tcf_action_init_1() loads tc action modules automatically with
request_module() after parsing the tc action names, and it drops RTNL
lock and re-holds it before and after request_module(). This causes a
lot of troubles, as discovered by syzbot, because we can be in the
middle of batch initializations when we create an array of tc actions.
One of the problem is deadlock:
CPU 0 CPU 1
rtnl_lock();
for (...) {
tcf_action_init_1();
-> rtnl_unlock();
-> request_module();
rtnl_lock();
for (...) {
tcf_action_init_1();
-> tcf_idr_check_alloc();
// Insert one action into idr,
// but it is not committed until
// tcf_idr_insert_many(), then drop
// the RTNL lock in the _next_
// iteration
-> rtnl_unlock();
-> rtnl_lock();
-> a_o->init();
-> tcf_idr_check_alloc();
// Now waiting for the same index
// to be committed
-> request_module();
-> rtnl_lock()
// Now waiting for RTNL lock
}
rtnl_unlock();
}
rtnl_unlock();
This is not easy to solve, we can move the request_module() before
this loop and pre-load all the modules we need for this netlink
message and then do the rest initializations. So the loop breaks down
to two now:
for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
struct tc_action_ops *a_o;
for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
act = tcf_action_init_1(ops[i - 1]...);
}
Although this looks serious, it only has been reported by syzbot, so it
seems hard to trigger this by humans. And given the size of this patch,
I'd suggest to make it to net-next and not to backport to stable.
This patch has been tested by syzbot and tested with tdc.py by me.
When police action is created by cls API tcf_exts_validate() first
conditional that calls tcf_action_init_1() directly, the action idr is not
updated according to latest changes in action API that require caller to
commit newly created action to idr with tcf_idr_insert_many(). This results
such action not being accessible through act API and causes crash reported
by syzbot:
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: null-ptr-deref in atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
BUG: KASAN: null-ptr-deref in __tcf_idr_release net/sched/act_api.c:178 [inline]
BUG: KASAN: null-ptr-deref in tcf_idrinfo_destroy+0x129/0x1d0 net/sched/act_api.c:598
Read of size 4 at addr 0000000000000010 by task kworker/u4:5/204
Having two ring buffers per-peer means that every peer results in two
massive ring allocations. On an 8-core x86_64 machine, this commit
reduces the per-peer allocation from 18,688 bytes to 1,856 bytes, which
is an 90% reduction. Ninety percent! With some single-machine
deployments approaching 500,000 peers, we're talking about a reduction
from 7 gigs of memory down to 700 megs of memory.
In order to get rid of these per-peer allocations, this commit switches
to using a list-based queueing approach. Currently GSO fragments are
chained together using the skb->next pointer (the skb_list_* singly
linked list approach), so we form the per-peer queue around the unused
skb->prev pointer (which sort of makes sense because the links are
pointing backwards). Use of skb_queue_* is not possible here, because
that is based on doubly linked lists and spinlocks. Multiple cores can
write into the queue at any given time, because its writes occur in the
start_xmit path or in the udp_recv path. But reads happen in a single
workqueue item per-peer, amounting to a multi-producer, single-consumer
paradigm.
The MPSC queue is implemented locklessly and never blocks. However, it
is not linearizable (though it is serializable), with a very tight and
unlikely race on writes, which, when hit (some tiny fraction of the
0.15% of partial adds on a fully loaded 16-core x86_64 system), causes
the queue reader to terminate early. However, because every packet sent
queues up the same workqueue item after it is fully added, the worker
resumes again, and stopping early isn't actually a problem, since at
that point the packet wouldn't have yet been added to the encryption
queue. These properties allow us to avoid disabling interrupts or
spinning. The design is based on Dmitry Vyukov's algorithm [1].
Performance-wise, ordinarily list-based queues aren't preferable to
ringbuffers, because of cache misses when following pointers around.
However, we *already* have to follow the adjacent pointers when working
through fragments, so there shouldn't actually be any change there. A
potential downside is that dequeueing is a bit more complicated, but the
ptr_ring structure used prior had a spinlock when dequeueing, so all and
all the difference appears to be a wash.
Actually, from profiling, the biggest performance hit, by far, of this
commit winds up being atomic_add_unless(count, 1, max) and atomic_
dec(count), which account for the majority of CPU time, according to
perf. In that sense, the previous ring buffer was superior in that it
could check if it was full by head==tail, which the list-based approach
cannot do.
But all and all, this enables us to get massive memory savings, allowing
WireGuard to scale for real world deployments, without taking much of a
performance hit.
In order to test ndo_start_xmit being called in parallel, explicitly add
separate tests, which should all run on different cores. This should
help tease out bugs associated with queueing up packets from different
cores in parallel. Currently, it hasn't found those types of bugs, but
given future planned work, this is a useful regression to avoid.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The icmp{,v6}_send functions make all sorts of use of skb->cb, casting
it with IPCB or IP6CB, assuming the skb to have come directly from the
inet layer. But when the packet comes from the ndo layer, especially
when forwarded, there's no telling what might be in skb->cb at that
point. As a result, the icmp sending code risks reading bogus memory
contents, which can result in nasty stack overflows such as this one
reported by a user:
In icmp_send, skb->cb is cast with IPCB and an ip_options struct is read
from it. The optlen parameter there is of particular note, as it can
induce writes beyond bounds. There are quite a few ways that can happen
in __ip_options_echo. For example:
// sptr/skb are attacker-controlled skb bytes
sptr = skb_network_header(skb);
// dptr/dopt points to stack memory allocated by __icmp_send
dptr = dopt->__data;
// sopt is the corrupt skb->cb in question
if (sopt->rr) {
optlen = sptr[sopt->rr+1]; // corrupt skb->cb + skb->data
soffset = sptr[sopt->rr+2]; // corrupt skb->cb + skb->data
// this now writes potentially attacker-controlled data, over
// flowing the stack:
memcpy(dptr, sptr+sopt->rr, optlen);
}
In the icmpv6_send case, the story is similar, but not as dire, as only
IP6CB(skb)->iif and IP6CB(skb)->dsthao are used. The dsthao case is
worse than the iif case, but it is passed to ipv6_find_tlv, which does
a bit of bounds checking on the value.
This is easy to simulate by doing a `memset(skb->cb, 0x41,
sizeof(skb->cb));` before calling icmp{,v6}_ndo_send, and it's only by
good fortune and the rarity of icmp sending from that context that we've
avoided reports like this until now. For example, in KASAN:
BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0xa0e/0x12b0
Write of size 38 at addr ffff888006f1f80e by task ping/89
CPU: 2 PID: 89 Comm: ping Not tainted 5.10.0-rc7-debug+ #5
Call Trace:
dump_stack+0x9a/0xcc
print_address_description.constprop.0+0x1a/0x160
__kasan_report.cold+0x20/0x38
kasan_report+0x32/0x40
check_memory_region+0x145/0x1a0
memcpy+0x39/0x60
__ip_options_echo+0xa0e/0x12b0
__icmp_send+0x744/0x1700
Actually, out of the 4 drivers that do this, only gtp zeroed the cb for
the v4 case, while the rest did not. So this commit actually removes the
gtp-specific zeroing, while putting the code where it belongs in the
shared infrastructure of icmp{,v6}_ndo_send.
This commit fixes the issue by passing an empty IPCB or IP6CB along to
the functions that actually do the work. For the icmp_send, this was
already trivial, thanks to __icmp_send providing the plumbing function.
For icmpv6_send, this required a tiny bit of refactoring to make it
behave like the v4 case, after which it was straight forward.
Currently breakpoints in kernel .init.text section are not handled
correctly while allowing to remove them even after corresponding pages
have been freed.
Fix it via killing .init.text section breakpoints just prior to initmem
pages being freed.
Doug: "HW breakpoints aren't handled by this patch but it's probably
not such a big deal".
Link: https://lkml.kernel.org/r/20210224081652.587785-1-sumit.garg@linaro.org Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Suggested-by: Doug Anderson <dianders@chromium.org> Acked-by: Doug Anderson <dianders@chromium.org> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Tested-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Peter Zijlstra <peterz@infradead.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 BXT/GLK DPLL can't generate certain frequencies. We already
reject the 233-240MHz range on both. But on GLK the DPLL max
frequency was bumped from 300MHz to 594MHz, so now we get to
also worry about the 446-480MHz range (double the original
problem range). Reject any frequency within the higher
problematic range as well.
Metadata resize shouldn't happen in the ctr. The ctr loads a temporary
(inactive) table that will only become active upon resume. That is why
resize should always be done in terms of resume. Otherwise a load (ctr)
whose inactive table never becomes active will incorrectly resize the
metadata.
Also, perform the resize directly in preresume, instead of using the
worker to do it.
The worker might run other metadata operations, e.g., it could start
digestion, before resizing the metadata. These operations will end up
using the old size.
In case of devices with at most 64 blocks, the digestion of consecutive
eras uses the writeset of the first era as the writeset of all eras to
digest, leading to lost writes. That is, we lose the information about
what blocks were written during the affected eras.
The digestion code uses a dm_disk_bitset object to access the archived
writesets. This structure includes a one word (64-bit) cache to reduce
the number of array lookups.
This structure is initialized only once, in metadata_digest_start(),
when we kick off digestion.
But, when we insert a new writeset into the writeset tree, before the
digestion of the previous writeset is done, or equivalently when there
are multiple writesets in the writeset tree to digest, then all these
writesets are digested using the same cache and the cache is not
re-initialized when moving from one writeset to the next.
For devices with more than 64 blocks, i.e., the size of the cache, the
cache is indirectly invalidated when we move to a next set of blocks, so
we avoid the bug.
But for devices with at most 64 blocks we end up using the same cached
data for digesting all archived writesets, i.e., the cache is loaded
when digesting the first writeset and it never gets reloaded, until the
digestion is done.
As a result, the writeset of the first era to digest is used as the
writeset of all the following archived eras, leading to lost writes.
Fix this by reinitializing the dm_disk_bitset structure, and thus
invalidating the cache, every time the digestion code starts digesting a
new writeset.
dm-era doesn't support changing the data block size of existing devices,
so check explicitly that the requested block size for a new target
matches the one stored in the metadata.
In case of a system crash, dm-era might fail to mark blocks as written
in its metadata, although the corresponding writes to these blocks were
passed down to the origin device and completed successfully.
Consider the following sequence of events:
1. We write to a block that has not been yet written in the current era
2. era_map() checks the in-core bitmap for the current era and sees
that the block is not marked as written.
3. The write is deferred for submission after the metadata have been
updated and committed.
4. The worker thread processes the deferred write
(process_deferred_bios()) and marks the block as written in the
in-core bitmap, **before** committing the metadata.
5. The worker thread starts committing the metadata.
6. We do more writes that map to the same block as the write of step (1)
7. era_map() checks the in-core bitmap and sees that the block is marked
as written, **although the metadata have not been committed yet**.
8. These writes are passed down to the origin device immediately and the
device reports them as completed.
9. The system crashes, e.g., power failure, before the commit from step
(5) finishes.
When the system recovers and we query the dm-era target for the list of
written blocks it doesn't report the aforementioned block as written,
although the writes of step (6) completed successfully.
The issue is that era_map() decides whether to defer or not a write
based on non committed information. The root cause of the bug is that we
update the in-core bitmap, **before** committing the metadata.
Fix this by updating the in-core bitmap **after** successfully
committing the metadata.
Following a system crash, dm-era fails to recover the committed writeset
for the current era, leading to lost writes. That is, we lose the
information about what blocks were written during the affected era.
dm-era assumes that the writeset of the current era is archived when the
device is suspended. So, when resuming the device, it just moves on to
the next era, ignoring the committed writeset.
This assumption holds when the device is properly shut down. But, when
the system crashes, the code that suspends the target never runs, so the
writeset for the current era is not archived.
There are three issues that cause the committed writeset to get lost:
1. dm-era doesn't load the committed writeset when opening the metadata
2. The code that resizes the metadata wipes the information about the
committed writeset (assuming it was loaded at step 1)
3. era_preresume() starts a new era, without taking into account that
the current era might not have been archived, due to a system crash.
To fix this:
1. Load the committed writeset when opening the metadata
2. Fix the code that resizes the metadata to make sure it doesn't wipe
the loaded writeset
3. Fix era_preresume() to check for a loaded writeset and archive it,
before starting a new era.
LVM doesn't like it when the target returns different values from what
was set in the constructor. Fix dm-writecache so that the returned
table values are exactly the same as requested values.
Fix dm_table_supports_zoned_model() and invert logic of both
iterate_devices_callout_fn so that all devices' zoned capabilities are
properly checked.
Add one more parameter to dm_table_any_dev_attr(), which is actually
used as the @data parameter of iterate_devices_callout_fn, so that
dm_table_matches_zone_sectors() can be replaced by
dm_table_any_dev_attr().
According to the definition of dm_iterate_devices_fn:
* This function must iterate through each section of device used by the
* target until it encounters a non-zero return code, which it then returns.
* Returns zero if no callout returned non-zero.
For some target type (e.g. dm-stripe), one call of iterate_devices() may
iterate multiple underlying devices internally, in which case a non-zero
return code returned by iterate_devices_callout_fn will stop the iteration
in advance. No iterate_devices_callout_fn should return non-zero unless
device iteration should stop.
Rename dm_table_requires_stable_pages() to dm_table_any_dev_attr() and
elevate it for reuse to stop iterating (and return non-zero) on the
first device that causes iterate_devices_callout_fn to return non-zero.
Use dm_table_any_dev_attr() to properly iterate through devices.
Rename device_is_nonrot() to device_is_rotational() and invert logic
accordingly to fix improper disposition.
Fixes: c3c4555edd10 ("dm table: clear add_random unless all devices have it set") Fixes: 4693c9668fdc ("dm table: propagate non rotational flag") Cc: stable@vger.kernel.org Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The system would deadlock when swapping to a dm-crypt device. The reason
is that for each incoming write bio, dm-crypt allocates memory that holds
encrypted data. These excessive allocations exhaust all the memory and the
result is either deadlock or OOM trigger.
This patch limits the number of in-flight swap bios, so that the memory
consumed by dm-crypt is limited. The limit is enforced if the target set
the "limit_swap_bios" variable and if the bio has REQ_SWAP set.
Non-swap bios are not affected becuase taking the semaphore would cause
performance degradation.
This is similar to request-based drivers - they will also block when the
number of requests is over the limit.
When starting an iomap write, gfs2_quota_lock_check -> gfs2_quota_lock
-> gfs2_quota_hold is called from gfs2_iomap_begin. At the end of the
write, before unlocking the quotas, punch_hole -> gfs2_quota_hold can be
called again in gfs2_iomap_end, which is incorrect and leads to a failed
assertion. Instead, move the call to gfs2_quota_unlock before the call
to punch_hole to fix that.
Patch fb6791d100d1 was designed to allow gfs2 to unmount quicker by
skipping the step where it tells dlm to unlock glocks in EX with lvbs.
This was done because when gfs2 unmounts a file system, it destroys the
dlm lockspace shortly after it destroys the glocks so it doesn't need to
unlock them all: the unlock is implied when the lockspace is destroyed
by dlm.
However, that patch introduced a use-after-free in dlm: as part of its
normal dlm_recoverd process, it can call ls_recovery to recover dead
locks. In so doing, it can call recover_rsbs which calls recover_lvb for
any mastered rsbs. Func recover_lvb runs through the list of lkbs queued
to the given rsb (if the glock is cached but unlocked, it will still be
queued to the lkb, but in NL--Unlocked--mode) and if it has an lvb,
copies it to the rsb, thus trying to preserve the lkb. However, when
gfs2 skips the dlm unlock step, it frees the glock and its lvb, which
means dlm's function recover_lvb references the now freed lvb pointer,
copying the freed lvb memory to the rsb.
This patch changes the check in gdlm_put_lock so that it calls
dlm_unlock for all glocks that contain an lvb pointer.
Fixes: fb6791d100d1 ("GFS2: skip dlm_unlock calls in unmount") Cc: stable@vger.kernel.org # v3.8+ Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If go_free is defined, function signal_our_withdraw is supposed to
synchronize on the GLF_FREEING flag of the inode glock, but it
accidentally does that on the live glock. Fix that and disambiguate
the glock variables.
Fixes: 601ef0d52e96 ("gfs2: Force withdraw to replay journals and wait for it to finish") Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 7a2da5d7960a ("spi: fsl: Fix driver breakage when SPI_CS_HIGH
is not set in spi->mode") broke our MPC8309 board by effectively
inverting the boolean value passed to fsl_spi_cs_control. The
SPISEL_BOOT signal is used as chipselect, but it's not a gpio, so
we cannot rely on gpiolib handling the polarity.
Adapt to the new world order by inverting the logic here. This does
assume that the slave sitting at the SPISEL_BOOT is active low, but
should that ever turn out not to be the case, one can create a stub
gpiochip driver controlling a single gpio (or rather, a single "spo",
special-purpose output).
Fixes: 7a2da5d7960a ("spi: fsl: Fix driver breakage when SPI_CS_HIGH is not set in spi->mode") Cc: stable@vger.kernel.org Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Link: https://lore.kernel.org/r/20210130143545.505613-1-rasmus.villemoes@prevas.dk Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Back in 2.1.29 the clear_user() guts (__bzero()) had been merged
with memset(). Unfortunately, while all exception handlers had been
copied, one of the exception table entries got lost. As the result,
clear_user() starting at 128*n bytes before the end of page and
spanning between 8 and 127 bytes into the next page would oops when
the second page is unmapped. It's trivial to reproduce - all
it takes is
which had been oopsing since March 1997. Says something about
the quality of test coverage... ;-/ And while today sparc32 port
is nearly dead, back in '97 it had been very much alive; in fact,
sparc64 had only been in mainline for 3 months by that point...
Cc: stable@kernel.org Fixes: v2.1.29 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Passwords can contain ',' which are also used as the separator between
mount options. Mount.cifs will escape all ',' characters as the string ",,".
Update parsing of the mount options to detect ",," and treat it as a single
'c' character.
Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api") Cc: stable@vger.kernel.org # 5.11 Reported-by: Simon Taylor <simon@simon-taylor.me.uk> Tested-by: Simon Taylor <simon@simon-taylor.me.uk> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some servers seem to mistakenly report different values for
capabilities and share flags, so we can't always rely on those values
to decide whether the resolved target can handle any new DFS
referrals.
Add a new helper is_referral_server() to check if all resolved targets
can handle new DFS referrals by directly looking at the
GET_DFS_REFERRAL.ReferralHeaderFlags value as specified in MS-DFSC
2.2.4 RESP_GET_DFS_REFERRAL in addition to is_tcon_dfs().
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@vger.kernel.org # 5.11 Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Handle the case where a resolved target share is like
//server/users/dir, and the user "foo" has no read permission to
access the parent folder "users" but has access to the final path
component "dir".
is_path_remote() already implements that, so call it directly.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@vger.kernel.org # 5.11 Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In do_dfs_failover(), the mount_get_conns() function requires the full
fs context in order to get new connection to server, so clone the
original context and change it accordingly when retrying the DFS
targets in the referral.
If failover was successful, then update original context with the new
UNC, prefix path and ip address.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Cc: stable@vger.kernel.org # 5.11 Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During checkpoint=disable period, f2fs bypasses all the synchronous IOs such as
sync and fsync. So, when enabling it back, we must flush all of them in order
to keep the data persistent. Otherwise, suddern power-cut right after enabling
checkpoint will cause data loss.
This patch ports commit 02b016ca7f99 ("ext4: enforce the immutable
flag on open files") to f2fs.
According to the chattr man page, "a file with the 'i' attribute
cannot be modified..." Historically, this was only enforced when the
file was opened, per the rest of the description, "... and the file
can not be opened in write mode".
There is general agreement that we should standardize all file systems
to prevent modifications even for files that were opened at the time
the immutable flag is set. Eventually, a change to enforce this at
the VFS layer should be landing in mainline.
Currently we use bitmap_alloc() to allocate msi bitmap which should be
initialized with zero. This is obviously wrong but it works because msi
can fallback to legacy interrupt mode. So use bitmap_zalloc() instead.
In some cases we can get to fix_range_common() with mmap_sem held,
and in others we get there without it being held. For example, we
get there with it held from sys_mprotect(), and without it held
from fork_handler().
Avoid any issues in this and simply defer killing the task until
it runs the next time. Do it on the mm so that another task that
shares the same mm can't continue running afterwards.
Cc: stable@vger.kernel.org Fixes: 468f65976a8d ("um: Fix hung task in fix_range_common()") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If userspace tries to change the stub, we need to kill it,
because otherwise it can escape the virtual machine. In a
few cases the stub checks weren't good, e.g. if userspace
just tries to
mmap(0x100000 - 0x1000, 0x3000, ...)
it could succeed to get a new private/anonymous mapping
replacing the stubs. Fix this by checking everywhere, and
checking for _overlap_, not just direct changes.
Cc: stable@vger.kernel.org Fixes: 3963333fe676 ("uml: cover stubs with a VMA") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CCW_CMD_READ_STATUS was introduced with revision 2 of virtio-ccw,
and drivers should only rely on it being implemented when they
negotiated at least that revision with the device.
However, virtio_ccw_get_status() issued READ_STATUS for any
device operating at least at revision 1. If the device accepts
READ_STATUS regardless of the negotiated revision (which some
implementations like QEMU do, even though the spec currently does
not allow it), everything works as intended. While a device
rejecting the command should also be handled gracefully, we will
not be able to see any changes the device makes to the status,
such as setting NEEDS_RESET or setting the status to zero after
a completed reset.
We negotiated the revision to at most 1, as we never bumped the
maximum revision; let's do that now and properly send READ_STATUS
only if we are operating at least at revision 2.
The stck/stckf instruction used within the inline assembly within
do_account_vtime() changes the condition code. This is not reflected
with the clobber list, and therefore might result in incorrect code
generation.
It seems unlikely that the compiler could generate incorrect code
considering the surrounding C code, but it must still be fixed.
If this is attempted by an io-wq kthread, then return -EOPNOTSUPP as we
don't currently support that. Once we can get task_pid_ptr() doing the
right thing, then this can go away again.
Use PF_IO_WORKER for this to speciically target the io_uring workers.
Modify the /proc/self/ check to use PF_IO_WORKER as well.
Cc: stable@vger.kernel.org Fixes: 8d4c3e76e3be ("proc: don't allow async path resolution of /proc/self components") Reported-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, when turbo is disabled (either by BIOS or by the user),
the intel_pstate driver reads the max non-turbo frequency from the
package-wide MSR_PLATFORM_INFO(0xce) register.
However, on asymmetric platforms it is possible in theory that small
and big core with HWP enabled might have different max non-turbo CPU
frequency, because MSR_HWP_CAPABILITIES is per-CPU scope according
to Intel Software Developer Manual.
The turbo max freq is already per-CPU in current code, so make
similar change to the max non-turbo frequency as well.
Reported-by: Wendy Wang <wendy.wang@intel.com> Signed-off-by: Chen Yu <yu.c.chen@intel.com>
[ rjw: Subject and changelog edits ] Cc: 4.18+ <stable@vger.kernel.org> # 4.18+: a45ee4d4e13b: cpufreq: intel_pstate: Change intel_pstate_get_hwp_max() argument Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All of the callers of intel_pstate_get_hwp_max() access the struct
cpudata object that corresponds to the given CPU already and the
function itself needs to access that object (in order to update
hwp_cap_cached), so modify the code to pass a struct cpudata pointer
to it instead of the CPU number.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f17b3e44320b ("cpufreq: qcom-hw: Use
devm_platform_ioremap_resource() to simplify code") introduces
a regression on platforms using the driver, by failing to initialise
a policy, when one is created post hotplug.
When all the CPUs of a policy are hoptplugged out, the call to .exit()
and later to devm_iounmap() does not release the memory region that was
requested during devm_platform_ioremap_resource(). Therefore,
a subsequent call to .init() will result in the following error, which
will prevent a new policy to be initialised:
With that being said, the original code was tricky and skipping memory
region request intentionally to hide this issue. The true cause is that
those devm_xxx() device managed functions shouldn't be used for cpufreq
init/exit hooks, because &pdev->dev is alive across the hooks and will
not trigger auto resource free-up. Let's drop the use of device managed
functions and manually allocate/free resources, so that the issue can be
fixed properly.
freq_qos_update_request() returns 1 if the effective constraint value
has changed, 0 if the effective constraint value has not changed, or a
negative error code on failures.
The frequency constraints for CPUs can be set by different parts of the
kernel. If the maximum frequency constraint set by other parts of the
kernel are set at a lower value than the one corresponding to cooling
state 0, then we will never be able to cool down the system as
freq_qos_update_request() will keep on returning 0 and we will skip
updating cpufreq_state and thermal pressure.
Fix that by doing the updates even in the case where
freq_qos_update_request() returns 0, as we have effectively set the
constraint to a new value even if the consolidated value of the
actual constraint is unchanged because of external factors.
Cc: v5.7+ <stable@vger.kernel.org> # v5.7+ Reported-by: Thara Gopinath <thara.gopinath@linaro.org> Fixes: f12e4f66ab6a ("thermal/cpu-cooling: Update thermal pressure in case of a maximum frequency capping") Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Thara Gopinath<thara.gopinath@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/b2b7e84944937390256669df5a48ce5abba0c1ef.1613540713.git.viresh.kumar@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Userspace has discovered the functionality offered by SYS_kcmp and has
started to depend upon it. In particular, Mesa uses SYS_kcmp for
os_same_file_description() in order to identify when two fd (e.g. device
or dmabuf) point to the same struct file. Since they depend on it for
core functionality, lift SYS_kcmp out of the non-default
CONFIG_CHECKPOINT_RESTORE into the selectable syscall category.
Rasmus Villemoes also pointed out that systemd uses SYS_kcmp to
deduplicate the per-service file descriptor store.
Note that some distributions such as Ubuntu are already enabling
CHECKPOINT_RESTORE in their configs and so, by extension, SYS_kcmp.
References: https://gitlab.freedesktop.org/drm/intel/-/issues/3046 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Will Drewry <wad@chromium.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dave Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Lucas Stach <l.stach@pengutronix.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Cc: stable@vger.kernel.org Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> # DRM depends on kcmp Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> # systemd uses kcmp Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20210205220012.1983-1-chris@chris-wilson.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Per ZBC/ZAC/ZNS specifications, write pointers may not have valid values
when zones are in full condition. However, when zonefs mounts a zoned
block device, zonefs refers write pointers to set file size even when
the zones are in full condition. This results in wrong file size. To fix
this, refer maximum file size in place of write pointers for zones in
full condition.
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Fixes: 8dcc1a9d90c1 ("fs: New zonefs file system") Cc: <stable@vger.kernel.org> # 5.6+ Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
exfat specification describe sect_per_clus_bits field of boot sector
could be at most 25 - sect_size_bits and at least 0. And sect_size_bits
can also affect this calculation, It also needs validation.
This patch add validation for sect_per_clus_bits and sect_size_bits
field of boot sector.
Fixes: 719c1e182916 ("exfat: add super block operations") Cc: stable@vger.kernel.org # v5.9+ Reported-by: syzbot+da4fe66aaadd3c2e2d1c@syzkaller.appspotmail.com Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
printk_safe_flush_on_panic() caused the following deadlock on our
server:
CPU0: CPU1:
panic rcu_dump_cpu_stacks
kdump_nmi_shootdown_cpus nmi_trigger_cpumask_backtrace
register_nmi_handler(crash_nmi_callback) printk_safe_flush
__printk_safe_flush
raw_spin_lock_irqsave(&read_lock)
// send NMI to other processors
apic_send_IPI_allbutself(NMI_VECTOR)
// NMI interrupt, dead loop
crash_nmi_callback
printk_safe_flush_on_panic
printk_safe_flush
__printk_safe_flush
// deadlock
raw_spin_lock_irqsave(&read_lock)
DEADLOCK: read_lock is taken on CPU1 and will never get released.
It happens when panic() stops a CPU by NMI while it has been in
the middle of printk_safe_flush().
Handle the lock the same way as logbuf_lock. The printk_safe buffers
are flushed only when both locks can be safely taken. It can avoid
the deadlock _in this particular case_ at expense of losing contents
of printk_safe buffers.
Note: It would actually be safe to re-init the locks when all CPUs were
stopped by NMI. But it would require passing this information
from arch-specific code. It is not worth the complexity.
Especially because logbuf_lock and printk_safe buffers have been
obsoleted by the lockless ring buffer.
Fixes: cf9b1106c81c ("printk/nmi: flush NMI messages on the system panic") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: <stable@vger.kernel.org> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20210210034823.64867-1-songmuchun@bytedance.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If no n_latch value will be provided at driver probe then all pins will
be used as an input:
gpio->out = ~n_latch;
In that case initial state for all pins is "one":
gpio->status = gpio->out;
So if pcf857x IRQ happens with change pin value from "zero" to "one"
then we miss it, because of "one" from IRQ and "one" from initial state
leaves corresponding pin unchanged:
change = (gpio->status ^ status) & gpio->irq_enabled;
The right solution will be to read actual state at driver probe.
The size in header field for packet transferred over DMA
includes size of the extended header.
Include extended header in size check.
Add size and sanity checks on extended header.
Cc: <stable@vger.kernel.org> # v5.10+ Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Link: https://lore.kernel.org/r/20210129120752.850325-1-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, when handling the SPMI summary interrupt, the hw_irq
number is calculated based on SID, Peripheral ID, IRQ index and
APID. This is then passed to irq_find_mapping() to see if a
mapping exists for this hw_irq and if available, invoke the
interrupt handler. Since the IRQ index uses an "int" type, hw_irq
which is of unsigned long data type can take a large value when
SID has its MSB set to 1 and the type conversion happens. Because
of this, irq_find_mapping() returns 0 as there is no mapping
for this hw_irq. This ends up invoking cleanup_irq() as if
the interrupt is spurious whereas it is actually a valid
interrupt. Fix this by using the proper data type (u32) for id.
Userspace Execution protection and fast syscall entry were implemented
independently from each other and were both merged in kernel 5.2,
leading to syscall entry missing userspace execution protection.
On syscall entry, execution of user space memory must be
locked in the same way as on exception entry.
On systems with large amount of memory, loading kdump kernel through
kexec_file_load syscall may fail with the below error:
"Failed to update fdt with linux,drconf-usable-memory property"
This happens because the size estimation for kdump kernel's FDT does
not account for the additional space needed to setup usable memory
properties. Fix it by accounting for the space needed to include
linux,usable-memory & linux,drconf-usable-memory properties while
estimating kdump kernel's FDT size.
Fixes: 6ecd0163d360 ("powerpc/kexec_file: Add appropriate regions for memory reserve map") Cc: stable@vger.kernel.org # v5.9+ Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/161243826811.119001.14083048209224609814.stgit@hbathini Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
THREAD_ALIGN_SHIFT = THREAD_SHIFT + 1 = PAGE_SHIFT + 1
Maximum PAGE_SHIFT is 18 for 256k pages so
THREAD_ALIGN_SHIFT is 19 at the maximum.
No need to clobber cr1, it can be preserved when moving r1
into CR when we check stack overflow.
This reduces the number of instructions in Machine Check Exception
prolog and fixes a build failure reported by the kernel test robot
on v5.10 stable when building with RTAS + VMAP_STACK + KVM. That
build failure is due to too many instructions in the prolog hence
not fitting between 0x200 and 0x300. Allthough the problem doesn't
show up in mainline, it is still worth the change.
In sdhci_esdhc_imx_remove() the SDHCI_INT_STATUS in read. Under some
circumstances, this may be done while the device is runtime suspended,
triggering the below splat.
Fix the problem by adding a pm_runtime_get_sync(), before reading the
register, which will turn on clocks etc making the device accessible again.
clang-12 -fno-pic (since
https://github.com/llvm/llvm-project/commit/a084c0388e2a59b9556f2de0083333232da3f1d6)
can emit `call __stack_chk_fail@PLT` instead of `call __stack_chk_fail`
on x86. The two forms should have identical behaviors on x86-64 but the
former causes GNU as<2.37 to produce an unreferenced undefined symbol
_GLOBAL_OFFSET_TABLE_.
(On x86-32, there is an R_386_PC32 vs R_386_PLT32 difference but the
linker behavior is identical as far as Linux kernel is concerned.)
Simply ignore _GLOBAL_OFFSET_TABLE_ for now, like what
scripts/mod/modpost.c:ignore_undef_symbol does. This also fixes the
problem for gcc/clang -fpie and -fpic, which may emit `call foo@PLT` for
external function calls on x86.
Note: ld -z defs and dynamic loaders do not error for unreferenced
undefined symbols so the module loader is reading too much. If we ever
need to ignore more symbols, the code should be refactored to ignore
unreferenced symbols.
Cc: <stable@vger.kernel.org> Link: https://github.com/ClangBuiltLinux/linux/issues/1250 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=27178 Reported-by: Marco Elver <elver@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Marco Elver <elver@google.com> Signed-off-by: Fangrui Song <maskray@google.com> Signed-off-by: Jessica Yu <jeyu@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
"sdam->pdev" is uninitialized and it is used to print error logs.
Fix it. Since device pointer can be used from sdam_config, use it
directly thereby removing pdev pointer.
Compaction always operates on pages from a single given zone when
isolating both pages to migrate and freepages. Pageblock boundaries are
intersected with zone boundaries to be safe in case zone starts or ends in
the middle of pageblock. The use of pageblock_pfn_to_page() protects
against non-contiguous pageblocks.
The functions fast_isolate_freepages() and fast_isolate_around() don't
currently protect the fast freepage isolation thoroughly enough against
these corner cases, and can result in freepage isolation operate outside
of zone boundaries:
- in fast_isolate_freepages() if we get a pfn from the first pageblock
of a zone that starts in the middle of that pageblock, 'highest' can
be a pfn outside of the zone.
If we fail to isolate anything in this function, we may then call
fast_isolate_around() on a pfn outside of the zone and there
effectively do a set_pageblock_skip(page_to_pfn(highest)) which may
currently hit a VM_BUG_ON() in some configurations
- fast_isolate_around() checks only the zone end boundary and not
beginning, nor that the pageblock is contiguous (with
pageblock_pfn_to_page()) so it's possible that we end up calling
isolate_freepages_block() on a range of pfn's from two different
zones and end up e.g. isolating freepages under the wrong zone's
lock.
This patch should fix the above issues.
Link: https://lkml.kernel.org/r/20210217173300.6394-1-vbabka@suse.cz Fixes: 5a811889de10 ("mm, compaction: use free lists to quickly locate a migration target") Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> 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>
I went to go add a new RECLAIM_* mode for the zone_reclaim_mode sysctl.
Like a good kernel developer, I also went to go update the
documentation. I noticed that the bits in the documentation didn't
match the bits in the #defines.
The VM never explicitly checks the RECLAIM_ZONE bit. The bit is,
however implicitly checked when checking 'node_reclaim_mode==0'. The
RECLAIM_ZONE #define was removed in a cleanup. That, by itself is fine.
But, when the bit was removed (bit 0) the _other_ bit locations also got
changed. That's not OK because the bit values are documented to mean
one specific thing. Users surely do not expect the meaning to change
from kernel to kernel.
The end result is that if someone had a script that did:
sysctl vm.zone_reclaim_mode=1
it would have gone from enabling node reclaim for clean unmapped pages
to writing out pages during node reclaim after the commit in question.
That's not great.
Put the bits back the way they were and add a comment so something like
this is a bit harder to do again. Update the documentation to make it
clear that the first bit is ignored.
Link: https://lkml.kernel.org/r/20210219172555.FF0CDF23@viggo.jf.intel.com Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Fixes: 648b5cf368e0 ("mm/vmscan: remove unused RECLAIM_OFF/RECLAIM_ZONE") Reviewed-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Alex Shi <alex.shi@linux.alibaba.com> Cc: Daniel Wagner <dwagner@suse.de> Cc: "Tobin C. Harding" <tobin@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Qian Cai <cai@lca.pw> 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>
page structs are not guaranteed to be contiguous for gigantic pages. The
routine copy_huge_page_from_user can encounter gigantic pages, yet it
assumes page structs are contiguous when copying pages from user space.
Since page structs for the target gigantic page are not contiguous, the
data copied from user space could overwrite other pages not associated
with the gigantic page and cause data corruption.
Non-contiguous page structs are generally not an issue. However, they can
exist with a specific kernel configuration and hotplug operations. For
example: Configure the kernel with CONFIG_SPARSEMEM and
!CONFIG_SPARSEMEM_VMEMMAP. Then, hotplug add memory for the area where
the gigantic page will be allocated.
Link: https://lkml.kernel.org/r/20210217184926.33567-2-mike.kravetz@oracle.com Fixes: 8fb5debc5fcd ("userfaultfd: hugetlbfs: add hugetlb_mcopy_atomic_pte for userfaultfd support") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Joao Martins <joao.m.martins@oracle.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>
page structs are not guaranteed to be contiguous for gigantic pages. The
routine update_and_free_page can encounter a gigantic page, yet it assumes
page structs are contiguous when setting page flags in subpages.
If update_and_free_page encounters non-contiguous page structs, we can see
“BUG: Bad page state in process …” errors.
Non-contiguous page structs are generally not an issue. However, they can
exist with a specific kernel configuration and hotplug operations. For
example: Configure the kernel with CONFIG_SPARSEMEM and
!CONFIG_SPARSEMEM_VMEMMAP. Then, hotplug add memory for the area where
the gigantic page will be allocated. Zi Yan outlined steps to reproduce
here [1].
Link: https://lkml.kernel.org/r/20210217184926.33567-1-mike.kravetz@oracle.com Fixes: 944d9fec8d7a ("hugetlb: add support for gigantic page allocation at runtime") Signed-off-by: Zi Yan <ziy@nvidia.com> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Joao Martins <joao.m.martins@oracle.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>
We use a global percpu int_active_memcg variable to store the remote memcg
when we are in the interrupt context. But get_active_memcg always return
the current->active_memcg or root_mem_cgroup. The remote memcg (set in
the interrupt context) is ignored. This is not what we want. So fix it.
Link: https://lkml.kernel.org/r/20210223091101.42150-1-songmuchun@bytedance.com Fixes: 37d5985c003d ("mm: kmem: prepare remote memcg charging infra for interrupt contexts") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Reviewed-by: Roman Gushchin <guro@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@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 pages are swapped in, the VM may retain the swap copy to avoid
repeated writes in the future. It's also retained if shared pages are
faulted back in some processes, but not in others. During that time we
have an in-memory copy of the page, as well as an on-swap copy. Cgroup1
and cgroup2 handle these overlapping lifetimes slightly differently due to
the nature of how they account memory and swap:
Cgroup1 has a unified memory+swap counter that tracks a data page
regardless whether it's in-core or swapped out. On swapin, we transfer
the charge from the swap entry to the newly allocated swapcache page, even
though the swap entry might stick around for a while. That's why we have
a mem_cgroup_uncharge_swap() call inside mem_cgroup_charge().
Cgroup2 tracks memory and swap as separate, independent resources and thus
has split memory and swap counters. On swapin, we charge the newly
allocated swapcache page as memory, while the swap slot in turn must
remain charged to the swap counter as long as its allocated too.
The cgroup2 logic was broken by commit 2d1c498072de ("mm: memcontrol: make
swap tracking an integral part of memory control"), because it
accidentally removed the do_memsw_account() check in the branch inside
mem_cgroup_uncharge() that was supposed to tell the difference between the
charge transfer in cgroup1 and the separate counters in cgroup2.
As a result, cgroup2 currently undercounts retained swap to varying
degrees: swap slots are cached up to 50% of the configured limit or total
available swap space; partially faulted back shared pages are only limited
by physical capacity. This in turn allows cgroups to significantly
overconsume their alloted swap space.
Add the do_memsw_account() check back to fix this problem.
Link: https://lkml.kernel.org/r/20210217153237.92484-1-songmuchun@bytedance.com Fixes: 2d1c498072de ("mm: memcontrol: make swap tracking an integral part of memory control") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <stable@vger.kernel.org> [5.8+] 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 memtype seq_file iterator allocates a buffer in the ->start and ->next
functions and frees it in the ->show function. The preferred handling for
such resources is to free them in the subsequent ->next or ->stop function
call.
Since Commit 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration
code and interface") there is no guarantee that ->show will be called
after ->next, so this function can now leak memory.
So move the freeing of the buffer to ->next and ->stop.
Link: https://lkml.kernel.org/r/161248539022.21478.13874455485854739066.stgit@noble1 Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface") Signed-off-by: NeilBrown <neilb@suse.de> Cc: Xin Long <lucien.xin@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vlad Yasevich <vyasevich@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>
Patch series "Fix some seq_file users that were recently broken".
A recent change to seq_file broke some users which were using seq_file
in a non-"standard" way ... though the "standard" isn't documented, so
they can be excused. The result is a possible leak - of memory in one
case, of references to a 'transport' in the other.
These three patches:
1/ document and explain the problem
2/ fix the problem user in x86
3/ fix the problem user in net/sctp
This patch (of 3):
Users of seq_file will sometimes find it convenient to take a resource,
such as a lock or memory allocation, in the ->start or ->next operations.
These are per-entry resources, distinct from per-session resources which
are taken in ->start and released in ->stop.
The preferred management of these is release the resource on the
subsequent call to ->next or ->stop.
However prior to Commit 1f4aace60b0e ("fs/seq_file.c: simplify seq_file
iteration code and interface") it happened that ->show would always be
called after ->start or ->next, and a few users chose to release the
resource in ->show.
This is no longer reliable. Since the mentioned commit, ->next will
always come after a successful ->show (to ensure m->index is updated
correctly), so the original ordering cannot be maintained.
This patch updates the documentation to clearly state the required
behaviour. Other patches will fix the few problematic users.
[akpm@linux-foundation.org: fix typo, per Willy]
Link: https://lkml.kernel.org/r/161248518659.21478.2484341937387294998.stgit@noble1 Link: https://lkml.kernel.org/r/161248539020.21478.3147971477400875336.stgit@noble1 Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface") Signed-off-by: NeilBrown <neilb@suse.de> Cc: Xin Long <lucien.xin@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> 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>
Even if erase type is same as previous region, erase size can be different
if the previous region is overlaid region. Since 'region->size' is assigned
to 'cmd->size' for overlaid region, comparing 'erase->size' and 'cmd->size'
can detect previous overlaid region.
Fixes: 5390a8df769e ("mtd: spi-nor: add support to non-uniform SFDP SPI NOR flash memories") Cc: stable@vger.kernel.org Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
[ta: Add Fixes tag and Cc to stable] Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Link: https://lore.kernel.org/r/13d47e8d8991b8a7fd8cc7b9e2a5319c56df35cc.1601612872.git.Takahiro.Kuwano@infineon.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of overlaid regions in which their biggest erase size command
overpasses in size the region's size, only the non-overlaid portion of
the sector gets erased. For example, if a Sector Erase command is applied
to a 256-kB range that is overlaid by 4-kB sectors, the overlaid 4-kB
sectors are not affected by the erase.
For overlaid regions, 'region->size' is assigned to 'cmd->size' later in
spi_nor_init_erase_cmd(), so 'erase->size' can be greater than 'len'.
Fixes: 5390a8df769e ("mtd: spi-nor: add support to non-uniform SFDP SPI NOR flash memories") Cc: stable@vger.kernel.org Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
[ta: Update commit description, add Fixes tag and Cc to stable] Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Link: https://lore.kernel.org/r/fa5d8b944a5cca488ac54ba37c95e775ac2deb34.1601612872.git.Takahiro.Kuwano@infineon.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At the time spi_nor_region_check_overlay() is called, the erase types are
sorted in ascending order of erase size. The 'erase_type' should be masked
with 'BIT(erase[i].idx)' instead of 'BIT(i)'.
Fixes: b038e8e3be72 ("mtd: spi-nor: parse SFDP Sector Map Parameter Table") Cc: stable@vger.kernel.org Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
[ta: Add Fixes tag and Cc to stable] Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Link: https://lore.kernel.org/r/fd90c40d5b626a1319a78fc2bcee79a8871d4d57.1601612872.git.Takahiro.Kuwano@infineon.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The MEI bus has a special behavior on suspend it destroys
all the attached devices, this is due to the fact that also
firmware context is not persistent across power flows.
If watchdog on MEI bus is ticking before suspending the firmware
times out and reports that the OS is missing watchdog tick.
Send the stop command to the firmware on watchdog unregistered
to eliminate the false event on suspend.
This does not make the things worse from the user-space perspective
as a user-space should re-open watchdog device after
suspending before this patch.
Cc: <stable@vger.kernel.org> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20210124114938.373885-1-tomas.winkler@intel.com Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As per register documentation, QCOM_WDT_ENABLE_IRQ which is BIT(1)
of watchdog control register is wakeup interrupt enable bit and
not related to bark interrupt at all, BIT(0) is used for that.
So remove incorrect usage of this bit when supporting bark irq for
pre-timeout notification. Currently with this bit set and bark
interrupt specified, pre-timeout notification and/or watchdog
reset/bite does not occur.
Fixes: 36375491a439 ("watchdog: qcom: support pre-timeout when the bark irq is available") Cc: stable@vger.kernel.org Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Link: https://lore.kernel.org/r/20210126150241.10009-1-saiprakash.ranjan@codeaurora.org Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We use the generic C VDSO implementations of a handful of clock-related
functions. When kasan is enabled this results in asan stub calls that
are unlikely to be resolved by userspace, this just disables KASAN
when building the VDSO.
Verified the fix on a kernel with KASAN enabled using vDSO selftests.
Link: https://lore.kernel.org/lkml/CACT4Y+ZNJBnkKHXUf=tm_yuowvZvHwN=0rmJ=7J+xFd+9r_6pQ@mail.gmail.com/ Tested-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Tested-by: Dmitry Vyukov <dvyukov@google.com>
[Palmer: commit text] Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Spectre-v4 workaround is re-configured when resuming from suspend,
as the firmware may have re-enabled the mitigation despite the user
previously asking for it to be disabled.
Enabling or disabling the workaround can result in an undefined
instruction exception on CPUs which implement PSTATE.SSBS but only allow
it to be configured by adjusting the SPSR on exception return. We handle
this by installing an 'undef hook' which effectively emulates the access.
Installing this hook requires us to take a couple of spinlocks both to
avoid corrupting the internal list of hooks but also to ensure that we
don't run into an unhandled exception. Unfortunately, when resuming from
suspend, we haven't yet called rcu_idle_exit() and so lockdep gets angry
about "suspicious RCU usage". In doing so, it tries to print a warning,
which leads it to get even more suspicious, this time about itself:
These plt* and .text.ftrace_trampoline sections specified for arm64 have
non-zero addressses. Non-zero section addresses in a relocatable ELF would
confuse GDB when it tries to compute the section offsets and it ends up
printing wrong symbol addresses. Therefore, set them to zero, which mirrors
the change in commit 5d8591bc0fba ("module: set ksymtab/kcrctab* section
addresses to 0x0").
Reported-by: Frank van der Linden <fllinden@amazon.com> Signed-off-by: Shaoying Xu <shaoyi@amazon.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20210216183234.GA23876@amazon.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As stated in linux/errno.h, ENOTSUPP should never be seen by user programs.
When we set up uprobe with 32-bit perf and arm64 kernel, we would see the
following vague error without useful hint.
The sys_perf_event_open() syscall returned with 524 (INTERNAL ERROR:
strerror_r(524, [buf], 128)=22)
When extracting the mask for a SMR that was programmed by the
bootloader, the SMR's valid bit is also extracted and is treated
as part of the mask, which is not correct. Consider the scenario
where an SMMU master whose context is determined by a bootloader
programmed SMR is removed (omitting parts of device/driver core):
->iommu_release_device()
-> arm_smmu_release_device()
-> arm_smmu_master_free_smes()
-> arm_smmu_free_sme() /* Assume that the SME is now free */
-> arm_smmu_write_sme()
-> arm_smmu_write_smr() /* Construct SMR value using mask and SID */
Since the valid bit was considered as part of the mask, the SMR will
be programmed as valid.
Fix the SMR mask extraction step for bootloader programmed SMRs
by masking out the valid bit when we know that we're already
working with a valid SMR.
Fixes: 07a7f2caaa5a ("iommu/arm-smmu-qcom: Read back stream mappings") Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org> Cc: stable@vger.kernel.org Reviewed-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/1611611545-19055-1-git-send-email-isaacm@codeaurora.org Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The erratum 1024718 affects Cortex-A55 r0p0 to r2p0. However
we apply the work around for r0p0 - r1p0. Unfortunately this
won't be fixed for the future revisions for the CPU. Thus
extend the work around for all versions of A55, to cover
for r2p0 and any future revisions.
Cc: stable@vger.kernel.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20210203230057.3961239-1-suzuki.poulose@arm.com
[will: Update Kconfig help text] Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 36dadef23fcc ("kprobes: Init kprobes in early_initcall")
moved the kprobe setup in early_initcall(), which includes kprobe
jump optimization.
The kprobes jump optimizer involves synchronize_rcu_tasks() which
depends on the ksoftirqd and rcu_spawn_tasks_*(). However, since
those are setup in core_initcall(), kprobes jump optimizer can not
run at the early_initcall().
To avoid this issue, make the kprobe optimization disabled in the
early_initcall() and enables it in subsys_initcall().
Note that non-optimized kprobes is still available after
early_initcall(). Only jump optimization is delayed.
Link: https://lkml.kernel.org/r/161365856280.719838.12423085451287256713.stgit@devnote2 Fixes: 36dadef23fcc ("kprobes: Init kprobes in early_initcall") Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: RCU <rcu@vger.kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Daniel Axtens <dja@axtens.net> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Neeraj Upadhyay <neeraju@codeaurora.org> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Michal Hocko <mhocko@suse.com> Cc: "Theodore Y . Ts'o" <tytso@mit.edu> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com> Cc: stable@vger.kernel.org Reported-by: Paul E. McKenney <paulmck@kernel.org> Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reported-by: Uladzislau Rezki <urezki@gmail.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Following the idle loop model, cleanly check for pending rcuog wakeup
before the last rescheduling point upon resuming to guest mode. This
way we can avoid to do it from rcu_user_enter() with the last resort
self-IPI hack that enforces rescheduling.
Following the idle loop model, cleanly check for pending rcuog wakeup
before the last rescheduling point on resuming to user mode. This
way we can avoid to do it from rcu_user_enter() with the last resort
self-IPI hack that enforces rescheduling.
Entering RCU idle mode may cause a deferred wake up of an RCU NOCB_GP
kthread (rcuog) to be serviced.
Unfortunately the call to rcu_user_enter() is already past the last
rescheduling opportunity before we resume to userspace or to guest mode.
We may escape there with the woken task ignored.
The ultimate resort to fix every callsites is to trigger a self-IPI
(nohz_full depends on arch to implement arch_irq_work_raise()) that will
trigger a reschedule on IRQ tail or guest exit.
Eventually every site that want a saner treatment will need to carefully
place a call to rcu_nocb_flush_deferred_wakeup() before the last explicit
need_resched() check upon resume.
Fixes: 96d3fd0d315a (rcu: Break call_rcu() deadlock involving scheduler and perf) Reported-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20210131230548.32970-4-frederic@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / linux-stable / log