- 05 Feb, 2015 1 commit
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NeilBrown authored
This makes it safe to inspect the struct while holding only the spinlock. Signed-off-by: NeilBrown <neilb@suse.de>
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- 03 Feb, 2015 14 commits
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NeilBrown authored
->pers is already protected by ->reconfig_mutex, and cannot possibly change when there are threads running or outstanding IO. However there are some places where we access ->pers not in a thread or IO context, and where ->reconfig_mutex is unnecessarily heavy-weight: level_show and md_seq_show(). So protect all changes, and those accesses, with ->lock. This is a step toward taking those accesses out from under reconfig_mutex. [Fixed missing "mddev->pers" -> "pers" conversion, thanks to Dan Carpenter <dan.carpenter@oracle.com>] Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
Gather all the changes that can happen atomically and might be relevant to other code into one place. This will make it easier to refine the locking. Note that this puts quite a few things between mddev_detach() and ->free(). Enabling this was the point of some recent patches. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
Now that the ->stop function only frees the private data, rename is accordingly. Also pass in the private pointer as an arg rather than using mddev->private. This flexibility will be useful in level_store(). Finally, don't clear ->private. It doesn't make sense to clear it seeing that isn't what we free, and it is no longer necessary to clear ->private (it was some time ago before ->to_remove was introduced). Setting ->to_remove in ->free() is a bit of a wart, but not a big problem at the moment. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
Each md personality has a 'stop' operation which does two things: 1/ it finalizes some aspects of the array to ensure nothing is accessing the ->private data 2/ it frees the ->private data. All the steps in '1' can apply to all arrays and so can be performed in common code. This is useful as in the case where we change the personality which manages an array (in level_store()), it would be helpful to do step 1 early, and step 2 later. So split the 'step 1' functionality out into a new mddev_detach(). Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
The use of 'rcu' to protect accesses to ->private_data so that the ->private_data could be updated predates the introduction of mddev_suspend/mddev_resume. These are a cleaner mechanism for providing stability while swapping in a new ->private data - it is used by level_store() to support changing of raid levels. So get rid of the RCU stuff and just use mddev_suspend, mddev_resume. As these function call ->quiesce(), we add an empty function for linear just like for raid0. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
There is no locking around calls to merge_bvec_fn(), so it is possible that calls which coincide with a level (or personality) change could go wrong. So create a central dispatch point for these functions and use rcu_read_lock(). If the array is suspended, reject any merge that can be rejected. If not, we know it is safe to call the function. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
There is currently no locking around calls to the 'congested' bdi function. If called at an awkward time while an array is being converted from one level (or personality) to another, there is a tiny chance of running code in an unreferenced module etc. So add a 'congested' function to the md_personality operations structure, and call it with appropriate locking from a central 'mddev_congested'. When the array personality is changing the array will be 'suspended' so no IO is processed. If mddev_congested detects this, it simply reports that the array is congested, which is a safe guess. As mddev_suspend calls synchronize_rcu(), mddev_congested can avoid races by included the whole call inside an rcu_read_lock() region. This require that the congested functions for all subordinate devices can be run under rcu_lock. Fortunately this is the case. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
This lock is used for (slightly) more than helping with writing superblocks, and it will soon be extended further. So the name is inappropriate. Also, the _irq variant hasn't been needed since 2.6.37 as it is never taking from interrupt or bh context. So: -rename write_lock to lock -document what it protects -remove _irq ... except in md_flush_request() as there is no wait_event_lock() (with no _irq). This can be cleaned up after appropriate changes to wait.h. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
That last condition is unclear and over cautious. There are two related issues here. If a partial write is destined for a missing device, then either RMW or RCW can work. We must read all the available block. Only then can the missing blocks be calculated, and then the parity update performed. If RMW is not an option, then there is a complication even without partial writes. If we would need to read a missing device to perform the reconstruction, then we must first read every block so the missing device data can be computed. This is the case for RAID6 (Which currently does not support RMW) and for times when we don't trust the parity (after a crash) and so are in the process of resyncing it. So make these two cases more clear and separate, and perform the relevant tests more thoroughly. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
Both the last two cases are only relevant if something has failed and something needs to be written (but not over-written), and if it is OK to pre-read blocks at this point. So factor out those tests and explain them. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
Some of the conditions in need_this_block have very straight forward motivation. Separate those out and document them. Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
fetch_block() has a very large and hard to read 'if' condition. Separate it into its own function so that it can be made more readable. Signed-off-by: NeilBrown <neilb@suse.de>
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Jes Sorensen authored
67f45548 introduced a call to md_wakeup_thread() when adding to the delayed_list. However the md thread is woken up unconditionally just below. Remove the unnecessary wakeup call. Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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Jan Beulich authored
Just like for AVX2 (which simply needs an #if -> #ifdef conversion), SSSE3 assembler support should be checked for before using it. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Jim Kukunas <james.t.kukunas@linux.intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NeilBrown <neilb@suse.de>
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- 02 Feb, 2015 2 commits
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NeilBrown authored
commit 8eb23b9f sched: Debug nested sleeps causes false-positive warnings in RAID5 code. This annotation removes them and adds a comment explaining why there is no real problem. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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NeilBrown authored
If a non-page-aligned write is destined for a device which is missing/faulty, we can deadlock. As the target device is missing, a read-modify-write cycle is not possible. As the write is not for a full-page, a recontruct-write cycle is not possible. This should be handled by logic in fetch_block() which notices there is a non-R5_OVERWRITE write to a missing device, and so loads all blocks. However since commit 67f45548, that code requires STRIPE_PREREAD_ACTIVE before it will active, and those circumstances never set STRIPE_PREREAD_ACTIVE. So: in handle_stripe_dirtying, if neither rmw or rcw was possible, set STRIPE_DELAYED, which will cause STRIPE_PREREAD_ACTIVE be set after a suitable delay. Fixes: 67f45548 Cc: stable@vger.kernel.org (v3.16+) Reported-by: Mikulas Patocka <mpatocka@redhat.com> Tested-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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- 27 Jan, 2015 23 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) Don't OOPS on socket AIO, from Christoph Hellwig. 2) Scheduled scans should be aborted upon RFKILL, from Emmanuel Grumbach. 3) Fix sleep in atomic context in kvaser_usb, from Ahmed S Darwish. 4) Fix RCU locking across copy_to_user() in bpf code, from Alexei Starovoitov. 5) Lots of crash, memory leak, short TX packet et al bug fixes in sh_eth from Ben Hutchings. 6) Fix memory corruption in SCTP wrt. INIT collitions, from Daniel Borkmann. 7) Fix return value logic for poll handlers in netxen, enic, and bnx2x. From Eric Dumazet and Govindarajulu Varadarajan. 8) Header length calculation fix in mac80211 from Fred Chou. 9) mv643xx_eth doesn't handle highmem correctly in non-TSO code paths. From Ezequiel Garcia. 10) udp_diag has bogus logic in it's hash chain skipping, copy same fix tcp diag used. From Herbert Xu. 11) amd-xgbe programs wrong rx flow control register, from Thomas Lendacky. 12) Fix race leading to use after free in ping receive path, from Subash Abhinov Kasiviswanathan. 13) Cache redirect routes otherwise we can get a heavy backlog of rcu jobs liberating DST_NOCACHE entries. From Hannes Frederic Sowa. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (48 commits) net: don't OOPS on socket aio stmmac: prevent probe drivers to crash kernel bnx2x: fix napi poll return value for repoll ipv6: replacing a rt6_info needs to purge possible propagated rt6_infos too sh_eth: Fix DMA-API usage for RX buffers sh_eth: Check for DMA mapping errors on transmit sh_eth: Ensure DMA engines are stopped before freeing buffers sh_eth: Remove RX overflow log messages ping: Fix race in free in receive path udp_diag: Fix socket skipping within chain can: kvaser_usb: Fix state handling upon BUS_ERROR events can: kvaser_usb: Retry the first bulk transfer on -ETIMEDOUT can: kvaser_usb: Send correct context to URB completion can: kvaser_usb: Do not sleep in atomic context ipv4: try to cache dst_entries which would cause a redirect samples: bpf: relax test_maps check bpf: rcu lock must not be held when calling copy_to_user() net: sctp: fix slab corruption from use after free on INIT collisions net: mv643xx_eth: Fix highmem support in non-TSO egress path sh_eth: Fix serialisation of interrupt disable with interrupt & NAPI handlers ...
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Christoph Hellwig authored
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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Andy Shevchenko authored
In the case when alloc_netdev fails we return NULL to a caller. But there is no check for NULL in the probe drivers. This patch changes NULL to an error pointer. The function description is amended to reflect what we may get returned. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: "Two powerpc fixes" * tag 'powerpc-3.19-5' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/powernv: Restore LPCR with LPCR_PECE1 cleared powerpc/xmon: Fix another endiannes issue in RTAS call from xmon
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git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linuxLinus Torvalds authored
Pull one more module fix from Rusty Russell: "SCSI was using module_refcount() to figure out when the module was unloading: this broke with new atomic refcounting. The code is still suspicious, but this solves the WARN_ON()" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: scsi: always increment reference count
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Govindarajulu Varadarajan authored
With the commit d75b1ade ("net: less interrupt masking in NAPI") napi repoll is done only when work_done == budget. When in busy_poll is we return 0 in napi_poll. We should return budget. Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsecDavid S. Miller authored
Steffen Klassert says: ==================== ipsec 2015-01-26 Just two small fixes for _decode_session6() where we might decode to wrong header information in some rare situations. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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Hannes Frederic Sowa authored
Lubomir Rintel reported that during replacing a route the interface reference counter isn't correctly decremented. To quote bug <https://bugzilla.kernel.org/show_bug.cgi?id=91941>: | [root@rhel7-5 lkundrak]# sh -x lal | + ip link add dev0 type dummy | + ip link set dev0 up | + ip link add dev1 type dummy | + ip link set dev1 up | + ip addr add 2001:db8:8086::2/64 dev dev0 | + ip route add 2001:db8:8086::/48 dev dev0 proto static metric 20 | + ip route add 2001:db8:8088::/48 dev dev1 proto static metric 10 | + ip route replace 2001:db8:8086::/48 dev dev1 proto static metric 20 | + ip link del dev0 type dummy | Message from syslogd@rhel7-5 at Jan 23 10:54:41 ... | kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2 | | Message from syslogd@rhel7-5 at Jan 23 10:54:51 ... | kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2 During replacement of a rt6_info we must walk all parent nodes and check if the to be replaced rt6_info got propagated. If so, replace it with an alive one. Fixes: 4a287eba ("IPv6 routing, NLM_F_* flag support: REPLACE and EXCL flags support, warn about missing CREATE flag") Reported-by: Lubomir Rintel <lkundrak@v3.sk> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Tested-by: Lubomir Rintel <lkundrak@v3.sk> Signed-off-by: David S. Miller <davem@davemloft.net>
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David S. Miller authored
Ben Hutchings says: ==================== Fixes for sh_eth #3 I'm continuing review and testing of Ethernet support on the R-Car H2 chip. This series fixes the last of the more serious issues I've found. These are not tested on any of the other supported chips. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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Ben Hutchings authored
- Use the return value of dma_map_single(), rather than calling virt_to_page() separately - Check for mapping failue - Call dma_unmap_single() rather than dma_sync_single_for_cpu() Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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Ben Hutchings authored
dma_map_single() may fail if an IOMMU or swiotlb is in use, so we need to check for this. Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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Ben Hutchings authored
Currently we try to clear EDRRR and EDTRR and immediately continue to free buffers. This is unsafe because: - In general, register writes are not serialised with DMA, so we still have to wait for DMA to complete somehow - The R8A7790 (R-Car H2) manual states that the TX running flag cannot be cleared by writing to EDTRR - The same manual states that clearing the RX running flag only stops RX DMA at the next packet boundary I applied this patch to the driver to detect DMA writes to freed buffers: > --- a/drivers/net/ethernet/renesas/sh_eth.c > +++ b/drivers/net/ethernet/renesas/sh_eth.c > @@ -1098,7 +1098,14 @@ static void sh_eth_ring_free(struct net_device *ndev) > /* Free Rx skb ringbuffer */ > if (mdp->rx_skbuff) { > for (i = 0; i < mdp->num_rx_ring; i++) > + memcpy(mdp->rx_skbuff[i]->data, > + "Hello, world", 12); > + msleep(100); > + for (i = 0; i < mdp->num_rx_ring; i++) { > + WARN_ON(memcmp(mdp->rx_skbuff[i]->data, > + "Hello, world", 12)); > dev_kfree_skb(mdp->rx_skbuff[i]); > + } > } > kfree(mdp->rx_skbuff); > mdp->rx_skbuff = NULL; then ran the loop: while ethtool -G eth0 rx 128 ; ethtool -G eth0 rx 64; do echo -n .; done and 'ping -f' toward the sh_eth port from another machine. The warning fired several times a minute. To fix these issues: - Deactivate all TX descriptors rather than writing to EDTRR - As there seems to be no way of telling when RX DMA is stopped, perform a soft reset to ensure that both DMA enginess are stopped - To reduce the possibility of the reset truncating a transmitted frame, disable egress and wait a reasonable time to reach a packet boundary before resetting - Update statistics before resetting (The 'reasonable time' does not allow for CS/CD in half-duplex mode, but half-duplex no longer seems reasonable!) Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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Ben Hutchings authored
If RX traffic is overflowing the FIFO or DMA ring, logging every time this happens just makes things worse. These errors are visible in the statistics anyway. Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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David S. Miller authored
Merge tag 'linux-can-fixes-for-3.19-20150127' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can Marc Kleine-Budde says: ==================== pull-request: can 2015-01-27 this is another pull request for net/master which consists of 4 patches. All 4 patches are contributed by Ahmed S. Darwish, he fixes more problems in the kvaser_usb driver. David, please merge net/master to net-next/master, as we have more kvaser_usb patches in the queue, that target net-next. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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subashab@codeaurora.org authored
An exception is seen in ICMP ping receive path where the skb destructor sock_rfree() tries to access a freed socket. This happens because ping_rcv() releases socket reference with sock_put() and this internally frees up the socket. Later icmp_rcv() will try to free the skb and as part of this, skb destructor is called and which leads to a kernel panic as the socket is freed already in ping_rcv(). -->|exception -007|sk_mem_uncharge -007|sock_rfree -008|skb_release_head_state -009|skb_release_all -009|__kfree_skb -010|kfree_skb -011|icmp_rcv -012|ip_local_deliver_finish Fix this incorrect free by cloning this skb and processing this cloned skb instead. This patch was suggested by Eric Dumazet Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Herbert Xu authored
While working on rhashtable walking I noticed that the UDP diag dumping code is buggy. In particular, the socket skipping within a chain never happens, even though we record the number of sockets that should be skipped. As this code was supposedly copied from TCP, this patch does what TCP does and resets num before we walk a chain. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Ahmed S. Darwish authored
While being in an ERROR_WARNING state, and receiving further bus error events with error counters still in the ERROR_WARNING range of 97-127 inclusive, the state handling code erroneously reverts back to ERROR_ACTIVE. Per the CAN standard, only revert to ERROR_ACTIVE when the error counters are less than 96. Moreover, in certain Kvaser models, the BUS_ERROR flag is always set along with undefined bits in the M16C status register. Thus use bitwise operators instead of full equality for checking that register against bus errors. Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com> Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Ahmed S. Darwish authored
On some x86 laptops, plugging a Kvaser device again after an unplug makes the firmware always ignore the very first command. For such a case, provide some room for retries instead of completely exiting the driver init code. Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com> Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Ahmed S. Darwish authored
Send expected argument to the URB completion hander: a CAN netdevice instead of the network interface private context `kvaser_usb_net_priv'. This was discovered by having some garbage in the kernel log in place of the netdevice names: can0 and can1. Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com> Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Ahmed S. Darwish authored
Upon receiving a hardware event with the BUS_RESET flag set, the driver kills all of its anchored URBs and resets all of its transmit URB contexts. Unfortunately it does so under the context of URB completion handler `kvaser_usb_read_bulk_callback()', which is often called in an atomic context. While the device is flooded with many received error packets, usb_kill_urb() typically sleeps/reschedules till the transfer request of each killed URB in question completes, leading to the sleep in atomic bug. [3] In v2 submission of the original driver patch [1], it was stated that the URBs kill and tx contexts reset was needed since we don't receive any tx acknowledgments later and thus such resources will be locked down forever. Fortunately this is no longer needed since an earlier bugfix in this patch series is now applied: all tx URB contexts are reset upon CAN channel close. [2] Moreover, a BUS_RESET is now treated _exactly_ like a BUS_OFF event, which is the recommended handling method advised by the device manufacturer. [1] http://article.gmane.org/gmane.linux.network/239442 http://www.webcitation.org/6Vr2yagAQ [2] can: kvaser_usb: Reset all URB tx contexts upon channel close 889b77f7 [3] Stacktrace: <IRQ> [<ffffffff8158de87>] dump_stack+0x45/0x57 [<ffffffff8158b60c>] __schedule_bug+0x41/0x4f [<ffffffff815904b1>] __schedule+0x5f1/0x700 [<ffffffff8159360a>] ? _raw_spin_unlock_irqrestore+0xa/0x10 [<ffffffff81590684>] schedule+0x24/0x70 [<ffffffff8147d0a5>] usb_kill_urb+0x65/0xa0 [<ffffffff81077970>] ? prepare_to_wait_event+0x110/0x110 [<ffffffff8147d7d8>] usb_kill_anchored_urbs+0x48/0x80 [<ffffffffa01f4028>] kvaser_usb_unlink_tx_urbs+0x18/0x50 [kvaser_usb] [<ffffffffa01f45d0>] kvaser_usb_rx_error+0xc0/0x400 [kvaser_usb] [<ffffffff8108b14a>] ? vprintk_default+0x1a/0x20 [<ffffffffa01f5241>] kvaser_usb_read_bulk_callback+0x4c1/0x5f0 [kvaser_usb] [<ffffffff8147a73e>] __usb_hcd_giveback_urb+0x5e/0xc0 [<ffffffff8147a8a1>] usb_hcd_giveback_urb+0x41/0x110 [<ffffffffa0008748>] finish_urb+0x98/0x180 [ohci_hcd] [<ffffffff810cd1a7>] ? acct_account_cputime+0x17/0x20 [<ffffffff81069f65>] ? local_clock+0x15/0x30 [<ffffffffa000a36b>] ohci_work+0x1fb/0x5a0 [ohci_hcd] [<ffffffff814fbb31>] ? process_backlog+0xb1/0x130 [<ffffffffa000cd5b>] ohci_irq+0xeb/0x270 [ohci_hcd] [<ffffffff81479fc1>] usb_hcd_irq+0x21/0x30 [<ffffffff8108bfd3>] handle_irq_event_percpu+0x43/0x120 [<ffffffff8108c0ed>] handle_irq_event+0x3d/0x60 [<ffffffff8108ec84>] handle_fasteoi_irq+0x74/0x110 [<ffffffff81004dfd>] handle_irq+0x1d/0x30 [<ffffffff81004727>] do_IRQ+0x57/0x100 [<ffffffff8159482a>] common_interrupt+0x6a/0x6a Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com> Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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David S. Miller authored
Merge tag 'mac80211-for-davem-2015-01-23' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 Another set of last-minute fixes: * fix station double-removal when suspending while associating * fix the HT (802.11n) header length calculation * fix the CCK radiotap flag used for monitoring, a pretty old regression but a simple one-liner * fix per-station group-key handling Signed-off-by: David S. Miller <davem@davemloft.net>
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Hannes Frederic Sowa authored
Not caching dst_entries which cause redirects could be exploited by hosts on the same subnet, causing a severe DoS attack. This effect aggravated since commit f8864972 ("ipv4: fix dst race in sk_dst_get()"). Lookups causing redirects will be allocated with DST_NOCACHE set which will force dst_release to free them via RCU. Unfortunately waiting for RCU grace period just takes too long, we can end up with >1M dst_entries waiting to be released and the system will run OOM. rcuos threads cannot catch up under high softirq load. Attaching the flag to emit a redirect later on to the specific skb allows us to cache those dst_entries thus reducing the pressure on allocation and deallocation. This issue was discovered by Marcelo Leitner. Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: Marcelo Leitner <mleitner@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
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David S. Miller authored
Alexei Starovoitov says: ==================== bpf: fix two bugs Michael Holzheu caught two issues (in bpf syscall and in the test). Fix them. Details in corresponding patches. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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