I was a little overzealous in removing the rcu_read_lock() call from
blkcg_bio_issue_check() and it broke blk-throttle. Put it back.
Fixes: e35403a034bf ("blkcg: associate blkg when associating a device")
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that we have this common helper, convert io-latency over to use it
as well.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that we have rq_qos_wait() in place, convert wbt_wait() over to
using it with it's specific callbacks.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Originally when I split out the common code from blk-wbt into rq_qos I
left the wbt_wait() where it was and simply copied and modified it
slightly to work for io-latency. However they are both basically the
same thing, and as time has gone on wbt_wait() has ended up much smarter
and kinder than it was when I copied it into io-latency, which means
io-latency has lost out on these improvements.
Since they are the same thing essentially except for a few minor things,
create rq_qos_wait() that replicates what wbt_wait() currently does with
callbacks that can be passed in for the snowflakes to do their own thing
as appropriate.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blkg reference counting now uses percpu_ref rather than atomic_t. Let's
make this consistent with css_tryget. This renames blkg_try_get to
blkg_tryget and now returns a bool rather than the blkg or %NULL.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Every bio is now associated with a blkg putting blkg_get, blkg_try_get,
and blkg_put on the hot path. Switch over the refcnt in blkg to use
percpu_ref.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that a bio only holds a blkg reference, so clean up is simply
putting back that reference. Remove bio_disassociate_task() as it just
calls bio_disassociate_blkg() and call the latter directly.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The previous patch in this series removed carrying around a pointer to
the css in blkg. However, the blkg association logic still relied on
taking a reference on the css to ensure we wouldn't fail in getting a
reference for the blkg.
Here the implicit dependency on the css is removed. The association
continues to rely on the tryget logic walking up the blkg tree. This
streamlines the three ways that association can happen: normal, swap,
and writeback.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Prior patches ensured that any bio that interacts with a request_queue
is properly associated with a blkg. This makes bio->bi_css unnecessary
as blkg maintains a reference to blkcg already.
This removes the bio field bi_css and transfers corresponding uses to
access via bi_blkg.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
One of the goals of this series is to remove a separate reference to
the css of the bio. This can and should be accessed via bio_blkcg(). In
this patch, wbc_init_bio() now requires a bio to have a device
associated with it.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A prior patch in this series added blkg association to bios issued by
cgroups. There are two other paths that we want to attribute work back
to the appropriate cgroup: swap and writeback. Here we modify the way
swap tags bios to include the blkg. Writeback will be tackle in the next
patch.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bio_issue_init among other things initializes the timestamp for an IO.
Rather than have this logic handled by policies, this consolidates it to
be on the init paths (normal, clone, bounce clone).
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Previously, blkg association was handled by controller specific code in
blk-throttle and blk-iolatency. However, because a blkg represents a
relationship between a blkcg and a request_queue, it makes sense to keep
the blkg->q and bio->bi_disk->queue consistent.
This patch moves association into the bio_set_dev macro(). This should
cover the majority of cases where the device is set/changed keeping the
two pointers consistent. Fallback code is added to
blkcg_bio_issue_check() to catch any missing paths.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The next patch changes the macro bio_set_dev() to associate a bio with a
blkg based on the device set. However, dm creates a static bio to be
used as the basis for cloning empty flush bios on creation. The
bio_set_dev() call in alloc_dev() will cause problems with the next
patch adding association to bio_set_dev() because the call is before the
bdev is associated with a gendisk (bd_disk is %NULL). To get around
this, set the device on the static bio every time and use that to clone
to the other bios.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Cc: Alasdair Kergon <agk@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are 3 ways blkg association can happen: association with the
current css, with the page css (swap), or from the wbc css (writeback).
This patch handles how association is done for the first case where we
are associating bsaed on the current css. If there is already a blkg
associated, the css will be reused and association will be redone as the
request_queue may have changed.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are several scenarios where blkg_lookup_create() can fail such as
the blkcg dying, request_queue is dying, or simply being OOM. Most
handle this by simply falling back to the q->root_blkg and calling it a
day.
This patch implements the notion of closest blkg. During
blkg_lookup_create(), if it fails to create, return the closest blkg
found or the q->root_blkg. blkg_try_get_closest() is introduced and used
during association so a bio is always attached to a blkg.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To know when to create a blkg, the general pattern is to do a
blkg_lookup() and if that fails, lock and do the lookup again, and if
that fails finally create. It doesn't make much sense for everyone who
wants to do creation to write this themselves.
This changes blkg_lookup_create() to do locking and implement this
pattern. The old blkg_lookup_create() is renamed to
__blkg_lookup_create(). If a call site wants to do its own error
handling or already owns the queue lock, they can use
__blkg_lookup_create(). This will be used in upcoming patches.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The bio_blkcg() function turns out to be inconsistent and consequently
dangerous to use. The first part returns a blkcg where a reference is
owned by the bio meaning it does not need to be rcu protected. However,
the third case, the last line, is problematic:
return css_to_blkcg(task_css(current, io_cgrp_id));
This can race against task migration and the cgroup dying. It is also
semantically different as it must be called rcu protected and is
susceptible to failure when trying to get a reference to it.
This patch adds association ahead of calling bio_blkcg() rather than
after. This makes association a required and explicit step along the
code paths for calling bio_blkcg(). In blk-iolatency, association is
moved above the bio_blkcg() call to ensure it will not return %NULL.
BFQ uses the old bio_blkcg() function, but I do not want to address it
in this series due to the complexity. I have created a private version
documenting the inconsistency and noting not to use it.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We only support polling if we have poll queues now, but the flag is
being set by default. Remove the default QUEUE_FLAG_POLL setting, we'll
set it in blk_mq_init_allocated_queue() if we have poll queues available
for this device.
Fixes: 6544d229bf ("block: enable polling by default if a poll map is initalized")
Reported-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stefano Brivio says:
====================
Fix slab out-of-bounds on insufficient headroom for IPv6 packets
Patch 1/2 fixes a slab out-of-bounds occurring with short SCTP packets over
IPv4 over L2TP over IPv6 on a configuration with relatively low HEADER_MAX.
Patch 2/2 makes sure we avoid writing before the allocated buffer in
neigh_hh_output() in case the headroom is enough for the unaligned hardware
header size, but not enough for the aligned one, and that we warn if we hit
this condition.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
While skb_push() makes the kernel panic if the skb headroom is less than
the unaligned hardware header size, it will proceed normally in case we
copy more than that because of alignment, and we'll silently corrupt
adjacent slabs.
In the case fixed by the previous patch,
"ipv6: Check available headroom in ip6_xmit() even without options", we
end up in neigh_hh_output() with 14 bytes headroom, 14 bytes hardware
header and write 16 bytes, starting 2 bytes before the allocated buffer.
Always check we're not writing before skb->head and, if the headroom is
not enough, warn and drop the packet.
v2:
- instead of panicking with BUG_ON(), WARN_ON_ONCE() and drop the packet
(Eric Dumazet)
- if we avoid the panic, though, we need to explicitly check the headroom
before the memcpy(), otherwise we'll have corrupted slabs on a running
kernel, after we warn
- use __skb_push() instead of skb_push(), as the headroom check is
already implemented here explicitly (Eric Dumazet)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Even if we send an IPv6 packet without options, MAX_HEADER might not be
enough to account for the additional headroom required by alignment of
hardware headers.
On a configuration without HYPERV_NET, WLAN, AX25, and with IPV6_TUNNEL,
sending short SCTP packets over IPv4 over L2TP over IPv6, we start with
100 bytes of allocated headroom in sctp_packet_transmit(), end up with 54
bytes after l2tp_xmit_skb(), and 14 bytes in ip6_finish_output2().
Those would be enough to append our 14 bytes header, but we're going to
align that to 16 bytes, and write 2 bytes out of the allocated slab in
neigh_hh_output().
KASan says:
[ 264.967848] ==================================================================
[ 264.967861] BUG: KASAN: slab-out-of-bounds in ip6_finish_output2+0x1aec/0x1c70
[ 264.967866] Write of size 16 at addr 000000006af1c7fe by task netperf/6201
[ 264.967870]
[ 264.967876] CPU: 0 PID: 6201 Comm: netperf Not tainted 4.20.0-rc4+ #1
[ 264.967881] Hardware name: IBM 2827 H43 400 (z/VM 6.4.0)
[ 264.967887] Call Trace:
[ 264.967896] ([<00000000001347d6>] show_stack+0x56/0xa0)
[ 264.967903] [<00000000017e379c>] dump_stack+0x23c/0x290
[ 264.967912] [<00000000007bc594>] print_address_description+0xf4/0x290
[ 264.967919] [<00000000007bc8fc>] kasan_report+0x13c/0x240
[ 264.967927] [<000000000162f5e4>] ip6_finish_output2+0x1aec/0x1c70
[ 264.967935] [<000000000163f890>] ip6_finish_output+0x430/0x7f0
[ 264.967943] [<000000000163fe44>] ip6_output+0x1f4/0x580
[ 264.967953] [<000000000163882a>] ip6_xmit+0xfea/0x1ce8
[ 264.967963] [<00000000017396e2>] inet6_csk_xmit+0x282/0x3f8
[ 264.968033] [<000003ff805fb0ba>] l2tp_xmit_skb+0xe02/0x13e0 [l2tp_core]
[ 264.968037] [<000003ff80631192>] l2tp_eth_dev_xmit+0xda/0x150 [l2tp_eth]
[ 264.968041] [<0000000001220020>] dev_hard_start_xmit+0x268/0x928
[ 264.968069] [<0000000001330e8e>] sch_direct_xmit+0x7ae/0x1350
[ 264.968071] [<000000000122359c>] __dev_queue_xmit+0x2b7c/0x3478
[ 264.968075] [<00000000013d2862>] ip_finish_output2+0xce2/0x11a0
[ 264.968078] [<00000000013d9b14>] ip_finish_output+0x56c/0x8c8
[ 264.968081] [<00000000013ddd1e>] ip_output+0x226/0x4c0
[ 264.968083] [<00000000013dbd6c>] __ip_queue_xmit+0x894/0x1938
[ 264.968100] [<000003ff80bc3a5c>] sctp_packet_transmit+0x29d4/0x3648 [sctp]
[ 264.968116] [<000003ff80b7bf68>] sctp_outq_flush_ctrl.constprop.5+0x8d0/0xe50 [sctp]
[ 264.968131] [<000003ff80b7c716>] sctp_outq_flush+0x22e/0x7d8 [sctp]
[ 264.968146] [<000003ff80b35c68>] sctp_cmd_interpreter.isra.16+0x530/0x6800 [sctp]
[ 264.968161] [<000003ff80b3410a>] sctp_do_sm+0x222/0x648 [sctp]
[ 264.968177] [<000003ff80bbddac>] sctp_primitive_ASSOCIATE+0xbc/0xf8 [sctp]
[ 264.968192] [<000003ff80b93328>] __sctp_connect+0x830/0xc20 [sctp]
[ 264.968208] [<000003ff80bb11ce>] sctp_inet_connect+0x2e6/0x378 [sctp]
[ 264.968212] [<0000000001197942>] __sys_connect+0x21a/0x450
[ 264.968215] [<000000000119aff8>] sys_socketcall+0x3d0/0xb08
[ 264.968218] [<000000000184ea7a>] system_call+0x2a2/0x2c0
[...]
Just like ip_finish_output2() does for IPv4, check that we have enough
headroom in ip6_xmit(), and reallocate it if we don't.
This issue is older than git history.
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_tso_should_defer() can return true in three different cases :
1) We are cwnd-limited
2) We are rwnd-limited
3) We are application limited.
Neal pointed out that my recent fix went too far, since
it assumed that if we were not in 1) case, we must be rwnd-limited
Fix this by properly populating the is_cwnd_limited and
is_rwnd_limited booleans.
After this change, we can finally move the silly check for FIN
flag only for the application-limited case.
The same move for EOR bit will be handled in net-next,
since commit 1c09f7d073 ("tcp: do not try to defer skbs
with eor mark (MSG_EOR)") is scheduled for linux-4.21
Tested by running 200 concurrent netperf -t TCP_RR -- -r 60000,100
and checking none of them was rwnd_limited in the chrono_stat
output from "ss -ti" command.
Fixes: 41727549de ("tcp: Do not underestimate rwnd_limited")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A couple of last-minute fixes.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull vhost/virtio fixes from Michael Tsirkin:
"A couple of last-minute fixes"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost/vsock: fix use-after-free in network stack callers
virtio/s390: fix race in ccw_io_helper()
virtio/s390: avoid race on vcdev->config
vhost/vsock: fix reset orphans race with close timeout
Pull crypto fixes from Herbert Xu:
- Disable the new crypto stats interface as it's still being changed
- Fix potential uses-after-free in cbc/cfb/pcbc.
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: user - Disable statistics interface
crypto: do not free algorithm before using
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Merge tag 'pci-v4.20-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fixes from Bjorn Helgaas:
"Revert ASPM change that caused a regression"
* tag 'pci-v4.20-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
Revert "PCI/ASPM: Do not initialize link state when aspm_disabled is set"
In 'seg6_output', stack variable 'struct flowi6 fl6' was missing
initialization.
Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'for-linus-20181207' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Let's try this again...
We're finally happy with the DM livelock issue, and it's also passed
overnight testing and the corruption regression test. The end result
is much nicer now too, which is great.
Outside of that fix, there's a pull request for NVMe with two small
fixes, and a regression fix for BFQ from this merge window. The BFQ
fix looks bigger than it is, it's 90% comment updates"
* tag 'for-linus-20181207' of git://git.kernel.dk/linux-block:
blk-mq: punt failed direct issue to dispatch list
nvmet-rdma: fix response use after free
nvme: validate controller state before rescheduling keep alive
block, bfq: fix decrement of num_active_groups
Pull i2c fixes from Wolfram Sang:
"A set of driver bugfixes for the I2C subsystem"
* 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: uniphier-f: fix violation of tLOW requirement for Fast-mode
i2c: uniphier: fix violation of tLOW requirement for Fast-mode
i2c: uniphier-f: fill TX-FIFO only in IRQ handler for repeated START
i2c: uniphier-f: fix timeout error after reading 8 bytes
i2c: scmi: Fix probe error on devices with an empty SMB0001 ACPI device node
i2c: axxia: properly handle master timeout
i2c: rcar: check bus state before reinitializing
i2c: nvidia-gpu: limit reads also for combined messages
i2c: nvidia-gpu: adhere to I2C fault codes
dmaengine fixes for v4.20-rc6
- Fixing imx-sdma handling of channel terminations, this involves
reverting two commits and implement async termination
- Fix cppi dma channel deletion from pending list on stop
- Fix FIFO size for dw controller in Intel Merrifield
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Merge tag 'dmaengine-fix-4.20-rc6' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fixes from Vinod Koul:
"Another pull request for dmaengine. We got bunch of fixes early this
week and all are tagged to stable. Hope this is last fix for this
cycle:
- Fix imx-sdma handling of channel terminations, this involves
reverting two commits and implement async termination
- Fix cppi dma channel deletion from pending list on stop
- Fix FIFO size for dw controller in Intel Merrifield"
* tag 'dmaengine-fix-4.20-rc6' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: dw: Fix FIFO size for Intel Merrifield
dmaengine: cppi41: delete channel from pending list when stop channel
dmaengine: imx-sdma: use GFP_NOWAIT for dma descriptor allocations
dmaengine: imx-sdma: implement channel termination via worker
Revert "dmaengine: imx-sdma: alloclate bd memory from dma pool"
Revert "dmaengine: imx-sdma: Use GFP_NOWAIT for dma allocations"
GNU linker's -z common-page-size's default value is based on the target
architecture. arch/x86/entry/vdso/Makefile sets it to the architecture
default, which is implicit and redundant. Drop it.
Fixes: 2aae950b21 ("x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu")
Reported-by: Dmitry Golovin <dima@golovin.in>
Reported-by: Bill Wendling <morbo@google.com>
Suggested-by: Dmitry Golovin <dima@golovin.in>
Suggested-by: Rui Ueyama <ruiu@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Fangrui Song <maskray@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181206191231.192355-1-ndesaulniers@google.com
Link: https://bugs.llvm.org/show_bug.cgi?id=38774
Link: https://github.com/ClangBuiltLinux/linux/issues/31
Since commit 3b8c9f1cdf ("arm64: IPI each CPU after invalidating the
I-cache for kernel mappings"), a call to flush_icache_range() will use
an IPI to cross-call other online CPUs so that any stale instructions
are flushed from their pipelines. This triggers a WARN during the
hibernation resume path, where flush_icache_range() is called with
interrupts disabled and is therefore prone to deadlock:
| Disabling non-boot CPUs ...
| CPU1: shutdown
| psci: CPU1 killed.
| CPU2: shutdown
| psci: CPU2 killed.
| CPU3: shutdown
| psci: CPU3 killed.
| WARNING: CPU: 0 PID: 1 at ../kernel/smp.c:416 smp_call_function_many+0xd4/0x350
| Modules linked in:
| CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.20.0-rc4 #1
Since all secondary CPUs have been taken offline prior to invalidating
the I-cache, there's actually no need for an IPI and we can simply call
__flush_icache_range() instead.
Cc: <stable@vger.kernel.org>
Fixes: 3b8c9f1cdf ("arm64: IPI each CPU after invalidating the I-cache for kernel mappings")
Reported-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Tested-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Pull NVMe fixes from Christoph.
* 'nvme-4.20' of git://git.infradead.org/nvme:
nvmet-rdma: fix response use after free
nvme: validate controller state before rescheduling keep alive
After the direct dispatch corruption fix, we permanently disallow direct
dispatch of non read/write requests. This works fine off the normal IO
path, as they will be retried like any other failed direct dispatch
request. But for the blk_insert_cloned_request() that only DM uses to
bypass the bottom level scheduler, we always first attempt direct
dispatch. For some types of requests, that's now a permanent failure,
and no amount of retrying will make that succeed. This results in a
livelock.
Instead of making special cases for what we can direct issue, and now
having to deal with DM solving the livelock while still retaining a BUSY
condition feedback loop, always just add a request that has been through
->queue_rq() to the hardware queue dispatch list. These are safe to use
as no merging can take place there. Additionally, if requests do have
prepped data from drivers, we aren't dependent on them not sharing space
in the request structure to safely add them to the IO scheduler lists.
This basically reverts ffe81d4532 and is based on a patch from Ming,
but with the list insert case covered as well.
Fixes: ffe81d4532 ("blk-mq: fix corruption with direct issue")
Cc: stable@vger.kernel.org
Suggested-by: Ming Lei <ming.lei@redhat.com>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
nvmet_rdma_release_rsp() may free the response before using it at error
flow.
Fixes: 8407879 ("nvmet-rdma: fix possible bogus dereference under heavy load")
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Delete operations are seeing NULL pointer references in call_timer_fn.
Tracking these back, the timer appears to be the keep alive timer.
nvme_keep_alive_work() which is tied to the timer that is cancelled
by nvme_stop_keep_alive(), simply starts the keep alive io but doesn't
wait for it's completion. So nvme_stop_keep_alive() only stops a timer
when it's pending. When a keep alive is in flight, there is no timer
running and the nvme_stop_keep_alive() will have no affect on the keep
alive io. Thus, if the io completes successfully, the keep alive timer
will be rescheduled. In the failure case, delete is called, the
controller state is changed, the nvme_stop_keep_alive() is called while
the io is outstanding, and the delete path continues on. The keep
alive happens to successfully complete before the delete paths mark it
as aborted as part of the queue termination, so the timer is restarted.
The delete paths then tear down the controller, and later on the timer
code fires and the timer entry is now corrupt.
Fix by validating the controller state before rescheduling the keep
alive. Testing with the fix has confirmed the condition above was hit.
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Since commit '2d29c9f89fcd ("block, bfq: improve asymmetric scenarios
detection")', if there are process groups with I/O requests waiting for
completion, then BFQ tags the scenario as 'asymmetric'. This detection
is needed for preserving service guarantees (for details, see comments
on the computation * of the variable asymmetric_scenario in the
function bfq_better_to_idle).
Unfortunately, commit '2d29c9f89fcd ("block, bfq: improve asymmetric
scenarios detection")' contains an error exactly in the updating of
the number of groups with I/O requests waiting for completion: if a
group has more than one descendant process, then the above number of
groups, which is renamed from num_active_groups to a more appropriate
num_groups_with_pending_reqs by this commit, may happen to be wrongly
decremented multiple times, namely every time one of the descendant
processes gets all its pending I/O requests completed.
A correct, complete solution should work as follows. Consider a group
that is inactive, i.e., that has no descendant process with pending
I/O inside BFQ queues. Then suppose that num_groups_with_pending_reqs
is still accounting for this group, because the group still has some
descendant process with some I/O request still in
flight. num_groups_with_pending_reqs should be decremented when the
in-flight request of the last descendant process is finally completed
(assuming that nothing else has changed for the group in the meantime,
in terms of composition of the group and active/inactive state of
child groups and processes). To accomplish this, an additional
pending-request counter must be added to entities, and must be
updated correctly.
To avoid this additional field and operations, this commit resorts to
the following tradeoff between simplicity and accuracy: for an
inactive group that is still counted in num_groups_with_pending_reqs,
this commit decrements num_groups_with_pending_reqs when the first
descendant process of the group remains with no request waiting for
completion.
This simplified scheme provides a fix to the unbalanced decrements
introduced by 2d29c9f89f. Since this error was also caused by lack
of comments on this non-trivial issue, this commit also adds related
comments.
Fixes: 2d29c9f89f ("block, bfq: improve asymmetric scenarios detection")
Reported-by: Steven Barrett <steven@liquorix.net>
Tested-by: Steven Barrett <steven@liquorix.net>
Tested-by: Lucjan Lucjanov <lucjan.lucjanov@gmail.com>
Reviewed-by: Federico Motta <federico@willer.it>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Here's a fix for a broken activation retry loop in the sirf driver.
Included are also two MAINTAINERS updates.
All have been in linux-next with no reported issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
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Merge tag 'gnss-4.20-rc6' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/gnss into char-misc-linus
Johan writes:
GNSS fixes for 4.20-rc6
Here's a fix for a broken activation retry loop in the sirf driver.
Included are also two MAINTAINERS updates.
All have been in linux-next with no reported issues.
Signed-off-by: Johan Hovold <johan@kernel.org>
* tag 'gnss-4.20-rc6' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/gnss:
MAINTAINERS: exclude gnss from SIRFPRIMA2 regex matching
MAINTAINERS: add gnss scm tree
gnss: sirf: fix activation retry handling
EBUSY is not handled by VFS, and will be passed to user-mode. This is not
correct as we need to wait for more credits.
This patch also fixes a bug where rsize or wsize is used uninitialized when
the call to server->ops->wait_mtu_credits() fails.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Since this user-space API is still undergoing significant changes,
this patch disables it for the current merge window.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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Merge tag 'drm-fixes-2018-12-07' of git://anongit.freedesktop.org/drm/drm
Pull drm fixes from Dave Airlie:
"There's a bit more in here than I'd like, and I'm hoping things calm
down when I'm out.
msm:
- a bunch of display fixes for the new DPU
- a couple of command submission fixes
omap:
- some DSI fixes
ast:
- driver unload crash fix
core:
- fix the lease uevent so userspace can distinguish it
amd:
- fix a bpc regression
- fix lru handling regression
- fixed firmware support for new GPUs
- power management fixes for vega20"
* tag 'drm-fixes-2018-12-07' of git://anongit.freedesktop.org/drm/drm: (37 commits)
drm/ast: Fix connector leak during driver unload
drm/amdgpu/vcn: Update vcn.cur_state during suspend
drm/amd/display: Fix overflow/truncation from strncpy.
drm/amd/powerplay: improve OD code robustness
drm/amdgpu: enlarge maximum waiting time of KIQ
drm/fb-helper: Fix typo in parameter description
drm/amd/powerplay: support SoftMin/Max setting for some specific DPM
drm/amd/powerplay: issue pre-display settings for display change event
drm/amd/powerplay: support new pptable upload on Vega20
drm/amdgpu/gmc8: always load MC firmware in the driver
drm/amdgpu/gmc8: update MC firmware for polaris
drm/amdgpu: update mc firmware image for polaris12 variants
drm/msm: Fix error return checking
drm/msm/dpu: Ignore alpha for XBGR8888 format
drm/msm: dpu: Fix "WARNING: invalid free of devm_ allocated data"
drm/msm/hdmi: Drop pointless static qualifier in msm_hdmi_bind()
drm/msm: Move fence put to where failure occurs
drm/msm: dpu: Don't set legacy plane->crtc pointer
drm/msm/gpu: Don't map command buffers with nr_relocs equal to 0
drm/msm/hdmi: Enable HPD after HDMI IRQ is set up
...
Highlights include:
Stable fixes:
- Fix a page leak when using RPCSEC_GSS/krb5p to encrypt data.
Bugfixes:
- Fix a regression that causes the RPC receive code to hang
- Fix call_connect_status() so that it handles tasks that got transmitted
while queued waiting for the socket lock.
- Fix a memory leak in call_encode()
- Fix several other connect races.
- Fix receive code error handling.
- Use the discard iterator rather than MSG_TRUNC for compatibility with
AF_UNIX/AF_LOCAL sockets.
- nfs: don't dirty kernel pages read by direct-io
- pnfs/Flexfiles fix to enforce per-mirror stateid only for NFSv4 data
servers
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Merge tag 'nfs-for-4.20-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"This is mainly fallout from the updates to the SUNRPC code that is
being triggered from less common combinations of NFS mount options.
Highlights include:
Stable fixes:
- Fix a page leak when using RPCSEC_GSS/krb5p to encrypt data.
Bugfixes:
- Fix a regression that causes the RPC receive code to hang
- Fix call_connect_status() so that it handles tasks that got
transmitted while queued waiting for the socket lock.
- Fix a memory leak in call_encode()
- Fix several other connect races.
- Fix receive code error handling.
- Use the discard iterator rather than MSG_TRUNC for compatibility
with AF_UNIX/AF_LOCAL sockets.
- nfs: don't dirty kernel pages read by direct-io
- pnfs/Flexfiles fix to enforce per-mirror stateid only for NFSv4
data servers"
* tag 'nfs-for-4.20-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
SUNRPC: Don't force a redundant disconnection in xs_read_stream()
SUNRPC: Fix up socket polling
SUNRPC: Use the discard iterator rather than MSG_TRUNC
SUNRPC: Treat EFAULT as a truncated message in xs_read_stream_request()
SUNRPC: Fix up handling of the XDRBUF_SPARSE_PAGES flag
SUNRPC: Fix RPC receive hangs
SUNRPC: Fix a potential race in xprt_connect()
SUNRPC: Fix a memory leak in call_encode()
SUNRPC: Fix leak of krb5p encode pages
SUNRPC: call_connect_status() must handle tasks that got transmitted
nfs: don't dirty kernel pages read by direct-io
flexfiles: enforce per-mirror stateid only for v4 DSes
Pull ARM spectre fix from Russell King:
"Exynos folk noticed that CPU hotplug wasn't working with their kernel
configuration, and have tested this as fixing the problem"
* 'spectre' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: ensure that processor vtables is not lost after boot
Pull ARM fixes from Russell King:
"Some small fixes that have been accumulated:
- Chris Cole noticed that in a SMP environment, the DMA cache
coherence handling can produce undesirable results in a corner
case
- Propagate that fix for ARMv7M as well
- Fix a false positive with source fortification
- Fix an uninitialised return that Nathan Jones spotted"
* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8816/1: dma-mapping: fix potential uninitialized return
ARM: 8815/1: V7M: align v7m_dma_inv_range() with v7 counterpart
ARM: 8814/1: mm: improve/fix ARM v7_dma_inv_range() unaligned address handling
ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE
Currently, the clock duty is set as tLOW/tHIGH = 1/1. For Fast-mode,
tLOW is set to 1.25 us while the I2C spec requires tLOW >= 1.3 us.
tLOW/tHIGH = 5/4 would meet both Standard-mode and Fast-mode:
Standard-mode: tLOW = 5.56 us, tHIGH = 4.44 us
Fast-mode: tLOW = 1.39 us, tHIGH = 1.11 us
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently, the clock duty is set as tLOW/tHIGH = 1/1. For Fast-mode,
tLOW is set to 1.25 us while the I2C spec requires tLOW >= 1.3 us.
tLOW/tHIGH = 5/4 would meet both Standard-mode and Fast-mode:
Standard-mode: tLOW = 5.56 us, tHIGH = 4.44 us
Fast-mode: tLOW = 1.39 us, tHIGH = 1.11 us
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
- For a repeated START condition, this controller starts data transfer
immediately after the slave address is written to the TX-FIFO.
- Once the TX-FIFO empty interrupt is asserted, the controller makes
a pause even if additional data are written to the TX-FIFO.
Given those circumstances, the data after a repeated START may not be
transferred if the interrupt is asserted while the TX-FIFO is being
filled up. A more reliable way is to append TX data only in the
interrupt handler.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I was totally screwed up in commit eaba68785c ("i2c: uniphier-f:
fix race condition when IRQ is cleared"). Since that commit, if the
number of read bytes is multiple of the FIFO size (8, 16, 24... bytes),
the STOP condition could be issued twice, depending on the timing.
If this happens, the controller will go wrong, resulting in the timeout
error.
It was more than 3 years ago when I wrote this driver, so my memory
about this hardware was vague. Please let me correct the description
in the commit log of eaba68785c.
Clearing the IRQ status on exiting the IRQ handler is absolutely
fine. This controller makes a pause while any IRQ status is asserted.
If the IRQ status is cleared first, the hardware may start the next
transaction before the IRQ handler finishes what it supposed to do.
This partially reverts the bad commit with clear comments so that I
will never repeat this mistake.
I also investigated what is happening at the last moment of the read
mode. The UNIPHIER_FI2C_INT_RF interrupt is asserted a bit earlier
(by half a period of the clock cycle) than UNIPHIER_FI2C_INT_RB.
I consulted a hardware engineer, and I got the following information:
UNIPHIER_FI2C_INT_RF
asserted at the falling edge of SCL at the 8th bit.
UNIPHIER_FI2C_INT_RB
asserted at the rising edge of SCL at the 9th (ACK) bit.
In order to avoid calling uniphier_fi2c_stop() twice, check the latter
interrupt. I also commented this because it is obscure hardware internal.
Fixes: eaba68785c ("i2c: uniphier-f: fix race condition when IRQ is cleared")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
