- 19 Sep, 2012 6 commits
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Johannes Berg authored
commit 4fc79db1 upstream. If the device is not started, we can't read its SRAM and attempting to do so will cause issues. Protect the debugfs read. Signed-off-by:
Johannes Berg <johannes.berg@intel.com> Signed-off-by:
John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2: - Adjust context - Pass iwl_shared not iwl_priv pointer to iwl_is_ready_rf()] Signed-off-by:
Ben Hutchings <ben@decadent.org.uk>
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Johannes Berg authored
commit 94543a8d upstream. iwl_dbgfs_fh_reg_read() can cause crashes and/or BUG_ON in slub because the ifdefs are wrong, the code in iwl_dump_fh() should use DEBUGFS, not DEBUG to protect the buffer writing code. Also, while at it, clean up the arguments to the function, some code and make it generally safer. Reported-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
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Arnaud Patard (Rtp) authored
commit 58569aee upstream. The mv643xx ethernet controller limits the packet size for the TX checksum offloading. This patch sets this limits for Kirkwood and Dove which have smaller limits that the default. As a side note, this patch is an updated version of a patch sent some years ago: http://lists.infradead.org/pipermail/linux-arm-kernel/2010-June/017320.html which seems to have been lost. Signed-off-by:
Arnaud Patard <arnaud.patard@rtp-net.org> Signed-off-by:
Jason Cooper <jason@lakedaemon.net> [bwh: Backported to 3.2: adjust for the extra two parameters of orion_ge0{0,1}_init()] Signed-off-by:
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Jon Hunter authored
commit 54f32a35 upstream. Calling the dmtimer function omap_dm_timer_set_source() fails if following a call to pm_runtime_put() to disable the timer. For example the following sequence would fail to set the parent clock ... omap_dm_timer_stop(gptimer); omap_dm_timer_set_source(gptimer, OMAP_TIMER_SRC_32_KHZ); The following error message would be seen ... omap_dm_timer_set_source: failed to set timer_32k_ck as parent The problem is that, by design, pm_runtime_put() simply decrements the usage count and returns before the timer has actually been disabled. Therefore, setting the parent clock failed because the timer was still active when the trying to set the parent clock. Setting a parent clock will fail if the clock you are setting the parent of has a non-zero usage count. To ensure that this does not fail use pm_runtime_put_sync() when disabling the timer. Note that this will not be seen on OMAP1 devices, because these devices do not use the clock framework for dmtimers. Signed-off-by:
Jon Hunter <jon-hunter@ti.com> Acked-by:
Kevin Hilman <khilman@ti.com> Signed-off-by:
Tony Lindgren <tony@atomide.com> Signed-off-by:
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Heiko Stuebner authored
commit b01858c7 upstream. Commit d670ac01 (ARM: SAMSUNG: DMA Cleanup as per sparse) changed the prototype of the s3c2410_dma_* functions to use the enum dma_ch instead of an generic unsigned int. In the s3c24xx dma.c s3c2410_dma_enqueue seems to have been forgotten, the other functions there were changed correctly. Signed-off-by:
Heiko Stuebner <heiko@sntech.de> Signed-off-by:
Kukjin Kim <kgene.kim@samsung.com> Signed-off-by:
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Mel Gorman authored
commit bba3d8c3 upstream. The following build error occured during a parisc build with swap-over-NFS patches applied. net/core/sock.c:274:36: error: initializer element is not constant net/core/sock.c:274:36: error: (near initialization for 'memalloc_socks') net/core/sock.c:274:36: error: initializer element is not constant Dave Anglin says: > Here is the line in sock.i: > > struct static_key memalloc_socks = ((struct static_key) { .enabled = > ((atomic_t) { (0) }) }); The above line contains two compound literals. It also uses a designated initializer to initialize the field enabled. A compound literal is not a constant expression. The location of the above statement isn't fully clear, but if a compound literal occurs outside the body of a function, the initializer list must consist of constant expressions. Reported-by:
Fengguang Wu <fengguang.wu@intel.com> Signed-off-by:
Mel Gorman <mgorman@suse.de> Signed-off-by:
James Bottomley <JBottomley@Parallels.com> Signed-off-by:
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- 12 Sep, 2012 34 commits
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Ben Hutchings authored
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Satoru Moriya authored
commit fe35004f upstream. Sometimes we'd like to avoid swapping out anonymous memory. In particular, avoid swapping out pages of important process or process groups while there is a reasonable amount of pagecache on RAM so that we can satisfy our customers' requirements. OTOH, we can control how aggressive the kernel will swap memory pages with /proc/sys/vm/swappiness for global and /sys/fs/cgroup/memory/memory.swappiness for each memcg. But with current reclaim implementation, the kernel may swap out even if we set swappiness=0 and there is pagecache in RAM. This patch changes the behavior with swappiness==0. If we set swappiness==0, the kernel does not swap out completely (for global reclaim until the amount of free pages and filebacked pages in a zone has been reduced to something very very small (nr_free + nr_filebacked < high watermark)). Signed-off-by:
Satoru Moriya <satoru.moriya@hds.com> Acked-by:
Minchan Kim <minchan@kernel.org> Reviewed-by:
Rik van Riel <riel@redhat.com> Acked-by:
Jerome Marchand <jmarchan@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: - Adjust context - vmscan_swappiness() does not have a zone parameter] Signed-off-by:
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Phillip Lougher authored
commit cc37f75a upstream. A Squashfs filesystem containing nothing but an empty directory, although unusual and ultimately pointless, is still valid. The directory_table >= next_table sanity check rejects these filesystems as invalid because the directory_table is empty and equal to next_table. Signed-off-by:
Phillip Lougher <phillip@squashfs.org.uk> Signed-off-by:
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AceLan Kao authored
commit 3766054f upstream. There are some new video switch keys that used by newer machines. 0xA0 - SDSP HDMI only 0xA1 - SDSP LCD + HDMI 0xA2 - SDSP CRT + HDMI 0xA3 - SDSP TV + HDMI But in Linux, there is no suitable userspace application to handle this, so, mapping them all to KEY_SWITCHVIDEOMODE. Signed-off-by:
AceLan Kao <acelan.kao@canonical.com> Signed-off-by:
Matthew Garrett <mjg@redhat.com> Signed-off-by:
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Trond Myklebust authored
Fix the following Oops in 3.5.1: BUG: unable to handle kernel NULL pointer dereference at 0000000000000038 IP: [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs] PGD 337c63067 PUD 0 Oops: 0000 [#1] SMP CPU 5 Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys Pid: 30431, comm: java Not tainted 3.5.1-2-default #1 Supermicro X8DTT/X8DTT RIP: 0010:[<ffffffffa03789cd>] [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs] RSP: 0018:ffff8801b418bd38 EFLAGS: 00010292 RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020 RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00 RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00 R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0 FS: 00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600) Stack: ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000 ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0 ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000 Call Trace: [<ffffffff8116a9c0>] lookup_dcache+0x80/0xe0 [<ffffffff8116aa43>] __lookup_hash+0x23/0x90 [<ffffffff8116b4a5>] lookup_one_len+0xc5/0x100 [<ffffffffa03869a3>] nfs_sillyrename+0xe3/0x210 [nfs] [<ffffffff8116cadf>] vfs_unlink.part.25+0x7f/0xe0 [<ffffffff8116f22c>] do_unlinkat+0x1ac/0x1d0 [<ffffffff815717b9>] system_call_fastpath+0x16/0x1b [<00002b5348b5f527>] 0x2b5348b5f526 Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30 <f6> 46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89 RIP [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs] RSP <ffff8801b418bd38> CR2: 0000000000000038 ---[ end trace 845113ed191985dd ]--- This Oops affects 3.5 kernels and older, and is due to lookup_one_len() calling down to the dentry revalidation code with a NULL pointer to struct nameidata. It is fixed upstream by commit 0b728e19 (stop passing nameidata * to ->d_revalidate()) Reported-by:
Richard Ems <richard.ems@cape-horn-eng.com> Signed-off-by:
Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by:
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Christopher Brannon authored
commit 4ea418b8 upstream. A local static variable was declared as a pointer to a string constant. We're assigning to the underlying memory, so it needs to be an array instead. Signed-off-by:
Christopher Brannon <chris@the-brannons.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
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Jason Wessel authored
commit 38f8eefc upstream. kdb <-> kgdb transitioning does not work properly with this UART driver because the get character routine loops indefinitely as opposed to returning NO_POLL_CHAR per the expectation of the KDB I/O driver API. The symptom is a kernel hang when trying to switch debug modes. Cc: Alan Cox <alan@linux.intel.com> Signed-off-by:
Jason Wessel <jason.wessel@windriver.com> Signed-off-by:
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Lionel Vaux authored
commit 76c9d8fe upstream. Add yet another device to the list of Cypress barcode scanners needing the CP_RDESC_SWAPPED_MIN_MAX quirk. Signed-off-by:
Lionel Vaux (iouri) <lionel.vaux@free.fr> Signed-off-by:
Jiri Kosina <jkosina@suse.cz> Signed-off-by:
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Asias He authored
commit 483001c7 upstream. blk_cleanup_queue() will call blk_drian_queue() to drain all the requests before queue DEAD marking. If we reset the device before blk_cleanup_queue() the drain would fail. 1) if the queue is stopped in do_virtblk_request() because device is full, the q->request_fn() will not be called. blk_drain_queue() { while(true) { ... if (!list_empty(&q->queue_head)) __blk_run_queue(q) { if (queue is not stoped) q->request_fn() } ... } } Do no reset the device before blk_cleanup_queue() gives the chance to start the queue in interrupt handler blk_done(). 2) In commit b79d866c, We abort requests dispatched to driver before blk_cleanup_queue(). There is a race if requests are dispatched to driver after the abort and before the queue DEAD mark. To fix this, instead of aborting the requests explicitly, we can just reset the device after after blk_cleanup_queue so that the device can complete all the requests before queue DEAD marking in the drain process. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: virtualization@lists.linux-foundation.org Cc: kvm@vger.kernel.org Signed-off-by:
Asias He <asias@redhat.com> Acked-by:
Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
Rusty Russell <rusty@rustcorp.com.au> Signed-off-by:
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Asias He authored
commit 02e2b124 upstream. del_gendisk() might not return due to failing to remove the /sys/block/vda/serial sysfs entry when another thread (udev) is trying to read it. virtblk_remove() vdev->config->reset() : guest will not kick us through interrupt del_gendisk() device_del() kobject_del(): got stuck, sysfs entry ref count non zero sysfs_open_file(): user space process read /sys/block/vda/serial sysfs_get_active() : got sysfs entry ref count dev_attr_show() virtblk_serial_show() blk_execute_rq() : got stuck, interrupt is disabled request cannot be finished This patch fixes it by calling del_gendisk() before we disable guest's interrupt so that the request sent in virtblk_serial_show() will be finished and del_gendisk() will success. This fixes another race in hot-unplug process. It is save to call del_gendisk(vblk->disk) before flush_work(&vblk->config_work) which might access vblk->disk, because vblk->disk is not freed until put_disk(vblk->disk). Cc: virtualization@lists.linux-foundation.org Cc: kvm@vger.kernel.org Signed-off-by:
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Asias He authored
commit b79d866c upstream. If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so the drain will not finish. How to reproduce the race: 1. hot-plug a virtio-blk device 2. keep reading/writing the device in guest 3. hot-unplug while the device is busy serving I/O Test: ~1000 rounds of hot-plug/hot-unplug test passed with this patch. Changes in v3: - Drop blk_abort_queue and blk_abort_request - Use __blk_end_request_all to complete request dispatched to driver Changes in v2: - Drop req_in_flight - Use virtqueue_detach_unused_buf to get request dispatched to driver Signed-off-by:
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Asias He authored
commit f65ca1dc upstream. Benchmark shows small performance improvement on fusion io device. Before: seq-read : io=1,024MB, bw=19,982KB/s, iops=39,964, runt= 52475msec seq-write: io=1,024MB, bw=20,321KB/s, iops=40,641, runt= 51601msec rnd-read : io=1,024MB, bw=15,404KB/s, iops=30,808, runt= 68070msec rnd-write: io=1,024MB, bw=14,776KB/s, iops=29,552, runt= 70963msec After: seq-read : io=1,024MB, bw=20,343KB/s, iops=40,685, runt= 51546msec seq-write: io=1,024MB, bw=20,803KB/s, iops=41,606, runt= 50404msec rnd-read : io=1,024MB, bw=16,221KB/s, iops=32,442, runt= 64642msec rnd-write: io=1,024MB, bw=15,199KB/s, iops=30,397, runt= 68991msec Signed-off-by:
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Michael S. Tsirkin authored
commit 4678d6f9 upstream. Fix a theoretical race related to config work handler: a config interrupt might happen after we flush config work but before we reset the device. It will then cause the config work to run during or after reset. Two problems with this: - if this runs after device is gone we will get use after free - access of config while reset is in progress is racy (as layout is changing). As a solution 1. flush after reset when we know there will be no more interrupts 2. add a flag to disable config access before reset Signed-off-by:
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Tony Luck authored
commit d114a333 upstream. Send the entire DMI (SMBIOS) table to the /dev/random driver to help seed its pools. Signed-off-by:
Tony Luck <tony.luck@intel.com> Signed-off-by:
Theodore Ts'o <tytso@mit.edu> Signed-off-by:
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Tony Luck authored
commit cbc96b75 upstream. Many platforms have per-machine instance data (serial numbers, asset tags, etc.) squirreled away in areas that are accessed during early system bringup. Mixing this data into the random pools has a very high value in providing better random data, so we should allow (and even encourage) architecture code to call add_device_randomness() from the setup_arch() paths. However, this limits our options for internal structure of the random driver since random_initialize() is not called until long after setup_arch(). Add a big fat comment to rand_initialize() spelling out this requirement. Suggested-by:
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Theodore Ts'o authored
commit 330e0a01 upstream. Matt Mackall stepped down as the /dev/random driver maintainer last year, so Theodore Ts'o is taking back the /dev/random driver. Cc: Matt Mackall <mpm@selenic.com> Signed-off-by:
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Mathieu Desnoyers authored
commit 44e4360f upstream. /proc/sys/kernel/random/boot_id can be read concurrently by userspace processes. If two (or more) user-space processes concurrently read boot_id when sysctl_bootid is not yet assigned, a race can occur making boot_id differ between the reads. Because the whole point of the boot id is to be unique across a kernel execution, fix this by protecting this operation with a spinlock. Given that this operation is not frequently used, hitting the spinlock on each call should not be an issue. Signed-off-by:
Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by:
Eric Dumazet <eric.dumazet@gmail.com> Cc: Greg Kroah-Hartman <greg@kroah.com> Signed-off-by:
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Szymon Janc authored
commit 8f321f85 upstream. If remote device sends bogus RFC option with invalid length, undefined options values are used. Fix this by using defaults when remote misbehaves. This also fixes the following warning reported by gcc 4.7.0: net/bluetooth/l2cap_core.c: In function 'l2cap_config_rsp': net/bluetooth/l2cap_core.c:3302:13: warning: 'rfc.max_pdu_size' may be used uninitialized in this function [-Wmaybe-uninitialized] net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.max_pdu_size' was declared here net/bluetooth/l2cap_core.c:3298:25: warning: 'rfc.monitor_timeout' may be used uninitialized in this function [-Wmaybe-uninitialized] net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.monitor_timeout' was declared here net/bluetooth/l2cap_core.c:3297:25: warning: 'rfc.retrans_timeout' may be used uninitialized in this function [-Wmaybe-uninitialized] net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.retrans_timeout' was declared here net/bluetooth/l2cap_core.c:3295:2: warning: 'rfc.mode' may be used uninitialized in this function [-Wmaybe-uninitialized] net/bluetooth/l2cap_core.c:3266:24: note: 'rfc.mode' was declared here Signed-off-by:
Szymon Janc <szymon.janc@tieto.com> Signed-off-by:
Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by:
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Hugh Dickins authored
commit 676ce6d5 upstream. Commit 91f68c89 ("block: fix infinite loop in __getblk_slow") is not good: a successful call to grow_buffers() cannot guarantee that the page won't be reclaimed before the immediate next call to __find_get_block(), which is why there was always a loop there. Yesterday I got "EXT4-fs error (device loop0): __ext4_get_inode_loc:3595: inode #19278: block 664: comm cc1: unable to read itable block" on console, which pointed to this commit. I've been trying to bisect for weeks, why kbuild-on-ext4-on-loop-on-tmpfs sometimes fails from a missing header file, under memory pressure on ppc G5. I've never seen this on x86, and I've never seen it on 3.5-rc7 itself, despite that commit being in there: bisection pointed to an irrelevant pinctrl merge, but hard to tell when failure takes between 18 minutes and 38 hours (but so far it's happened quicker on 3.6-rc2). (I've since found such __ext4_get_inode_loc errors in /var/log/messages from previous weeks: why the message never appeared on console until yesterday morning is a mystery for another day.) Revert 91f68c89, restoring __getblk_slow() to how it was (plus a checkpatch nitfix). Simplify the interface between grow_buffers() and grow_dev_page(), and avoid the infinite loop beyond end of device by instead checking init_page_buffers()'s end_block there (I presume that's more efficient than a repeated call to blkdev_max_block()), returning -ENXIO to __getblk_slow() in that case. And remove akpm's ten-year-old "__getblk() cannot fail ... weird" comment, but that is worrying: are all users of __getblk() really now prepared for a NULL bh beyond end of device, or will some oops?? Signed-off-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk> Signed-off-by:
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Glauber Costa authored
commit 61065a30 upstream. While stressing the kernel with with failing allocations today, I hit the following chain of events: alloc_page_buffers(): bh = alloc_buffer_head(GFP_NOFS); if (!bh) goto no_grow; <= path taken grow_dev_page(): bh = alloc_page_buffers(page, size, 0); if (!bh) goto failed; <= taken, consequence of the above and then the failed path BUG()s the kernel. The failure is inserted a litte bit artificially, but even then, I see no reason why it should be deemed impossible in a real box. Even though this is not a condition that we expect to see around every time, failed allocations are expected to be handled, and BUG() sounds just too much. As a matter of fact, grow_dev_page() can return NULL just fine in other circumstances, so I propose we just remove it, then. Signed-off-by:
Glauber Costa <glommer@parallels.com> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by:
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Alexandre Bounine authored
commit 9a9a9a7a upstream. Fix unused variable compiler warning when built with CONFIG_RAPIDIO_DEBUG option off. This patch is applicable to kernel versions starting from v3.2 Signed-off-by:
Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Signed-off-by:
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Alexandre Bounine authored
commit 3670e7e1 upstream. Make sure that there is no doorbell messages left behind due to disabled interrupts during inbound doorbell processing. The most common case for this bug is loss of rionet JOIN messages in systems with three or more rionet participants and MSI or MSI-X enabled. As result, requests for packet transfers may finish with "destination unreachable" error message. This patch is applicable to kernel versions starting from v3.2. Signed-off-by:
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Atsushi Nemoto authored
commit 7dbfb315 upstream. Correct the offset by subtracting 20 from tm_hour before taking the modulo 12. [ "Why 20?" I hear you ask. Or at least I did. Here's the reason why: RS5C348_BIT_PM is 32, and is - stupidly - included in the RS5C348_HOURS_MASK define. So it's really subtracting out that bit to get "hour+12". But then because it does things modulo 12, it needs to add the 12 in again afterwards anyway. This code is confused. It would be much clearer if RS5C348_HOURS_MASK just didn't include the RS5C348_BIT_PM bit at all, then it wouldn't need to do the silly subtract either. Whatever. It's all just math, the end result is the same. - Linus ] Reported-by:
James Nute <newten82@gmail.com> Tested-by:
Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by:
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Robin Holt authored
commit 7838f994 upstream. On many of our larger systems, CPU 0 has had all of its IRQ resources consumed before XPC loads. Worst cases on machines with multiple 10 GigE cards and multiple IB cards have depleted the entire first socket of IRQs. This patch makes selecting the node upon which IRQs are allocated (as well as all the other GRU Message Queue structures) specifiable as a module load param and has a default behavior of searching all nodes/cpus for an available resources. [akpm@linux-foundation.org: fix build: include cpu.h and module.h] Signed-off-by:
Robin Holt <holt@sgi.com> Signed-off-by:
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Michal Hocko authored
commit eb48c071 upstream. Each page mapped in a process's address space must be correctly accounted for in _mapcount. Normally the rules for this are straightforward but hugetlbfs page table sharing is different. The page table pages at the PMD level are reference counted while the mapcount remains the same. If this accounting is wrong, it causes bugs like this one reported by Larry Woodman: kernel BUG at mm/filemap.c:135! invalid opcode: 0000 [#1] SMP CPU 22 Modules linked in: bridge stp llc sunrpc binfmt_misc dcdbas microcode pcspkr acpi_pad acpi] Pid: 18001, comm: mpitest Tainted: G W 3.3.0+ #4 Dell Inc. PowerEdge R620/07NDJ2 RIP: 0010:[<ffffffff8112cfed>] [<ffffffff8112cfed>] __delete_from_page_cache+0x15d/0x170 Process mpitest (pid: 18001, threadinfo ffff880428972000, task ffff880428b5cc20) Call Trace: delete_from_page_cache+0x40/0x80 truncate_hugepages+0x115/0x1f0 hugetlbfs_evict_inode+0x18/0x30 evict+0x9f/0x1b0 iput_final+0xe3/0x1e0 iput+0x3e/0x50 d_kill+0xf8/0x110 dput+0xe2/0x1b0 __fput+0x162/0x240 During fork(), copy_hugetlb_page_range() detects if huge_pte_alloc() shared page tables with the check dst_pte == src_pte. The logic is if the PMD page is the same, they must be shared. This assumes that the sharing is between the parent and child. However, if the sharing is with a different process entirely then this check fails as in this diagram: parent | ------------>pmd src_pte----------> data page ^ other--------->pmd--------------------| ^ child-----------| dst_pte For this situation to occur, it must be possible for Parent and Other to have faulted and failed to share page tables with each other. This is possible due to the following style of race. PROC A PROC B copy_hugetlb_page_range copy_hugetlb_page_range src_pte == huge_pte_offset src_pte == huge_pte_offset !src_pte so no sharing !src_pte so no sharing (time passes) hugetlb_fault hugetlb_fault huge_pte_alloc huge_pte_alloc huge_pmd_share huge_pmd_share LOCK(i_mmap_mutex) find nothing, no sharing UNLOCK(i_mmap_mutex) LOCK(i_mmap_mutex) find nothing, no sharing UNLOCK(i_mmap_mutex) pmd_alloc pmd_alloc LOCK(instantiation_mutex) fault UNLOCK(instantiation_mutex) LOCK(instantiation_mutex) fault UNLOCK(instantiation_mutex) These two processes are not poing to the same data page but are not sharing page tables because the opportunity was missed. When either process later forks, the src_pte == dst pte is potentially insufficient. As the check falls through, the wrong PTE information is copied in (harmless but wrong) and the mapcount is bumped for a page mapped by a shared page table leading to the BUG_ON. This patch addresses the issue by moving pmd_alloc into huge_pmd_share which guarantees that the shared pud is populated in the same critical section as pmd. This also means that huge_pte_offset test in huge_pmd_share is serialized correctly now which in turn means that the success of the sharing will be higher as the racing tasks see the pud and pmd populated together. Race identified and changelog written mostly by Mel Gorman. {akpm@linux-foundation.org: attempt to make the huge_pmd_share() comment comprehensible, clean up coding style] Reported-by:
Larry Woodman <lwoodman@redhat.com> Tested-by:
Michal Hocko <mhocko@suse.cz> Reviewed-by:
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Stephen M. Cameron authored
commit b0cf0b11 upstream. Delete code which sets SCSI status incorrectly as it's already been set correctly above this incorrect code. The bug was introduced in 2009 by commit b0e15f6d ("cciss: fix typo that causes scsi status to be lost.") Signed-off-by:
Stephen M. Cameron <scameron@beardog.cce.hp.com> Reported-by:
Roel van Meer <roel.vanmeer@bokxing.nl> Tested-by:
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Dave Airlie authored
commit d8636a27 upstream. So we've had a fair few reports of fbcon handover breakage between efi/vesafb and i915 surface recently, so I dedicated a couple of days to finding the problem. Essentially the last thing we saw was the conflicting framebuffer message and that was all. So after much tracing with direct netconsole writes (printks under console_lock not so useful), I think I found the race. Thread A (driver load) Thread B (timer thread) unbind_con_driver -> | bind_con_driver -> | vc->vc_sw->con_deinit -> | fbcon_deinit -> | console_lock() | | | | fbcon_flashcursor timer fires | console_lock() <- blocked for A | | fbcon_del_cursor_timer -> del_timer_sync (BOOM) Of course because all of this is under the console lock, we never see anything, also since we also just unbound the active console guess what we never see anything. Hopefully this fixes the problem for anyone seeing vesafb->kms driver handoff. v1.1: add comment suggestion from Alan. Signed-off-by:
Dave Airlie <airlied@redhat.com> Signed-off-by:
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Alex Deucher authored
commit 676bc2e1 upstream. This reverts commit d1c7871d. ttm_bo_init() destroys the BO on failure. So this patch makes the retry path work with freed memory. This ends up causing kernel panics when this path is hit. Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> [bwh: Backported to 3.2: adjust context] Signed-off-by:
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J. Bruce Fields authored
commit d10f27a7 upstream. The rpc server tries to ensure that there will be room to send a reply before it receives a request. It does this by tracking, in xpt_reserved, an upper bound on the total size of the replies that is has already committed to for the socket. Currently it is adding in the estimate for a new reply *before* it checks whether there is space available. If it finds that there is not space, it then subtracts the estimate back out. This may lead the subsequent svc_xprt_enqueue to decide that there is space after all. The results is a svc_recv() that will repeatedly return -EAGAIN, causing server threads to loop without doing any actual work. Reported-by:
Michael Tokarev <mjt@tls.msk.ru> Tested-by:
J. Bruce Fields <bfields@redhat.com> Signed-off-by:
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J. Bruce Fields authored
commit f06f00a2 upstream. svc_tcp_sendto sets XPT_CLOSE if we fail to transmit the entire reply. However, the XPT_CLOSE won't be acted on immediately. Meanwhile other threads could send further replies before the socket is really shut down. This can manifest as data corruption: for example, if a truncated read reply is followed by another rpc reply, that second reply will look to the client like further read data. Symptoms were data corruption preceded by svc_tcp_sendto logging something like kernel: rpc-srv/tcp: nfsd: sent only 963696 when sending 1048708 bytes - shutting down socket Reported-by:
Malahal Naineni <malahal@us.ibm.com> Tested-by:
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J. Bruce Fields authored
commit be1e4444 upstream. Examination of svc_tcp_clear_pages shows that it assumes sk_tcplen is consistent with sk_pages[] (in particular, sk_pages[n] can't be NULL if sk_tcplen would lead us to expect n pages of data). svc_tcp_restore_pages zeroes out sk_pages[] while leaving sk_tcplen. This is OK, since both functions are serialized by XPT_BUSY. However, that means the inconsistency must be repaired before dropping XPT_BUSY. Therefore we should be ensuring that svc_tcp_save_pages repairs the problem before exiting svc_tcp_recv_record on error. Symptoms were a BUG() in svc_tcp_clear_pages. Signed-off-by:
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Al Viro authored
commit 0e665d5d upstream. compat_sys_{read,write}v() need the same "pass a copy of file->f_pos" thing as sys_{read,write}{,v}(). Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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Trond Myklebust authored
commit 08660043 upstream. If the rpc call to NFS3PROC_FSINFO fails, then we need to report that error so that the mount fails. Otherwise we can end up with a superblock with completely unusable values for block sizes, maxfilesize, etc. Reported-by:
Yuanming Chen <hikvision_linux@163.com> Signed-off-by:
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Alex Deucher authored
commit c61e2775 upstream. There are systems that use ATRM, but not ATPX. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=41265 V2: fix #ifdefs as per Greg's comments V3: fix it harder Signed-off-by:
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