With commit eaa7995c529b54 (regulator: core: avoid
regulator_resolve_supply() race condition) we started holding the rdev
lock while resolving supplies, an operation that requires holding the
regulator_list_mutex. This results in lockdep warnings since in other
places we take the list mutex then the mutex on an individual rdev.
Since the goal is to make sure that we don't call set_supply() twice
rather than a concern about the cost of resolution pull the rdev lock
and check for duplicate resolution down to immediately before we do the
set_supply() and drop it again once the allocation is done.
Fixes: eaa7995c529b54 (regulator: core: avoid regulator_resolve_supply() race condition) Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20210122132042.10306-1-broonie@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
At the end of regulator_resolve_supply() we have historically turned
on our supply in some cases. This could be for one of two reasons:
1. If resolving supplies was happening before the call to
set_machine_constraints() we needed to predict if
set_machine_constraints() was going to turn the regulator on and we
needed to preemptively turn the supply on.
2. Maybe set_machine_constraints() happened before we could resolve
supplies (because we failed the first time to resolve) and thus we
might need to propagate an enable that already happened up to our
supply.
Historically regulator_resolve_supply() used _regulator_is_enabled()
to decide whether to turn on the supply.
Let's change things a little bit. Specifically:
1. Let's try to enable the supply and the regulator in the same place,
both in set_machine_constraints(). This means that we have exactly
the same logic for enabling the supply and the regulator.
2. Let's properly set use_count when we enable always-on or boot-on
regulators even for those that don't have supplies. The previous
commit 1fc12b05895e ("regulator: core: Avoid propagating to
supplies when possible") only did this right for regulators with
supplies.
3. Let's make it clear that the only time we need to enable the supply
in regulator_resolve_supply() is if the main regulator is currently
in use. By using use_count (like the rest of the code) to decide
if we're going to enable our supply we keep everything consistent.
Overall the new scheme should be cleaner and easier to reason about.
In addition to fixing regulator_summary to be more correct (because of
the more correct use_count), this change also has the effect of no
longer using _regulator_is_enabled() in this code path.
_regulator_is_enabled() could return an error code for some regulators
at bootup (like RPMh) that can't read their initial state. While one
can argue that the design of those regulators is sub-optimal, the new
logic sidesteps this brokenness. This fix in particular fixes
observed problems on Qualcomm sdm845 boards which use the
above-mentioned RPMh regulator. Those problems were made worse by
commit 1fc12b05895e ("regulator: core: Avoid propagating to supplies
when possible") because now we'd think at bootup that the SD
regulators were already enabled and we'd never try them again.
Fixes: 1fc12b05895e ("regulator: core: Avoid propagating to supplies when possible") Reported-by: Evan Green <evgreen@chromium.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
When a regulator is marked as always on, it is enabled early on, when
checking and setting up constraints. It makes the assumption that the
bootloader properly initialized the regulator, and just in case enables
the regulator anyway.
Some constraints however currently get missed, such as the soft-start
and ramp-delay. This causes the regulator to be enabled, without the
soft-start and ramp-delay being applied, which in turn can cause
high-currents or other start-up problems.
By moving the always-enabled constraints later in the constraints check,
we can at least ensure all constraints for the regulator are followed.
Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Priit Laes <plaes@plaes.org> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Sysbot has reported a warning where a kmalloc() attempt exceeds the
maximum limit. This has been identified as corruption of the xattr_ids
count when reading the xattr id lookup table.
This patch adds a number of additional sanity checks to detect this
corruption and others.
1. It checks for a corrupted xattr index read from the inode. This could
be because the metadata block is uncompressed, or because the
"compression" bit has been corrupted (turning a compressed block
into an uncompressed block). This would cause an out of bounds read.
2. It checks against corruption of the xattr_ids count. This can either
lead to the above kmalloc failure, or a smaller than expected
table to be read.
3. It checks the contents of the index table for corruption.
Sysbot has reported an "slab-out-of-bounds read" error which has been
identified as being caused by a corrupted "ino_num" value read from the
inode. This could be because the metadata block is uncompressed, or
because the "compression" bit has been corrupted (turning a compressed
block into an uncompressed block).
This patch adds additional sanity checks to detect this, and the
following corruption.
1. It checks against corruption of the inodes count. This can either
lead to a larger table to be read, or a smaller than expected
table to be read.
In the case of a too large inodes count, this would often have been
trapped by the existing sanity checks, but this patch introduces
a more exact check, which can identify too small values.
2. It checks the contents of the index table for corruption.
Sysbot has reported a number of "slab-out-of-bounds reads" and
"use-after-free read" errors which has been identified as being caused
by a corrupted index value read from the inode. This could be because
the metadata block is uncompressed, or because the "compression" bit has
been corrupted (turning a compressed block into an uncompressed block).
This patch adds additional sanity checks to detect this, and the
following corruption.
1. It checks against corruption of the ids count. This can either
lead to a larger table to be read, or a smaller than expected
table to be read.
In the case of a too large ids count, this would often have been
trapped by the existing sanity checks, but this patch introduces
a more exact check, which can identify too small values.
2. It checks the contents of the index table for corruption.
blk_mq_map_swqueue() is called from blk_mq_init_allocated_queue()
and blk_mq_update_nr_hw_queues(). For the former caller, the kobject
isn't exposed to userspace yet. For the latter caller, hctx sysfs entries
and debugfs are un-registered before updating nr_hw_queues.
On the other hand, commit 2f8f1336a48b ("blk-mq: always free hctx after
request queue is freed") moves freeing hctx into queue's release
handler, so there won't be race with queue release path too.
So don't hold q->sysfs_lock in blk_mq_map_swqueue().
Cc: Christoph Hellwig <hch@infradead.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
q->sysfs_lock must be held to provide mutual exclusion between
elevator_switch() and here.
Which is simply wrong. elevator_init_mq() is only called from
blk_mq_init_allocated_queue, which is always called before the request
queue is registered via blk_register_queue(), for dm-rq or normal rq
based driver. However, queue's kobject is only exposed and added to sysfs
in blk_register_queue(). So there isn't such race between elevator_switch()
and elevator_init_mq().
So avoid to hold q->sysfs_lock in elevator_init_mq().
Cc: Christoph Hellwig <hch@infradead.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Grab kvm->lock before pinning memory when registering an encrypted
region; sev_pin_memory() relies on kvm->lock being held to ensure
correctness when checking and updating the number of pinned pages.
Add a lockdep assertion to help prevent future regressions.
Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: x86@kernel.org Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org Fixes: 1e80fdc09d12 ("KVM: SVM: Pin guest memory when SEV is active") Signed-off-by: Peter Gonda <pgonda@google.com>
V2
- Fix up patch description
- Correct file paths svm.c -> sev.c
- Add unlock of kvm->lock on sev_pin_memory error
Without memcg, there is a one-to-one mapping between the bdi and
bdi_writeback structures. In this world, things are fairly
straightforward; the first thing bdi_unregister() does is to shutdown
the bdi_writeback structure (or wb), and part of that writeback ensures
that no other work queued against the wb, and that the wb is fully
drained.
With memcg, however, there is a one-to-many relationship between the bdi
and bdi_writeback structures; that is, there are multiple wb objects
which can all point to a single bdi. There is a refcount which prevents
the bdi object from being released (and hence, unregistered). So in
theory, the bdi_unregister() *should* only get called once its refcount
goes to zero (bdi_put will drop the refcount, and when it is zero,
release_bdi gets called, which calls bdi_unregister).
Unfortunately, del_gendisk() in block/gen_hd.c never got the memo about
the Brave New memcg World, and calls bdi_unregister directly. It does
this without informing the file system, or the memcg code, or anything
else. This causes the root wb associated with the bdi to be
unregistered, but none of the memcg-specific wb's are shutdown. So when
one of these wb's are woken up to do delayed work, they try to
dereference their wb->bdi->dev to fetch the device name, but
unfortunately bdi->dev is now NULL, thanks to the bdi_unregister()
called by del_gendisk(). As a result, *boom*.
Fortunately, it looks like the rest of the writeback path is perfectly
happy with bdi->dev and bdi->owner being NULL, so the simplest fix is to
create a bdi_dev_name() function which can handle bdi->dev being NULL.
This also allows us to bulletproof the writeback tracepoints to prevent
them from dereferencing a NULL pointer and crashing the kernel if one is
tracing with memcg's enabled, and an iSCSI device dies or a USB storage
stick is pulled.
The most common way of triggering this will be hotremoval of a device
while writeback with memcg enabled is going on. It was triggering
several times a day in a heavily loaded production environment.
In file included from ./arch/powerpc/include/asm/paca.h:15,
from ./arch/powerpc/include/asm/current.h:13,
from ./include/linux/thread_info.h:21,
from ./include/asm-generic/preempt.h:5,
from ./arch/powerpc/include/generated/asm/preempt.h:1,
from ./include/linux/preempt.h:78,
from ./include/linux/spinlock.h:51,
from fs/fs-writeback.c:19:
In function 'strncpy',
inlined from 'perf_trace_writeback_page_template' at
./include/trace/events/writeback.h:56:1:
./include/linux/string.h:260:9: warning: '__builtin_strncpy' specified
bound 32 equals destination size [-Wstringop-truncation]
return __builtin_strncpy(p, q, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix it by using the new strscpy_pad() which was introduced in "lib/string:
Add strscpy_pad() function" and will always be NUL-terminated instead of
strncpy(). Also, change strlcpy() to use strscpy_pad() in this file for
consistency.
Link: http://lkml.kernel.org/r/1564075099-27750-1-git-send-email-cai@lca.pw Fixes: 455b2864686d ("writeback: Initial tracing support") Fixes: 028c2dd184c0 ("writeback: Add tracing to balance_dirty_pages") Fixes: e84d0a4f8e39 ("writeback: trace event writeback_queue_io") Fixes: b48c104d2211 ("writeback: trace event bdi_dirty_ratelimit") Fixes: cc1676d917f3 ("writeback: Move requeueing when I_SYNC set to writeback_sb_inodes()") Fixes: 9fb0a7da0c52 ("writeback: add more tracepoints") Signed-off-by: Qian Cai <cai@lca.pw> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Tobin C. Harding <tobin@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Dave Chinner <dchinner@redhat.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Nitin Gote <nitin.r.gote@intel.com> Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Cc: Stephen Kitt <steve@sk2.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>
We have a function to copy strings safely and we have a function to copy
strings and zero the tail of the destination (if source string is
shorter than destination buffer) but we do not have a function to do
both at once. This means developers must write this themselves if they
desire this functionality. This is a chore, and also leaves us open to
off by one errors unnecessarily.
Add a function that calls strscpy() then memset()s the tail to zero if
the source string is shorter than the destination buffer.
When handling an auth_gss downcall, it's possible to get 0-length
opaque object for the acceptor. In the case of a 0-length XDR
object, make sure simple_get_netobj() fills in dest->data = NULL,
and does not continue to kmemdup() which will set
dest->data = ZERO_SIZE_PTR for the acceptor.
The trace event code can handle NULL but not ZERO_SIZE_PTR for a
string, and so without this patch the rpcgss_context trace event
will crash the kernel as follows:
Remove duplicated helper functions to parse opaque XDR objects
and place inside new file net/sunrpc/auth_gss/auth_gss_internal.h.
In the new file carry the license and copyright from the source file
net/sunrpc/auth_gss/auth_gss.c. Finally, update the comment inside
include/linux/sunrpc/xdr.h since lockd is not the only user of
struct xdr_netobj.
If we get into a problem severe enough to attempt a reprobe,
we schedule a worker to do that. However, if the problem gets
more severe and the device is actually destroyed before this
worker has a chance to run, we use a free device. Bump up the
reference count of the device until the worker runs to avoid
this situation.
If the server returns a new stateid that does not match the one in our
cache, then try to return the one we hold instead of just invalidating
it on the client side. This ensures that both client and server will
agree that the stateid is invalid.
The final step in regulator_register() is to call
regulator_resolve_supply() for each registered regulator
(including the one in the process of being registered). The
regulator_resolve_supply() function first checks if rdev->supply
is NULL, then it performs various steps to try to find the supply.
If successful, rdev->supply is set inside of set_supply().
This procedure can encounter a race condition if two concurrent
tasks call regulator_register() near to each other on separate CPUs
and one of the regulators has rdev->supply_name specified. There
is currently nothing guaranteeing atomicity between the rdev->supply
check and set steps. Thus, both tasks can observe rdev->supply==NULL
in their regulator_resolve_supply() calls. This then results in
both creating a struct regulator for the supply. One ends up
actually stored in rdev->supply and the other is lost (though still
present in the supply's consumer_list).
Here is a kernel log snippet showing the issue:
[ 12.421768] gpu_cc_gx_gdsc: supplied by pm8350_s5_level
[ 12.425854] gpu_cc_gx_gdsc: supplied by pm8350_s5_level
[ 12.429064] debugfs: Directory 'regulator.4-SUPPLY' with parent
'17a00000.rsc:rpmh-regulator-gfxlvl-pm8350_s5_level'
already present!
Avoid this race condition by holding the rdev->mutex lock inside
of regulator_resolve_supply() while checking and setting
rdev->supply.
xfrm_probe_algs() probes kernel crypto modules and changes the
availability of struct xfrm_algo_desc. But there is a small window
where ealg->available and aalg->available get changed between
count_ah_combs()/count_esp_combs() and dump_ah_combs()/dump_esp_combs(),
in this case we may allocate a smaller skb but later put a larger
amount of data and trigger the panic in skb_put().
Fix this by relaxing the checks when counting the size, that is,
skipping the test of ->available. We may waste some memory for a few
of sizeof(struct sadb_comb), but it is still much better than a panic.
The following mem abort is observed when the mba firmware size exceeds
the allocated mba region. MBA firmware size is restricted to a maximum
size of 1M and remaining memory region is used by modem debug policy
firmware when available. Hence verify whether the MBA firmware size lies
within the allocated memory region and is not greater than 1M before
loading.
Err Logs:
Unable to handle kernel paging request at virtual address
Mem abort info:
...
Call trace:
__memcpy+0x110/0x180
rproc_start+0x40/0x218
rproc_boot+0x5b4/0x608
state_store+0x54/0xf8
dev_attr_store+0x44/0x60
sysfs_kf_write+0x58/0x80
kernfs_fop_write+0x140/0x230
vfs_write+0xc4/0x208
ksys_write+0x74/0xf8
__arm64_sys_write+0x24/0x30
...
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Fixes: 051fb70fd4ea4 ("remoteproc: qcom: Driver for the self-authenticating Hexagon v5") Cc: stable@vger.kernel.org Signed-off-by: Sibi Sankar <sibis@codeaurora.org> Link: https://lore.kernel.org/r/20200722201047.12975-2-sibis@codeaurora.org Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[sudip: manual backport to old file path] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The following mem abort is observed when one of the modem blob firmware
size exceeds the allocated mpss region. Fix this by restricting the copy
size to segment size using request_firmware_into_buf before load.
Err Logs:
Unable to handle kernel paging request at virtual address
Mem abort info:
...
Call trace:
__memcpy+0x110/0x180
rproc_start+0xd0/0x190
rproc_boot+0x404/0x550
state_store+0x54/0xf8
dev_attr_store+0x44/0x60
sysfs_kf_write+0x58/0x80
kernfs_fop_write+0x140/0x230
vfs_write+0xc4/0x208
ksys_write+0x74/0xf8
...
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Fixes: 051fb70fd4ea4 ("remoteproc: qcom: Driver for the self-authenticating Hexagon v5") Cc: stable@vger.kernel.org Signed-off-by: Sibi Sankar <sibis@codeaurora.org> Link: https://lore.kernel.org/r/20200722201047.12975-3-sibis@codeaurora.org Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[sudip: manual backport to old file path] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On some archs, the idle task can call into cpu_suspend(). The cpu_suspend()
will disable or pause function graph tracing, as there's some paths in
bringing down the CPU that can have issues with its return address being
modified. The task_struct structure has a "tracing_graph_pause" atomic
counter, that when set to something other than zero, the function graph
tracer will not modify the return address.
The problem is that the tracing_graph_pause counter is initialized when the
function graph tracer is enabled. This can corrupt the counter for the idle
task if it is suspended in these architectures.
CPU 1 CPU 2
----- -----
do_idle()
cpu_suspend()
pause_graph_tracing()
task_struct->tracing_graph_pause++ (0 -> 1)
If __device_add_disk-->bdi_register_owner-->bdi_register-->
bdi_register_va-->device_create_vargs fails, bdi->dev is still
NULL, __device_add_disk-->register_disk will visit bdi->dev->kobj.
This patch fixes that.
Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Fix kprobe_on_func_entry() returns error code instead of false so that
register_kretprobe() can return an appropriate error code.
append_trace_kprobe() expects the kprobe registration returns -ENOENT
when the target symbol is not found, and it checks whether the target
module is unloaded or not. If the target module doesn't exist, it
defers to probe the target symbol until the module is loaded.
However, since register_kretprobe() returns -EINVAL instead of -ENOENT
in that case, it always fail on putting the kretprobe event on unloaded
modules. e.g.
Kprobe event:
/sys/kernel/debug/tracing # echo p xfs:xfs_end_io >> kprobe_events
[ 16.515574] trace_kprobe: This probe might be able to register after target module is loaded. Continue.
To fix this bug, change kprobe_on_func_entry() to detect symbol lookup
failure and return -ENOENT in that case. Otherwise it returns -EINVAL
or 0 (succeeded, given address is on the entry).
Having multiple destination ports for a unicast address does not make
sense.
Make port_db_load_purge override existent unicast portvec instead of
adding a new port bit.
Fixes: 884729399260 ("net: dsa: mv88e6xxx: handle multiple ports in ATU") Signed-off-by: DENG Qingfang <dqfext@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20210130134334.10243-1-dqfext@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dev->hard_header_len for tunnel interface is set only when header_ops
are set too and already contains full overhead of any tunnel encapsulation.
That's why there is not need to use this overhead twice in mtu calc.
Fixes: fdafed459998 ("ip_gre: set dev->hard_header_len and dev->needed_headroom properly") Reported-by: Slava Bacherikov <mail@slava.cc> Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Link: https://lore.kernel.org/r/1611959267-20536-1-git-send-email-vfedorenko@novek.ru Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One customer reports a crash problem which causes by flush request. It
triggers a warning before crash.
/* new request after previous flush is completed */
if (ktime_after(req_start, mddev->prev_flush_start)) {
WARN_ON(mddev->flush_bio);
mddev->flush_bio = bio;
bio = NULL;
}
The WARN_ON is triggered. We use spin lock to protect prev_flush_start and
flush_bio in md_flush_request. But there is no lock protection in
md_submit_flush_data. It can set flush_bio to NULL first because of
compiler reordering write instructions.
For example, flush bio1 sets flush bio to NULL first in
md_submit_flush_data. An interrupt or vmware causing an extended stall
happen between updating flush_bio and prev_flush_start. Because flush_bio
is NULL, flush bio2 can get the lock and submit to underlayer disks. Then
flush bio1 updates prev_flush_start after the interrupt or extended stall.
Then flush bio3 enters in md_flush_request. The start time req_start is
behind prev_flush_start. The flush_bio is not NULL(flush bio2 hasn't
finished). So it can trigger the WARN_ON now. Then it calls INIT_WORK
again. INIT_WORK() will re-initialize the list pointers in the
work_struct, which then can result in a corrupted work list and the
work_struct queued a second time. With the work list corrupted, it can
lead in invalid work items being used and cause a crash in
process_one_work.
We need to make sure only one flush bio can be handled at one same time.
So add spin lock in md_submit_flush_data to protect prev_flush_start and
flush_bio in an atomic way.
Reviewed-by: David Jeffery <djeffery@redhat.com> Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When an Intel IOMMU is virtualized, and a physical device is
passed-through to the VM, changes of the virtual IOMMU need to be
propagated to the physical IOMMU. The hypervisor therefore needs to
monitor PTE mappings in the IOMMU page-tables. Intel specifications
provide "caching-mode" capability that a virtual IOMMU uses to report
that the IOMMU is virtualized and a TLB flush is needed after mapping to
allow the hypervisor to propagate virtual IOMMU mappings to the physical
IOMMU. To the best of my knowledge no real physical IOMMU reports
"caching-mode" as turned on.
Synchronizing the virtual and the physical IOMMU tables is expensive if
the hypervisor is unaware which PTEs have changed, as the hypervisor is
required to walk all the virtualized tables and look for changes.
Consequently, domain flushes are much more expensive than page-specific
flushes on virtualized IOMMUs with passthrough devices. The kernel
therefore exploited the "caching-mode" indication to avoid domain
flushing and use page-specific flushing in virtualized environments. See
commit 78d5f0f500e6 ("intel-iommu: Avoid global flushes with caching
mode.")
This behavior changed after commit 13cf01744608 ("iommu/vt-d: Make use
of iova deferred flushing"). Now, when batched TLB flushing is used (the
default), full TLB domain flushes are performed frequently, requiring
the hypervisor to perform expensive synchronization between the virtual
TLB and the physical one.
Getting batched TLB flushes to use page-specific invalidations again in
such circumstances is not easy, since the TLB invalidation scheme
assumes that "full" domain TLB flushes are performed for scalability.
Disable batched TLB flushes when caching-mode is on, as the performance
benefit from using batched TLB invalidations is likely to be much
smaller than the overhead of the virtual-to-physical IOMMU page-tables
synchronization.
Fixes: 13cf01744608 ("iommu/vt-d: Make use of iova deferred flushing") Signed-off-by: Nadav Amit <namit@vmware.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Lu Baolu <baolu.lu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Will Deacon <will@kernel.org> Cc: stable@vger.kernel.org Acked-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20210127175317.1600473-1-namit@vmware.com Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Jan Kiszka reported that the x2apic_wrmsr_fence() function uses a plain
MFENCE while the Intel SDM (10.12.3 MSR Access in x2APIC Mode) calls for
MFENCE; LFENCE.
Short summary: we have special MSRs that have weaker ordering than all
the rest. Add fencing consistent with current SDM recommendations.
This is not known to cause any issues in practice, only in theory.
Longer story below:
The reason the kernel uses a different semantic is that the SDM changed
(roughly in late 2017). The SDM changed because folks at Intel were
auditing all of the recommended fences in the SDM and realized that the
x2apic fences were insufficient.
Why was the pain MFENCE judged insufficient?
WRMSR itself is normally a serializing instruction. No fences are needed
because the instruction itself serializes everything.
But, there are explicit exceptions for this serializing behavior written
into the WRMSR instruction documentation for two classes of MSRs:
IA32_TSC_DEADLINE and the X2APIC MSRs.
Back to x2apic: WRMSR is *not* serializing in this specific case.
But why is MFENCE insufficient? MFENCE makes writes visible, but
only affects load/store instructions. WRMSR is unfortunately not a
load/store instruction and is unaffected by MFENCE. This means that a
non-serializing WRMSR could be reordered by the CPU to execute before
the writes made visible by the MFENCE have even occurred in the first
place.
This means that an x2apic IPI could theoretically be triggered before
there is any (visible) data to process.
Does this affect anything in practice? I honestly don't know. It seems
quite possible that by the time an interrupt gets to consume the (not
yet) MFENCE'd data, it has become visible, mostly by accident.
To be safe, add the SDM-recommended fences for all x2apic WRMSRs.
This also leaves open the question of the _other_ weakly-ordered WRMSR:
MSR_IA32_TSC_DEADLINE. While it has the same ordering architecture as
the x2APIC MSRs, it seems substantially less likely to be a problem in
practice. While writes to the in-memory Local Vector Table (LVT) might
theoretically be reordered with respect to a weakly-ordered WRMSR like
TSC_DEADLINE, the SDM has this to say:
In x2APIC mode, the WRMSR instruction is used to write to the LVT
entry. The processor ensures the ordering of this write and any
subsequent WRMSR to the deadline; no fencing is required.
But, that might still leave xAPIC exposed. The safest thing to do for
now is to add the extra, recommended LFENCE.
[ bp: Massage commit message, fix typos, drop accidentally added
newline to tools/arch/x86/include/asm/barrier.h. ]
Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200305174708.F77040DD@viggo.jf.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With retpolines disabled, some configurations of GCC, and specifically
the GCC versions 9 and 10 in Ubuntu will add Intel CET instrumentation
to the kernel by default. That breaks certain tracing scenarios by
adding a superfluous ENDBR64 instruction before the fentry call, for
functions which can be called indirectly.
CET instrumentation isn't currently necessary in the kernel, as CET is
only supported in user space. Disable it unconditionally and move it
into the x86's Makefile as CET/CFI... enablement should be a per-arch
decision anyway.
[ bp: Massage and extend commit message. ]
Fixes: 29be86d7f9cb ("kbuild: add -fcf-protection=none when using retpoline flags") Reported-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Tested-by: Nikolay Borisov <nborisov@suse.com> Cc: <stable@vger.kernel.org> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Link: https://lkml.kernel.org/r/20210128215219.6kct3h2eiustncws@treble Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sergey reported deadlock between kswapd correctly doing its usual
lock_page(page) followed by down_read(page->mapping->i_mmap_rwsem), and
madvise(MADV_REMOVE) on an madvise(MADV_HUGEPAGE) area doing
down_write(page->mapping->i_mmap_rwsem) followed by lock_page(page).
This happened when shmem_fallocate(punch hole)'s unmap_mapping_range()
reaches zap_pmd_range()'s call to __split_huge_pmd(). The same deadlock
could occur when partially truncating a mapped huge tmpfs file, or using
fallocate(FALLOC_FL_PUNCH_HOLE) on it.
__split_huge_pmd()'s page lock was added in 5.8, to make sure that any
concurrent use of reuse_swap_page() (holding page lock) could not catch
the anon THP's mapcounts and swapcounts while they were being split.
Fortunately, reuse_swap_page() is never applied to a shmem or file THP
(not even by khugepaged, which checks PageSwapCache before calling), and
anonymous THPs are never created in shmem or file areas: so that
__split_huge_pmd()'s page lock can only be necessary for anonymous THPs,
on which there is no risk of deadlock with i_mmap_rwsem.
Link: https://lkml.kernel.org/r/alpine.LSU.2.11.2101161409470.2022@eggly.anvils Fixes: c444eb564fb1 ("mm: thp: make the THP mapcount atomic against __split_huge_pmd_locked()") Signed-off-by: Hugh Dickins <hughd@google.com> Reported-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The page_huge_active() can be called from scan_movable_pages() which do
not hold a reference count to the HugeTLB page. So when we call
page_huge_active() from scan_movable_pages(), the HugeTLB page can be
freed parallel. Then we will trigger a BUG_ON which is in the
page_huge_active() when CONFIG_DEBUG_VM is enabled. Just remove the
VM_BUG_ON_PAGE.
Link: https://lkml.kernel.org/r/20210115124942.46403-6-songmuchun@bytedance.com Fixes: 7e1f049efb86 ("mm: hugetlb: cleanup using paeg_huge_active()") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we isolate a HugeTLB page on CPU0. Meanwhile, we free it to the
buddy allocator on CPU1. Then, we can trigger a BUG_ON on CPU0, because
it is already freed to the buddy allocator.
Link: https://lkml.kernel.org/r/20210115124942.46403-5-songmuchun@bytedance.com Fixes: c8721bbbdd36 ("mm: memory-hotplug: enable memory hotplug to handle hugepage") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a race condition between __free_huge_page()
and dissolve_free_huge_page().
CPU0: CPU1:
// page_count(page) == 1
put_page(page)
__free_huge_page(page)
dissolve_free_huge_page(page)
spin_lock(&hugetlb_lock)
// PageHuge(page) && !page_count(page)
update_and_free_page(page)
// page is freed to the buddy
spin_unlock(&hugetlb_lock)
spin_lock(&hugetlb_lock)
clear_page_huge_active(page)
enqueue_huge_page(page)
// It is wrong, the page is already freed
spin_unlock(&hugetlb_lock)
The race window is between put_page() and dissolve_free_huge_page().
We should make sure that the page is already on the free list when it is
dissolved.
As a result __free_huge_page would corrupt page(s) already in the buddy
allocator.
Link: https://lkml.kernel.org/r/20210115124942.46403-4-songmuchun@bytedance.com Fixes: c8721bbbdd36 ("mm: memory-hotplug: enable memory hotplug to handle hugepage") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Hildenbrand <david@redhat.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a new hugetlb page is allocated during fallocate it will not be
marked as active (set_page_huge_active) which will result in a later
isolate_huge_page failure when the page migration code would like to
move that page. Such a failure would be unexpected and wrong.
Only export set_page_huge_active, just leave clear_page_huge_active as
static. Because there are no external users.
Link: https://lkml.kernel.org/r/20210115124942.46403-3-songmuchun@bytedance.com Fixes: 70c3547e36f5 (hugetlbfs: add hugetlbfs_fallocate()) Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Building with gcc 4.9.2 reveals a latent bug in the PCI accessors
for Footbridge platforms, which causes a fatal alignment fault
while accessing IO memory. Fix this by making the assembly volatile.
Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't let KVM load when running as an SEV guest, regardless of what
CPUID says. Memory is encrypted with a key that is not accessible to
the host (L0), thus it's impossible for L0 to emulate SVM, e.g. it'll
see garbage when reading the VMCB.
Technically, KVM could decrypt all memory that needs to be accessible to
the L0 and use shadow paging so that L0 does not need to shadow NPT, but
exposing such information to L0 largely defeats the purpose of running as
an SEV guest. This can always be revisited if someone comes up with a
use case for running VMs inside SEV guests.
Note, VMLOAD, VMRUN, etc... will also #GP on GPAs with C-bit set, i.e. KVM
is doomed even if the SEV guest is debuggable and the hypervisor is willing
to decrypt the VMCB. This may or may not be fixed on CPUs that have the
SVME_ADDR_CHK fix.
Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210202212017.2486595-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some Kingston A2000 NVMe SSDs sooner or later get confused and stop
working when they use the deepest APST sleep while running Linux. The
system then crashes and one has to cold boot it to get the SSD working
again.
Kingston seems to known about this since at least mid-September 2020:
https://bbs.archlinux.org/viewtopic.php?pid=1926994#p1926994
Someone working for a German company representing Kingston to the German
press confirmed to me Kingston engineering is aware of the issue and
investigating; the person stated that to their current knowledge only
the deepest APST sleep state causes trouble. Therefore, make Linux avoid
it for now by applying the NVME_QUIRK_NO_DEEPEST_PS to this SSD.
I have two such SSDs, but it seems the problem doesn't occur with them.
I hence couldn't verify if this patch really fixes the problem, but all
the data in front of me suggests it should.
This patch can easily be reverted or improved upon if a better solution
surfaces.
FWIW, there are many reports about the issue scattered around the web;
most of the users disabled APST completely to make things work, some
just made Linux avoid the deepest sleep state:
While addressing some warnings generated by -Warray-bounds, I found this
bug that was introduced back in 2017:
CC [M] fs/cifs/smb2pdu.o
fs/cifs/smb2pdu.c: In function ‘SMB2_negotiate’:
fs/cifs/smb2pdu.c:822:16: warning: array subscript 1 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
822 | req->Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
| ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:823:16: warning: array subscript 2 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
823 | req->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
| ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:824:16: warning: array subscript 3 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
824 | req->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
| ~~~~~~~~~~~~~^~~
fs/cifs/smb2pdu.c:816:16: warning: array subscript 1 is above array bounds
of ‘__le16[1]’ {aka ‘short unsigned int[1]’} [-Warray-bounds]
816 | req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
| ~~~~~~~~~~~~~^~~
At the time, the size of array _Dialects_ was changed from 1 to 3 in struct
validate_negotiate_info_req, and then in 2019 it was changed from 3 to 4,
but those changes were never made in struct smb2_negotiate_req, which has
led to a 3 and a half years old out-of-bounds bug in function
SMB2_negotiate() (fs/cifs/smb2pdu.c).
Fix this by increasing the size of array _Dialects_ in struct
smb2_negotiate_req to 4.
Fixes: 9764c02fcbad ("SMB3: Add support for multidialect negotiate (SMB2.1 and later)") Fixes: d5c7076b772a ("smb3: add smb3.1.1 to default dialect list") Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Assuming
- //HOST/a is mounted on /mnt
- //HOST/b is mounted on /mnt/b
On a slow connection, running 'df' and killing it while it's
processing /mnt/b can make cifs_get_inode_info() returns -ERESTARTSYS.
This triggers the following chain of events:
=> the dentry revalidation fail
=> dentry is put and released
=> superblock associated with the dentry is put
=> /mnt/b is unmounted
This patch makes cifs_d_revalidate() return the error instead of 0
(invalid) when cifs_revalidate_dentry() fails, except for ENOENT (file
deleted) and ESTALE (file recreated).
Signed-off-by: Aurelien Aptel <aaptel@suse.com> Suggested-by: Shyam Prasad N <nspmangalore@gmail.com> Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com> CC: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xhci driver may in some special cases need to copy small amounts
of payload data to a bounce buffer in order to meet the boundary
and alignment restrictions set by the xHCI specification.
In the majority of these cases the data is in a sg list, and
driver incorrectly assumed data is always in urb->sg when using
the bounce buffer.
If data instead is contiguous, and in urb->transfer_buffer, we may still
need to bounce buffer a small part if data starts very close (less than
packet size) to a 64k boundary.
Check if sg list is used before copying data to/from it.
Fixes: f9c589e142d0 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer") Cc: stable@vger.kernel.org Reported-by: Andreas Hartmann <andihartmann@01019freenet.de> Tested-by: Andreas Hartmann <andihartmann@01019freenet.de> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210203113702.436762-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When MSI_FLAG_ACTIVATE_EARLY is set (which is the case for PCI),
__msi_domain_alloc_irqs() performs the activation of the interrupt (which
in the case of PCI results in the endpoint being programmed) as soon as the
interrupt is allocated.
But it appears that this is only done for the first vector, introducing an
inconsistent behaviour for PCI Multi-MSI.
Fix it by iterating over the number of vectors allocated to each MSI
descriptor. This is easily achieved by introducing a new
"for_each_msi_vector" iterator, together with a tiny bit of refactoring.
Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early") Reported-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210123122759.1781359-1-maz@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Our system encountered a re-init error when re-registering same kretprobe,
where the kretprobe_instance in rp->free_instances is illegally accessed
after re-init.
Implementation to avoid re-registration has been introduced for kprobe
before, but lags for register_kretprobe(). We must check if kprobe has
been re-registered before re-initializing kretprobe, otherwise it will
destroy the data struct of kretprobe registered, which can lead to memory
leak, system crash, also some unexpected behaviors.
We use check_kprobe_rereg() to check if kprobe has been re-registered
before running register_kretprobe()'s body, for giving a warning message
and terminate registration process.
Link: https://lkml.kernel.org/r/20210128124427.2031088-1-bobo.shaobowang@huawei.com Cc: stable@vger.kernel.org Fixes: 1f0ab40976460 ("kprobes: Prevent re-registration of the same kprobe")
[ The above commit should have been done for kretprobes too ] Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Ananth N Mavinakayanahalli <ananth@linux.ibm.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the driver uses .sta_add, station entries are only uploaded after the sta
is in assoc state. Fix early station rate table updates by deferring them
until the sta has been uploaded.
Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau <nbd@nbd.name> Link: https://lore.kernel.org/r/20210201083324.3134-1-nbd@nbd.name
[use rcu_access_pointer() instead since we won't dereference here] Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need to lock d_parent->d_lock before dget_dlock, or this may
have d_lockref updated parallelly like calltrace below which will
cause dentry->d_lockref leak and risk a crash.
CPU 0 CPU 1
ovl_set_redirect lookup_fast
ovl_get_redirect __d_lookup
dget_dlock
//no lock protection here spin_lock(&dentry->d_lock)
dentry->d_lockref.count++ dentry->d_lockref.count++
Commit fe8abf332b8f ("usb: dwc3: support clocks and resets for DWC3
core") introduced clock support and a new function named
dwc3_core_init_for_resume() which enables the clock before calling
dwc3_core_init() during resume as clocks get disabled during suspend.
Unfortunately in this commit the DWC3_GCTL_PRTCAP_OTG case was forgotten
and therefore during resume, a platform could call dwc3_core_init()
without re-enabling the clocks first, preventing to resume properly.
So update the resume path to call dwc3_core_init_for_resume() as it
should.
dwc2_hsotg_process_req_status uses ep_from_windex() to retrieve
the endpoint for the index provided in the wIndex request param.
In a test-case with a rndis gadget running and sending a malformed
packet to it like:
dev.ctrl_transfer(
0x82, # bmRequestType
0x00, # bRequest
0x0000, # wValue
0x0001, # wIndex
0x00 # wLength
)
it is possible to cause a crash:
This happens because ep_from_windex wants to compare the endpoint
direction even if index_to_ep() didn't return an endpoint due to
the direction not matching.
The fix is easy insofar that the actual direction check is already
happening when calling index_to_ep() which will return NULL if there
is no endpoint for the targeted direction, so the offending check
can go away completely.
Some devices, such as the Winbond Electronics Corp. Virtual Com Port
(Vendor=0416, ProdId=5011), lockup when usb_set_interface() or
usb_clear_halt() are called. This device has only a single
altsetting, so it should not be necessary to call usb_set_interface().
Acked-by: Pete Zaitcev <zaitcev@redhat.com> Signed-off-by: Jeremy Figgins <kernel@jeremyfiggins.com> Link: https://lore.kernel.org/r/YAy9kJhM/rG8EQXC@watson Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With kaslr the kernel image is placed at a random place, so starting the
bottom-up allocation with the kernel_end can result in an allocation
failure and a warning like this one:
At the same time, the kernel image is protected with memblock_reserve(),
so we can just start searching at PAGE_SIZE. In this case the bottom-up
allocation has the same chances to success as a top-down allocation, so
there is no reason to fallback in the case of a failure. All together it
simplifies the logic.
Link: https://lkml.kernel.org/r/20201217201214.3414100-2-guro@fb.com Fixes: 8fabc623238e ("powerpc: Ensure that swiotlb buffer is allocated from low memory") Signed-off-by: Roman Gushchin <guro@fb.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Rik van Riel <riel@surriel.com> Cc: Wonhyuk Yang <vvghjk1234@gmail.com> Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com> 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>
When sending a packet, we will prepend it with an LAPB header.
This modifies the shared parts of a cloned skb, so we should copy the
skb rather than just clone it, before we prepend the header.
In "Documentation/networking/driver.rst" (the 2nd point), it states
that drivers shouldn't modify the shared parts of a cloned skb when
transmitting.
The "dev_queue_xmit_nit" function in "net/core/dev.c", which is called
when an skb is being sent, clones the skb and sents the clone to
AF_PACKET sockets. Because the LAPB drivers first remove a 1-byte
pseudo-header before handing over the skb to us, if we don't copy the
skb before prepending the LAPB header, the first byte of the packets
received on AF_PACKET sockets can be corrupted.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He <xie.he.0141@gmail.com> Acked-by: Martin Schiller <ms@dev.tdt.de> Link: https://lore.kernel.org/r/20210201055706.415842-1-xie.he.0141@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Dcfg was overlapping with clockgen address space which resulted
in failure in memory allocation for dcfg. According regs description
dcfg size should not be bigger than 4KB.
AF_RXRPC sockets use UDP ports in encap mode. This causes socket and dst
from an incoming packet to get stolen and attached to the UDP socket from
whence it is leaked when that socket is closed.
When a network namespace is removed, the wait for dst records to be cleaned
up happens before the cleanup of the rxrpc and UDP socket, meaning that the
wait never finishes.
Fix this by moving the rxrpc (and, by dependence, the afs) private
per-network namespace registrations to the device group rather than subsys
group. This allows cached rxrpc local endpoints to be cleared and their
UDP sockets closed before we try waiting for the dst records.
The symptom is that lines looking like the following:
unregister_netdevice: waiting for lo to become free
get emitted at regular intervals after running something like the
referenced syzbot test.
Thanks to Vadim for tracking this down and work out the fix.
Reported-by: syzbot+df400f2f24a1677cd7e0@syzkaller.appspotmail.com Reported-by: Vadim Fedorenko <vfedorenko@novek.ru> Fixes: 5271953cad31 ("rxrpc: Use the UDP encap_rcv hook") Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Vadim Fedorenko <vfedorenko@novek.ru> Link: https://lore.kernel.org/r/161196443016.3868642.5577440140646403533.stgit@warthog.procyon.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
kernel/elfcore.c only contains weak symbols, which triggers a bug with
clang in combination with recordmcount:
Cannot find symbol for section 2: .text.
kernel/elfcore.o: failed
Move the empty stubs into linux/elfcore.h as inline functions. As only
two architectures use these, just use the architecture specific Kconfig
symbols to key off the declaration.
create_worker() will already set the right affinity using
kthread_bind_mask(), this means only the rescuer will need to change
it's affinity.
Howveer, while in cpu-hot-unplug a regular task is not allowed to run
on online&&!active as it would be pushed away quite agressively. We
need KTHREAD_IS_PER_CPU to survive in that environment.
Therefore set the affinity after getting that magic flag.
There is a need to distinguish geniune per-cpu kthreads from kthreads
that happen to have a single CPU affinity.
Geniune per-cpu kthreads are kthreads that are CPU affine for
correctness, these will obviously have PF_KTHREAD set, but must also
have PF_NO_SETAFFINITY set, lest userspace modify their affinity and
ruins things.
However, these two things are not sufficient, PF_NO_SETAFFINITY is
also set on other tasks that have their affinities controlled through
other means, like for instance workqueues.
Therefore another bit is needed; it turns out kthread_create_per_cpu()
already has such a bit: KTHREAD_IS_PER_CPU, which is used to make
kthread_park()/kthread_unpark() work correctly.
Expose this flag and remove the implicit setting of it from
kthread_create_on_cpu(); the io_uring usage of it seems dubious at
best.
Thanks to a recent binutils change which doesn't generate unused
symbols, it's now possible for thunk_64.o be completely empty without
CONFIG_PREEMPTION: no text, no data, no symbols.
We could edit the Makefile to only build that file when
CONFIG_PREEMPTION is enabled, but that will likely create confusion
if/when the thunks end up getting used by some other code again.
These tests do pass on little endian machines, as the kernel will
still emulate those instructions even when running little
endian (which is arguably a kernel bug).
But we don't really need to test that case, so ifdef those
instructions out to get the alignment test building again.
While testing live partition mobility, we have observed occasional crashes
of the Linux partition. What we've seen is that during the live migration,
for specific configurations with large amounts of memory, slow network
links, and workloads that are changing memory a lot, the partition can end
up being suspended for 30 seconds or longer. This resulted in the following
scenario:
CPU 0 CPU 1
------------------------------- ----------------------------------
scsi_queue_rq migration_store
-> blk_mq_start_request -> rtas_ibm_suspend_me
-> blk_add_timer -> on_each_cpu(rtas_percpu_suspend_me
_______________________________________V
|
V
-> IPI from CPU 1
-> rtas_percpu_suspend_me
-> __rtas_suspend_last_cpu
Normally, the SCMD_STATE_COMPLETE bit would protect against the command
completion and the timeout, but that doesn't work here, since we don't
check that at all in the SCSI_MLQUEUE_HOST_BUSY path.
In this case we end up calling scsi_queue_insert on a request that has
already been queued, or possibly even freed, and we crash.
The patch below simply increases the default I/O timeout to avoid this race
condition. This is also the timeout value that nearly all IBM SAN storage
recommends setting as the default value.
A race condition exists between the response handler getting called because
of exchange_mgr_reset() (which clears out all the active XIDs) and the
response we get via an interrupt.
Sequence of events:
rport ba0200: Port timeout, state PLOGI
rport ba0200: Port entered PLOGI state from PLOGI state
xid 1052: Exchange timer armed : 20000 msecs xid timer armed here
rport ba0200: Received LOGO request while in state PLOGI
rport ba0200: Delete port
rport ba0200: work event 3
rport ba0200: lld callback ev 3
bnx2fc: rport_event_hdlr: event = 3, port_id = 0xba0200
bnx2fc: ba0200 - rport not created Yet!!
/* Here we reset any outstanding exchanges before
freeing rport using the exch_mgr_reset() */
xid 1052: Exchange timer canceled
/* Here we got two responses for one xid */
xid 1052: invoking resp(), esb 20000000 state 3
xid 1052: invoking resp(), esb 20000000 state 3
xid 1052: fc_rport_plogi_resp() : ep->resp_active 2
xid 1052: fc_rport_plogi_resp() : ep->resp_active 2
Skip the response if the exchange is already completed.
If the port is in SRP_RPORT_FAIL_FAST state when srp_reconnect_rport() is
entered, a transition to SDEV_BLOCK would be illegal, and a kernel WARNING
would be triggered. Skip scsi_target_block() in this case.
Link: https://lore.kernel.org/r/20210111142541.21534-1-mwilck@suse.com Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin Wilck <mwilck@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The Estar Beauty HD (MID 7316R) tablet uses a Goodix touchscreen,
with the X and Y coordinates swapped compared to the LCD panel.
Add a touchscreen_dmi entry for this adding a "touchscreen-swapped-x-y"
device-property to the i2c-client instantiated for this device before
the driver binds.
This is the first entry of a Goodix touchscreen to touchscreen_dmi.c,
so far DMI quirks for Goodix touchscreen's have been added directly
to drivers/input/touchscreen/goodix.c. Currently there are 3
DMI tables in goodix.c:
1. rotated_screen[] for devices where the touchscreen is rotated
180 degrees vs the LCD panel
2. inverted_x_screen[] for devices where the X axis is inverted
3. nine_bytes_report[] for devices which use a non standard touch
report size
Arguably only 3. really needs to be inside the driver and the other
2 cases are better handled through the generic touchscreen DMI quirk
mechanism from touchscreen_dmi.c, which allows adding device-props to
any i2c-client. Esp. now that goodix.c is using the generic
touchscreen_properties code.
Alternative to the approach from this patch we could add a 4th
dmi_system_id table for devices with swapped-x-y axis to goodix.c,
but that seems undesirable.
On deferred probe, we will get the following splat:
cpcap-usb-phy cpcap-usb-phy.0: could not initialize VBUS or ID IIO: -517
WARNING: CPU: 0 PID: 21 at drivers/regulator/core.c:2123 regulator_put+0x68/0x78
...
(regulator_put) from [<c068ebf0>] (release_nodes+0x1b4/0x1fc)
(release_nodes) from [<c068a9a4>] (really_probe+0x104/0x4a0)
(really_probe) from [<c068b034>] (driver_probe_device+0x58/0xb4)
proc_get_long() is a funny function. It uses simple_strtoul() and for a
good reason. proc_get_long() wants to always succeed the parse and
return the maybe incorrect value and the trailing characters to check
against a pre-defined list of acceptable trailing values. However,
simple_strtoul() explicitly ignores overflows which can cause funny
things like the following to happen:
(Which will cause your system to silently die behind your back.)
On the other hand kstrtoul() does do overflow detection but does not
return the trailing characters, and also fails the parse when anything
other than '\n' is a trailing character whereas proc_get_long() wants to
be more lenient.
Now, before adding another kstrtoul() function let's simply add a static
parse strtoul_lenient() which:
- fails on overflow with -ERANGE
- returns the trailing characters to the caller
The reason why we should fail on ERANGE is that we already do a partial
fail on overflow right now. Namely, when the TMPBUFLEN is exceeded. So
we already reject values such as 184467440737095516160 (21 chars) but
accept values such as 18446744073709551616 (20 chars) but both are
overflows. So we should just always reject 64bit overflows and not
special-case this based on the number of chars.
Link: http://lkml.kernel.org/r/20190107222700.15954-2-christian@brauner.io Signed-off-by: Christian Brauner <christian@brauner.io> Acked-by: Kees Cook <keescook@chromium.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Waiman Long <longman@redhat.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Joerg Vehlow <lkml@jv-coder.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Calling acpi_thermal_check() from acpi_thermal_notify() directly
is problematic if _TMP triggers Notify () on the thermal zone for
which it has been evaluated (which happens on some systems), because
it causes a new acpi_thermal_notify() invocation to be queued up
every time and if that takes place too often, an indefinite number of
pending work items may accumulate in kacpi_notify_wq over time.
Besides, it is not really useful to queue up a new invocation of
acpi_thermal_check() if one of them is pending already.
For these reasons, rework acpi_thermal_notify() to queue up a thermal
check instead of calling acpi_thermal_check() directly and only allow
one thermal check to be pending at a time. Moreover, only allow one
acpi_thermal_check_fn() instance at a time to run
thermal_zone_device_update() for one thermal zone and make it return
early if it sees other instances running for the same thermal zone.
While at it, fold acpi_thermal_check() into acpi_thermal_check_fn(),
as it is only called from there after the other changes made here.
[This issue appears to have been exposed by commit 6d25be5782e4
("sched/core, workqueues: Distangle worker accounting from rq
lock"), but it is unclear why it was not visible earlier.]
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=208877 Reported-by: Stephen Berman <stephen.berman@gmx.net> Diagnosed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Stephen Berman <stephen.berman@gmx.net> Cc: All applicable <stable@vger.kernel.org>
[bigeasy: Backported to v5.4.y] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ensure that received Command-Response Queue (CRQ) entries are
properly read in order by the driver. dma_rmb barrier has
been added before accessing the CRQ descriptor to ensure
the entire descriptor is read before processing.
Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol") Signed-off-by: Lijun Pan <ljp@linux.ibm.com> Link: https://lore.kernel.org/r/20210128013442.88319-1-ljp@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Upon receiving a cumulative ACK that changes the congestion state from
Disorder to Open, the TLP timer is not set. If the sender is app-limited,
it can only wait for the RTO timer to expire and retransmit.
The reason for this is that the TLP timer is set before the congestion
state changes in tcp_ack(), so we delay the time point of calling
tcp_set_xmit_timer() until after tcp_fastretrans_alert() returns and
remove the FLAG_SET_XMIT_TIMER from ack_flag when the RACK reorder timer
is set.
This commit has two additional benefits:
1) Make sure to reset RTO according to RFC6298 when receiving ACK, to
avoid spurious RTO caused by RTO timer early expires.
2) Reduce the xmit timer reschedule once per ACK when the RACK reorder
timer is set.
Function __team_compute_features() is protected by team->lock
mutex when it is called from team_compute_features() used when
features of an underlying device is changed. This causes
a deadlock when NETDEV_FEAT_CHANGE notifier for underlying device
is fired due to change propagated from team driver (e.g. MTU
change). It's because callbacks like team_change_mtu() or
team_vlan_rx_{add,del}_vid() protect their port list traversal
by team->lock mutex.
Example (r8169 case where this driver disables TSO for certain MTU
values):
...
[ 6391.348202] __mutex_lock.isra.6+0x2d0/0x4a0
[ 6391.358602] team_device_event+0x9d/0x160 [team]
[ 6391.363756] notifier_call_chain+0x47/0x70
[ 6391.368329] netdev_update_features+0x56/0x60
[ 6391.373207] rtl8169_change_mtu+0x14/0x50 [r8169]
[ 6391.378457] dev_set_mtu_ext+0xe1/0x1d0
[ 6391.387022] dev_set_mtu+0x52/0x90
[ 6391.390820] team_change_mtu+0x64/0xf0 [team]
[ 6391.395683] dev_set_mtu_ext+0xe1/0x1d0
[ 6391.399963] do_setlink+0x231/0xf50
...
In fact team_compute_features() called from team_device_event()
does not need to be protected by team->lock mutex and rcu_read_lock()
is sufficient there for port list traversal.
Put the device to avoid resource leak on path that the polling flag is
invalid.
Fixes: a831b9132065 ("NFC: Do not return EBUSY when stopping a poll that's already stopped") Signed-off-by: Pan Bian <bianpan2016@163.com> Link: https://lore.kernel.org/r/20210121153745.122184-1-bianpan2016@163.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Goto to the label put_dev instead of the label error to fix potential
resource leak on path that the target index is invalid.
Fixes: c4fbb6515a4d ("NFC: The core part should generate the target index") Signed-off-by: Pan Bian <bianpan2016@163.com> Link: https://lore.kernel.org/r/20210121152748.98409-1-bianpan2016@163.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 9ebeddef58c4 ("rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record")
Then release ref in __rxrpc_put_peer and rxrpc_put_peer_locked.
Fixes: 9ebeddef58c4 ("rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record") Signed-off-by: Takeshi Misawa <jeliantsurux@gmail.com> Reported-and-tested-by: syzbot+305326672fed51b205f7@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/161183091692.3506637.3206605651502458810.stgit@warthog.procyon.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit c40aaaac1018 ("iommu/vt-d: Gracefully handle DMAR units
with no supported address widths") dmar.c needs struct iommu_device to
be selected. We can drop this dependency by not dereferencing struct
iommu_device if IOMMU_API is not selected and by reusing the information
stored in iommu->drhd->ignored instead.
This fixes the following build error when IOMMU_API is not selected:
drivers/iommu/dmar.c: In function ‘free_iommu’:
drivers/iommu/dmar.c:1139:41: error: ‘struct iommu_device’ has no member named ‘ops’
1139 | if (intel_iommu_enabled && iommu->iommu.ops) {
^
Fixes: c40aaaac1018 ("iommu/vt-d: Gracefully handle DMAR units with no supported address widths") Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Acked-by: Lu Baolu <baolu.lu@linux.intel.com> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20201013073055.11262-1-brgl@bgdev.pl Signed-off-by: Joerg Roedel <jroedel@suse.de>
[ - context change due to moving drivers/iommu/dmar.c to
drivers/iommu/intel/dmar.c
- set the drhr in the iommu like in upstream commit b1012ca8dc4f
("iommu/vt-d: Skip TE disabling on quirky gfx dedicated iommu") ] Signed-off-by: Filippo Sironi <sironi@amazon.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "bec" struct isn't necessarily always initialized. For example, the
mcp251xfd_get_berr_counter() function doesn't initialize anything if the
interface is down.
Fixes: 52c793f24054 ("can: netlink support for bus-error reporting and counters") Link: https://lore.kernel.org/r/YAkaRdRJncsJO8Ve@mwanda Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
syzbot reported a crash that happened when changing the interface
type around a lot, and while it might have been easy to fix just
the symptom there, a little deeper investigation found that really
the reason is that we allowed packets to be transmitted while in
the middle of changing the interface type.
Disallow TX by stopping the queues while changing the type.
If we spin for a long time in memory reads that (for some reason in
hardware) take a long time, then we'll eventually get messages such
as
watchdog: BUG: soft lockup - CPU#2 stuck for 24s! [kworker/2:2:272]
This is because the reading really does take a very long time, and
we don't schedule, so we're hogging the CPU with this task, at least
if CONFIG_PREEMPT is not set, e.g. with CONFIG_PREEMPT_VOLUNTARY=y.
Previously I misinterpreted the situation and thought that this was
only going to happen if we had interrupts disabled, and then fixed
this (which is good anyway, however), but that didn't always help;
looking at it again now I realized that the spin unlock will only
reschedule if CONFIG_PREEMPT is used.
In order to avoid this issue, change the code to cond_resched() if
we've been spinning for too long here.
There's no reason to use ktime_get() since we don't need any better
precision than jiffies, and since we no longer disable interrupts
around this code (when grabbing NIC access), jiffies will work fine.
Use jiffies instead of ktime_get().
This cleanup is preparation for the following patch "iwlwifi: pcie: reschedule
in long-running memory reads". The code gets simpler with the weird clock use
etc. removed before we add cond_resched().
If the server returns a new stateid that does not match the one in our
cache, then pnfs_layout_process() will leak the layout segments returned
by pnfs_mark_layout_stateid_invalid().
Fixes: 9888d837f3cf ("pNFS: Force a retry of LAYOUTGET if the stateid doesn't match our cache") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The max_recv_sge value is wrongly reported when calling query_qp, This is
happening due to a typo when assigning the max_recv_sge value, the value
of sq_max_sges was assigned instead of rq_max_sges.
Fixes: 3e5c02c9ef9a ("iw_cxgb4: Support query_qp() verb") Link: https://lore.kernel.org/r/20210114191423.423529-1-kamalheib1@gmail.com Signed-off-by: Kamal Heib <kamalheib1@gmail.com> Reviewed-by: Potnuri Bharat Teja <bharat@chelsio.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
projects / linux-stable / log