICE for the "in" sgs (here
scatter-gather and not scsi generics). This mapping involves bouncing
via the swiotlb (we need swiotlb to do virtio in protected guest like
s390 Secure Execution, or AMD SEV).
4) When the SCSI TUR is done, we first copy back the content of the second
(that is swiotlb) bounce buffer (which most likely contains some
previous IO data), to the first bounce buffer, which contains all
zeros. Then we copy back the content of the first bounce buffer to
the user-space buffer.
5) The test case detects that the buffer, which it zero-initialized,
ain't all zeros and fails.
One can argue that this is an swiotlb problem, because without swiotlb
we leak all zeros, and the swiotlb should be transparent in a sense that
it does not affect the outcome (if all other participants are well
behaved).
Copying the content of the original buffer into the swiotlb buffer is
the only way I can think of to make swiotlb transparent in such
scenarios. So let's do just that if in doubt, but allow the driver
to tell us that the whole mapped buffer is going to be overwritten,
in which case we can preserve the old behavior and avoid the performance
impact of the extra bounce.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
