- 20 Aug, 2013 9 commits
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Marc Zyngier authored
commit 6a077e4a upstream. Not saving PAR is an unfortunate oversight. If the guest performs an AT* operation and gets scheduled out before reading the result of the translation from PAR, it could become corrupted by another guest or the host. Saving this register is made slightly more complicated as KVM also uses it on the permission fault handling path, leading to an ugly "stash and restore" sequence. Fortunately, this is already a slow path so we don't really care. Also, Linux doesn't do any AT* operation, so Linux guests are not impacted by this bug. [ Slightly tweaked to use an even register as first operand to ldrd and strd operations in interrupts_head.S - Christoffer ] Signed-off-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by:
Jonghwan Choi <jhbird.choi@samsung.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Jianpeng Ma authored
commit d50235b7 upstream. There's a race between elevator switching and normal io operation. Because the allocation of struct elevator_queue and struct elevator_data don't in a atomic operation.So there are have chance to use NULL ->elevator_data. For example: Thread A: Thread B blk_queu_bio elevator_switch spin_lock_irq(q->queue_block) elevator_alloc elv_merge elevator_init_fn Because call elevator_alloc, it can't hold queue_lock and the ->elevator_data is NULL.So at the same time, threadA call elv_merge and nedd some info of elevator_data.So the crash happened. Move the elevator_alloc into func elevator_init_fn, it make the operations in a atomic operation. Using the follow method can easy reproduce this bug 1:dd if=/dev/sdb of=/dev/null 2:while true;do echo noop > scheduler;echo deadline > scheduler;done The test method also use this method. Signed-off-by:
Jianpeng Ma <majianpeng@gmail.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk> Cc: Jonghwan Choi <jhbird.choi@samsung.com> Signed-off-by:
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Peter Zijlstra authored
commit bf0bd948 upstream. We typically update a task_group's shares within the dequeue/enqueue path. However, continuously running tasks sharing a CPU are not subject to these updates as they are only put/picked. Unfortunately, when we reverted f269ae04 (in 17bc14b7), we lost the augmenting periodic update that was supposed to account for this; resulting in a potential loss of fairness. To fix this, re-introduce the explicit update in update_cfs_rq_blocked_load() [called via entity_tick()]. Reported-by:
Max Hailperin <max@gustavus.edu> Signed-off-by:
Peter Zijlstra <peterz@infradead.org> Reviewed-by:
Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/n/tip-9545m3apw5d93ubyrotrj31y@git.kernel.orgSigned-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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yonghua zheng authored
commit 8c829622 upstream. Recently we met quite a lot of random kernel panic issues after enabling CONFIG_PROC_PAGE_MONITOR. After debuggind we found this has something to do with following bug in pagemap: In struct pagemapread: struct pagemapread { int pos, len; pagemap_entry_t *buffer; bool v2; }; pos is number of PM_ENTRY_BYTES in buffer, but len is the size of buffer, it is a mistake to compare pos and len in add_page_map() for checking buffer is full or not, and this can lead to buffer overflow and random kernel panic issue. Correct len to be total number of PM_ENTRY_BYTES in buffer. [akpm@linux-foundation.org: document pagemapread.pos and .len units, fix PM_ENTRY_BYTES definition] Signed-off-by:
Yonghua Zheng <younghua.zheng@gmail.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Radu Caragea authored
commit df54d6fa upstream. When the stack is set to unlimited, the bottomup direction is used for mmap-ings but the mmap_base is not used and thus effectively renders ASLR for mmapings along with PIE useless. Reviewed-by:
Rik van Riel <riel@redhat.com> Cc: Michel Lespinasse <walken@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Acked-by:
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Michal Simek authored
commit dfa9771a upstream. Fix inadvertent breakage in the clone syscall ABI for Microblaze that was introduced in commit f3268edb ("microblaze: switch to generic fork/vfork/clone"). The Microblaze syscall ABI for clone takes the parent tid address in the 4th argument; the third argument slot is used for the stack size. The incorrectly-used CLONE_BACKWARDS type assigned parent tid to the 3rd slot. This commit restores the original ABI so that existing userspace libc code will work correctly. All kernel versions from v3.8-rc1 were affected. Signed-off-by:
Michal Simek <michal.simek@xilinx.com> Signed-off-by:
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Andrey Vagin authored
commit 3e6b11df upstream. struct memcg_cache_params has a union. Different parts of this union are used for root and non-root caches. A part with destroying work is used only for non-root caches. I fixed the same problem in another place v3.9-rc1-16204-gf101a946, but didn't notice this one. This patch fixes the kernel panic: [ 46.848187] BUG: unable to handle kernel paging request at 000000fffffffeb8 [ 46.849026] IP: [<ffffffff811a484c>] kmem_cache_destroy_memcg_children+0x6c/0xc0 [ 46.849092] PGD 0 [ 46.849092] Oops: 0000 [#1] SMP ... Signed-off-by:
Andrey Vagin <avagin@openvz.org> Cc: Glauber Costa <glommer@openvz.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by:
Michal Hocko <mhocko@suse.cz> Cc: Balbir Singh <bsingharora@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by:
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Stephen Boyd authored
commit b88a2595 upstream. Fix constraint check in armpmu_map_hw_event(). Reported-and-tested-by:
Vince Weaver <vincent.weaver@maine.edu> Signed-off-by:
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Vince Weaver authored
commit c9601247 upstream. John McCalpin reports that the "drs_data" and "ncb_data" QPI uncore events are missing the "extra bit" and always return zero values unless the bit is properly set. More details from him: According to the Xeon E5-2600 Product Family Uncore Performance Monitoring Guide, Table 2-94, about 1/2 of the QPI Link Layer events (including the ones that "perf" calls "drs_data" and "ncb_data") require that the "extra bit" be set. This was confusing for a while -- a note at the bottom of page 94 says that the "extra bit" is bit 16 of the control register. Unfortunately, Table 2-86 clearly says that bit 16 is reserved and must be zero. Looking around a bit, I found that bit 21 appears to be the correct "extra bit", and further investigation shows that "perf" actually agrees with me: [root@c560-003.stampede]# cat /sys/bus/event_source/devices/uncore_qpi_0/format/event config:0-7,21 So the command # perf -e "uncore_qpi_0/event=drs_data/" Is the same as # perf -e "uncore_qpi_0/event=0x02,umask=0x08/" While it should be # perf -e "uncore_qpi_0/event=0x102,umask=0x08/" I confirmed that this last version gives results that agree with the amount of data that I expected the STREAM benchmark to move across the QPI link in the second (cross-chip) test of the original script. Reported-by:
John McCalpin <mccalpin@tacc.utexas.edu> Signed-off-by:
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- 15 Aug, 2013 31 commits
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Greg Kroah-Hartman authored
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Markos Chandras authored
commit 78857614 upstream. The GENERIC_PCI_IOMAP does not depend on CONFIG_PCI so move it to the CONFIG_MIPS symbol so it's always selected for MIPS. This fixes the missing pci_iomap declaration for MIPS. Moreover, the pci_iounmap function was not defined in the io.h header file if the CONFIG_PCI symbol is not set, but it should since MIPS is not using CONFIG_GENERIC_IOMAP. This fixes the following problem on a allyesconfig: drivers/net/ethernet/3com/3c59x.c:1031:2: error: implicit declaration of function 'pci_iomap' [-Werror=implicit-function-declaration] drivers/net/ethernet/3com/3c59x.c:1044:3: error: implicit declaration of function 'pci_iounmap' [-Werror=implicit-function-declaration] Signed-off-by:
Markos Chandras <markos.chandras@imgtec.com> Acked-by:
Steven J. Hill <Steven.Hill@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/5478/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by:
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Arnd Bergmann authored
commit 930d800b upstream. The omap2 nand device driver calls into the the elm code, which can be a loadable module, and in that case it cannot be built-in itself. I can see no reason why the omap2 driver cannot also be a module, so let's make the option "tristate" in Kconfig to fix this allmodconfig build error: ERROR: "elm_config" [drivers/mtd/nand/omap2.ko] undefined! ERROR: "elm_decode_bch_error_page" [drivers/mtd/nand/omap2.ko] undefined! Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Acked-by:
Tony Lindgren <tony@atomide.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Afzal Mohammed <afzal@ti.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by:
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Arnd Bergmann authored
commit b497ceb9 upstream. ARM cannot handle udelay for more than 2 miliseconds, so we should use mdelay instead for those. Signed-off-by:
GOTO Masanori <gotom@debian.or.jp> Cc: YOKOTA Hiroshi <yokota@netlab.is.tsukuba.ac.jp> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by:
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Alex Deucher authored
commit 6fab3feb upstream. For r6xx+ asics. This mirrors the behavior of pre-r6xx asics. We need to program the MC even if something else in startup() fails. Failure to do so results in an unusable GPU. Based on a fix from: Mark Kettenis <kettenis@openbsd.org> Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> [ rebased for 3.10 and dropped the drivers/gpu/drm/radeon/cik.c bit as it's 3.11 specific code / tmb ] Signed-off-by:
Thomas Backlund <tmb@mageia.org> Signed-off-by:
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Christian König authored
commit 4ad9c1c7 upstream. Otherwise just reinitialize from scratch on resume, and so make it more likely to succeed. v2: rebased for 3.10-stable tree Signed-off-by:
Christian König <christian.koenig@amd.com> Cc: stable@vger.kernel.org Signed-off-by:
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Christian König authored
commit 2858c00d upstream. Removing the clock/power or resetting the VCPU can cause hangs if that happens in the middle of a register write. Stall the memory and register bus before putting the VCPU into reset. Keep it in reset when unloading the module or suspending. v2: rebased on 3.10-stable tree Signed-off-by:
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Jani Nikula authored
commit 14c5cec5 upstream. commit 181d1b9e Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Sun Jul 21 13:16:24 2013 +0200 drm/i915: fix up gt init sequence fallout moved dev_priv->gt_lock initialization after use. Do the initialization much earlier with other spin lock initializations. Reported-by:
Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by:
Jani Nikula <jani.nikula@intel.com> Tested-by:
Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by:
Zhouping Liu <zliu@redhat.com> Signed-off-by:
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Al Viro authored
commit 672fe15d upstream. Since remove_proc_entry() started to wait for IO in progress (i.e. since 2007 or so), the locking in fs/reiserfs/proc.c became wrong; if procfs read happens between the moment when umount() locks the victim superblock and removal of /proc/fs/reiserfs/<device>/*, we'll get a deadlock - read will wait for s_umount (in sget(), called by r_start()), while umount will wait in remove_proc_entry() for that read to finish, holding s_umount all along. Fortunately, the same change allows a much simpler race avoidance - all we need to do is remove the procfs entries in the very beginning of reiserfs ->kill_sb(); that'll guarantee that pointer to superblock will remain valid for the duration for procfs IO, so we don't need sget() to keep the sucker alive. As the matter of fact, we can get rid of the home-grown iterator completely, and use single_open() instead. Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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Oleg Nesterov authored
commit 776164c1 upstream. debugfs_remove_recursive() is wrong, 1. it wrongly assumes that !list_empty(d_subdirs) means that this dir should be removed. This is not that bad by itself, but: 2. if d_subdirs does not becomes empty after __debugfs_remove() it gives up and silently fails, it doesn't even try to remove other entries. However ->d_subdirs can be non-empty because it still has the already deleted !debugfs_positive() entries. 3. simple_release_fs() is called even if __debugfs_remove() fails. Suppose we have dir1/ dir2/ file2 file1 and someone opens dir1/dir2/file2. Now, debugfs_remove_recursive(dir1/dir2) succeeds, and dir1/dir2 goes away. But debugfs_remove_recursive(dir1) silently fails and doesn't remove this directory. Because it tries to delete (the already deleted) dir1/dir2/file2 again and then fails due to "Avoid infinite loop" logic. Test-case: #!/bin/sh cd /sys/kernel/debug/tracing echo 'p:probe/sigprocmask sigprocmask' >> kprobe_events sleep 1000 < events/probe/sigprocmask/id & echo -n >| kprobe_events [ -d events/probe ] && echo "ERR!! failed to rm probe" And after that it is not possible to create another probe entry. With this patch debugfs_remove_recursive() skips !debugfs_positive() files although this is not strictly needed. The most important change is that it does not try to make ->d_subdirs empty, it simply scans the whole list(s) recursively and removes as much as possible. Link: http://lkml.kernel.org/r/20130726151256.GC19472@redhat.comAcked-by:
Oleg Nesterov <oleg@redhat.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Julius Werner authored
commit 481f2d4f upstream. The USB hub driver's event handler contains a check to catch SuperSpeed devices that transitioned into the SS.Inactive state and tries to fix them with a reset. It decides whether to do a plain hub port reset or call the usb_reset_device() function based on whether there was a device attached to the port. However, there are device/hub combinations (found with a JetFlash Transcend mass storage stick (8564:1000) on the root hub of an Intel LynxPoint PCH) which can transition to the SS.Inactive state on disconnect (and stay there long enough for the host to notice). In this case, above-mentioned reset check will call usb_reset_device() on the stale device data structure. The kernel will send pointless LPM control messages to the no longer connected device address and can even cause several 5 second khubd stalls on some (buggy?) host controllers, before finally accepting the device's fate amongst a flurry of error messages. This patch makes the choice of reset dependent on the port status that has just been read from the hub in addition to the existence of an in-kernel data structure for the device, and only proceeds with the more extensive reset if both are valid. Signed-off-by:
Julius Werner <jwerner@chromium.org> Signed-off-by:
Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by:
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Sergey Senozhatsky authored
commit 75c7caf5 upstream. Pass valid_io_request() checks if request end coincides with disksize (end equals bound), only fail if we attempt to read beyond the bound. mkfs.ext2 produces numerous errors: [ 2164.632747] quiet_error: 1 callbacks suppressed [ 2164.633260] Buffer I/O error on device zram0, logical block 153599 [ 2164.633265] lost page write due to I/O error on zram0 Signed-off-by:
Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Thomas Backlund <tmb@mageia.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by:
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Jeff Layton authored
commit 757c4f62 upstream. David reported that commit c2b93e06 (cifs: only set ops for inodes in I_NEW state) caused a regression with mfsymlinks. Prior to that patch, if a mfsymlink dentry was instantiated at readdir time, the inode would get a new set of ops when it was revalidated. After that patch, this did not occur. This patch addresses this by simply skipping instantiating dentries in the readdir codepath when we know that they will need to be immediately revalidated. The next attempt to use that dentry will cause a new lookup to occur (which is basically what we want to happen anyway). Reported-and-Tested-by:
David McBride <dwm37@cam.ac.uk> Cc: "Stefan (metze) Metzmacher" <metze@samba.org> Cc: Sachin Prabhu <sprabhu@redhat.com> Signed-off-by:
Jeff Layton <jlayton@redhat.com> Signed-off-by:
Steve French <smfrench@gmail.com> Signed-off-by:
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Chen Gang authored
commit 057d6332 upstream. For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName' length may be "255 + '\0'". The related sprintf() may cause memory overflow, so need extend related buffer enough to hold all things. It is also necessary to be sure of 'ses->domainName' must be less than 256, and define the related macro instead of hard code number '256'. Signed-off-by:
Chen Gang <gang.chen@asianux.com> Reviewed-by:
Shirish Pargaonkar <shirishpargaonkar@gmail.com> Reviewed-by:
Scott Lovenberg <scott.lovenberg@gmail.com> Signed-off-by:
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Theodore Ts'o authored
commit cde2d7a7 upstream. Previously we weren't swapping only some of the extent_status LRU fields during the processing of the EXT4_IOC_SWAP_BOOT ioctl. The much safer thing to do is to just completely flush the extent status tree when doing the swap. Signed-off-by:
"Theodore Ts'o" <tytso@mit.edu> Cc: Zheng Liu <gnehzuil.liu@gmail.com> Signed-off-by:
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Piotr Sarna authored
commit 6ae6514b upstream. Commit 56889787 ("ext4: improve handling of conflicting mount options") introduced incorrect messages shown while choosing wrong mount options. First of all, both cases of incorrect mount options, "data=journal,delalloc" and "data=journal,dioread_nolock" result in the same error message. Secondly, the problem above isn't solved for remount option: the mismatched parameter is simply ignored. Moreover, ext4_msg states that remount with options "data=journal,delalloc" succeeded, which is not true. To fix it up, I added a simple check after parse_options() call to ensure that data=journal and delalloc/dioread_nolock parameters are not present at the same time. Signed-off-by:
Piotr Sarna <p.sarna@partner.samsung.com> Acked-by:
Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by:
Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by:
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Theodore Ts'o authored
commit 59d9fa5c upstream. Commit 26092bf5 ("ext4: use a table-driven handler for mount options") wrongly disallows the specifying the mount options nodelalloc and data=journal simultaneously. This is incorrect; it should have only disallowed the combination of delalloc and data=journal simultaneously. Reported-by:
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Christian König authored
commit 641a0059 upstream. We also need to check the handle. Signed-off-by:
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Alex Deucher authored
commit e1accbf0 upstream. There are two audio dtos on radeon asics that you can select between. Normally, dto0 is used for hdmi and dto1 for DP, but it seems that the dto is somehow tied to the encoders on DCE3 asics. fixes: https://bugs.freedesktop.org/show_bug.cgi?id=67435Signed-off-by:
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Michel Dänzer authored
commit e91abf80 upstream. It takes an unsigned value. This happens not to blow up on 64-bit architectures, but it does on 32-bit, causing drm_calc_vbltimestamp_from_scanoutpos() to calculate totally bogus timestamps for vblank events. Which in turn causes e.g. gnome-shell to hang after a DPMS off cycle with current xf86-video-ati Git. [airlied: regression introduced in drm: use monotonic time in drm_calc_vbltimestamp_from_scanoutpos] Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59339 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59836Tested-by:
shui yangwei <yangweix.shui@intel.com> Signed-off-by:
Michel Dänzer <michel.daenzer@amd.com> Reviewed-by:
Imre Deak <imre.deak@intel.com> Signed-off-by:
Dave Airlie <airlied@redhat.com> Signed-off-by:
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Dave Airlie authored
commit 3ac65259 upstream. same fix as cirrus and mgag200. Signed-off-by:
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Egbert Eich authored
commit ecaac1c8 upstream. When a BO gets pinned the placement may get changed. If the memory is mapped into user space and user space has already accessed the mapped range the page tables are set up but now point to the wrong memory. Set bo.mdev->dev_mapping in mgag200_bo_create() to make sure that ttm_bo_unmap_virtual() called from ttm_bo_handle_move_mem() will take care of this. v2: Don't call ttm_bo_unmap_virtual() in mgag200_bo_pin(), fix comment. Signed-off-by:
Egbert Eich <eich@suse.com> Signed-off-by:
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Michal Srb authored
commit 109a5159 upstream. This is a cirrus version of Egbert Eich's patch for mgag200. Without bo.bdev->dev_mapping set, the ttm_bo_unmap_virtual_locked called from ttm_bo_handle_move_mem returns with no effect. If any application accessed the memory before it was moved, it will access wrong memory next time. This causes crashes when changing resolution down. Signed-off-by:
Michal Srb <msrb@suse.com> Signed-off-by:
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Amit Shah authored
commit 96f97a83 upstream. If a port gets unplugged while a user is blocked on read(), -ENODEV is returned. However, subsequent read()s returned 0, indicating there's no host-side connection (but not indicating the device went away). This also happened when a port was unplugged and the user didn't have any blocking operation pending. If the user didn't monitor the SIGIO signal, they won't have a chance to find out if the port went away. Fix by returning -ENODEV on all read()s after the port gets unplugged. write() already behaves this way. Signed-off-by:
Amit Shah <amit.shah@redhat.com> Signed-off-by:
Rusty Russell <rusty@rustcorp.com.au> Signed-off-by:
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Amit Shah authored
commit 92d34538 upstream. SIGIO should be sent when a port gets unplugged. It should only be sent to prcesses that have the port opened, and have asked for SIGIO to be delivered. We were clearing out guest_connected before calling send_sigio_to_port(), resulting in a sigio not getting sent to processes. Fix by setting guest_connected to false after invoking the sigio function. Signed-off-by:
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Amit Shah authored
commit ea3768b4 upstream. We used to keep the port's char device structs and the /sys entries around till the last reference to the port was dropped. This is actually unnecessary, and resulted in buggy behaviour: 1. Open port in guest 2. Hot-unplug port 3. Hot-plug a port with the same 'name' property as the unplugged one This resulted in hot-plug being unsuccessful, as a port with the same name already exists (even though it was unplugged). This behaviour resulted in a warning message like this one: -------------------8<--------------------------------------- WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted) Hardware name: KVM sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1' Call Trace: [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60 [<ffffffff812734b4>] ? kobject_add+0x44/0x70 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0 [<ffffffff8134b389>] ? device_add+0xc9/0x650 -------------------8<--------------------------------------- Instead of relying on guest applications to release all references to the ports, we should go ahead and unregister the port from all the core layers. Any open/read calls on the port will then just return errors, and an unplug/plug operation on the host will succeed as expected. This also caused buggy behaviour in case of the device removal (not just a port): when the device was removed (which means all ports on that device are removed automatically as well), the ports with active users would clean up only when the last references were dropped -- and it would be too late then to be referencing char device pointers, resulting in oopses: -------------------8<--------------------------------------- PID: 6162 TASK: ffff8801147ad500 CPU: 0 COMMAND: "cat" #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5 [exception RIP: strlen+2] RIP: ffffffff81272ae2 RSP: ffff88011b9d5d00 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff880118901c18 RCX: 0000000000000000 RDX: ffff88011799982c RSI: 00000000000000d0 RDI: 3a303030302f3030 RBP: ffff88011b9d5d38 R8: 0000000000000006 R9: ffffffffa0134500 R10: 0000000000001000 R11: 0000000000001000 R12: ffff880117a1cc10 R13: 00000000000000d0 R14: 0000000000000017 R15: ffffffff81aff700 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb #9 [ffff88011b9d5de0] device_del at ffffffff813440c7 -------------------8<--------------------------------------- So clean up when we have all the context, and all that's left to do when the references to the port have dropped is to free up the port struct itself. Reported-by:
chayang <chayang@redhat.com> Reported-by:
YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com> Reported-by:
FuXiangChun <xfu@redhat.com> Reported-by:
Qunfang Zhang <qzhang@redhat.com> Reported-by:
Sibiao Luo <sluo@redhat.com> Signed-off-by:
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Amit Shah authored
commit 671bdea2 upstream. Between open() being called and processed, the port can be unplugged. Check if this happened, and bail out. A simple test script to reproduce this is: while true; do for i in $(seq 1 100); do echo $i > /dev/vport0p3; done; done; This opens and closes the port a lot of times; unplugging the port while this is happening triggers the bug. Signed-off-by:
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Amit Shah authored
commit 057b82be upstream. There's a window between find_port_by_devt() returning a port and us taking a kref on the port, where the port could get unplugged. Fix it by taking the reference in find_port_by_devt() itself. Problem reported and analyzed by Mateusz Guzik. Reported-by:
Mateusz Guzik <mguzik@redhat.com> Signed-off-by:
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Yoshihiro YUNOMAE authored
commit 2b4fbf02 upstream. Add pipe_lock/unlock for splice_write to avoid oops by following competition: (1) An application gets fds of a trace buffer, virtio-serial, pipe. (2) The application does fork() (3) The processes execute splice_read(trace buffer) and splice_write(virtio-serial) via same pipe. <parent> <child> get fds of a trace buffer, virtio-serial, pipe | fork()----------create--------+ | | splice(read) | ---+ splice(write) | +-- no competition | splice(read) | | splice(write) ---+ | | splice(read) | splice(write) splice(read) ------ competition | splice(write) Two processes share a pipe_inode_info structure. If the child execute splice(read) when the parent tries to execute splice(write), the structure can be broken. Existing virtio-serial driver does not get lock for the structure in splice_write, so this competition will induce oops. <oops messages> BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: [<ffffffff811a6b5f>] splice_from_pipe_feed+0x6f/0x130 PGD 7223e067 PUD 72391067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: lockd bnep bluetooth rfkill sunrpc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_timer snd soundcore pcspkr virtio_net virtio_balloon i2c_piix4 i2c_core microcode uinput floppy CPU: 0 PID: 1072 Comm: compete-test Not tainted 3.10.0ws+ #55 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 task: ffff880071b98000 ti: ffff88007b55e000 task.ti: ffff88007b55e000 RIP: 0010:[<ffffffff811a6b5f>] [<ffffffff811a6b5f>] splice_from_pipe_feed+0x6f/0x130 RSP: 0018:ffff88007b55fd78 EFLAGS: 00010287 RAX: 0000000000000000 RBX: ffff88007b55fe20 RCX: 0000000000000000 RDX: 0000000000001000 RSI: ffff88007a95ba30 RDI: ffff880036f9e6c0 RBP: ffff88007b55fda8 R08: 00000000000006ec R09: ffff880077626708 R10: 0000000000000003 R11: ffffffff8139ca59 R12: ffff88007a95ba30 R13: 0000000000000000 R14: ffffffff8139dd00 R15: ffff880036f9e6c0 FS: 00007f2e2e3a0740(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000018 CR3: 0000000071bd1000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffffffff8139ca59 ffff88007b55fe20 ffff880036f9e6c0 ffffffff8139dd00 ffff8800776266c0 ffff880077626708 ffff88007b55fde8 ffffffff811a6e8e ffff88007b55fde8 ffffffff8139ca59 ffff880036f9e6c0 ffff88007b55fe20 Call Trace: [<ffffffff8139ca59>] ? alloc_buf.isra.13+0x39/0xb0 [<ffffffff8139dd00>] ? virtcons_restore+0x100/0x100 [<ffffffff811a6e8e>] __splice_from_pipe+0x7e/0x90 [<ffffffff8139ca59>] ? alloc_buf.isra.13+0x39/0xb0 [<ffffffff8139d739>] port_fops_splice_write+0xe9/0x140 [<ffffffff8127a3f4>] ? selinux_file_permission+0xc4/0x120 [<ffffffff8139d650>] ? wait_port_writable+0x1b0/0x1b0 [<ffffffff811a6fe0>] do_splice_from+0xa0/0x110 [<ffffffff811a951f>] SyS_splice+0x5ff/0x6b0 [<ffffffff8161facf>] tracesys+0xdd/0xe2 Code: 49 8b 87 80 00 00 00 4c 8d 24 d0 8b 53 04 41 8b 44 24 0c 4d 8b 6c 24 10 39 d0 89 03 76 02 89 13 49 8b 44 24 10 4c 89 e6 4c 89 ff <ff> 50 18 85 c0 0f 85 aa 00 00 00 48 89 da 4c 89 e6 4c 89 ff 41 RIP [<ffffffff811a6b5f>] splice_from_pipe_feed+0x6f/0x130 RSP <ffff88007b55fd78> CR2: 0000000000000018 ---[ end trace 24572beb7764de59 ]--- V2: Fix a locking problem for error V3: Add Reviewed-by lines and stable@ line in sign-off area Signed-off-by:
Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Reviewed-by:
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Amit Shah <amit.shah@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by:
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Yoshihiro YUNOMAE authored
commit 68c034fe upstream. Quit from splice_write if pipe->nrbufs is 0 for avoiding oops in virtio-serial. When an application was doing splice from a kernel buffer to virtio-serial on a guest, the application received signal(SIGINT). This situation will normally happen, but the kernel executed a kernel panic by oops as follows: BUG: unable to handle kernel paging request at ffff882071c8ef28 IP: [<ffffffff812de48f>] sg_init_table+0x2f/0x50 PGD 1fac067 PUD 0 Oops: 0000 [#1] SMP Modules linked in: lockd sunrpc bnep bluetooth rfkill ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_timer snd microcode virtio_balloon virtio_net pcspkr soundcore i2c_piix4 i2c_core uinput floppy CPU: 1 PID: 908 Comm: trace-cmd Not tainted 3.10.0+ #49 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 task: ffff880071c64650 ti: ffff88007bf24000 task.ti: ffff88007bf24000 RIP: 0010:[<ffffffff812de48f>] [<ffffffff812de48f>] sg_init_table+0x2f/0x50 RSP: 0018:ffff88007bf25dd8 EFLAGS: 00010286 RAX: 0000001fffffffe0 RBX: ffff882071c8ef28 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880071c8ef48 RBP: ffff88007bf25de8 R08: ffff88007fd15d40 R09: ffff880071c8ef48 R10: ffffea0001c71040 R11: ffffffff8139c555 R12: 0000000000000000 R13: ffff88007506a3c0 R14: ffff88007c862500 R15: ffff880071c8ef00 FS: 00007f0a3646c740(0000) GS:ffff88007fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff882071c8ef28 CR3: 000000007acbb000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff880071c8ef48 ffff88007bf25e20 ffff88007bf25e88 ffffffff8139d6fa ffff88007bf25e28 ffffffff8127a3f4 0000000000000000 0000000000000000 ffff880071c8ef48 0000100000000000 0000000000000003 ffff88007bf25e08 Call Trace: [<ffffffff8139d6fa>] port_fops_splice_write+0xaa/0x130 [<ffffffff8127a3f4>] ? selinux_file_permission+0xc4/0x120 [<ffffffff8139d650>] ? wait_port_writable+0x1b0/0x1b0 [<ffffffff811a6fe0>] do_splice_from+0xa0/0x110 [<ffffffff811a951f>] SyS_splice+0x5ff/0x6b0 [<ffffffff8161f8c2>] system_call_fastpath+0x16/0x1b Code: c1 e2 05 48 89 e5 48 83 ec 10 4c 89 65 f8 41 89 f4 31 f6 48 89 5d f0 48 89 fb e8 8d ce ff ff 41 8d 44 24 ff 48 c1 e0 05 48 01 c3 <48> 8b 03 48 83 e0 fe 48 83 c8 02 48 89 03 48 8b 5d f0 4c 8b 65 RIP [<ffffffff812de48f>] sg_init_table+0x2f/0x50 RSP <ffff88007bf25dd8> CR2: ffff882071c8ef28 ---[ end trace 86323505eb42ea8f ]--- It seems to induce pagefault in sg_init_tabel() when pipe->nrbufs is equal to zero. This may happen in a following situation: (1) The application normally does splice(read) from a kernel buffer, then does splice(write) to virtio-serial. (2) The application receives SIGINT when is doing splice(read), so splice(read) is failed by EINTR. However, the application does not finish the operation. (3) The application tries to do splice(write) without pipe->nrbufs. (4) The virtio-console driver tries to touch scatterlist structure sgl in sg_init_table(), but the region is out of bound. To avoid the case, a kernel should check whether pipe->nrbufs is empty or not when splice_write is executed in the virtio-console driver. V3: Add Reviewed-by lines and stable@ line in sign-off area. Signed-off-by:
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Trond Myklebust authored
commit 786615bc upstream. If rpcbind causes our connection to the AF_LOCAL socket to close after we've registered a service, then we want to be careful about reconnecting since the mount namespace may have changed. By simply refusing to reconnect the AF_LOCAL socket in the case of unregister, we avoid the need to somehow save the mount namespace. While this may lead to some services not unregistering properly, it should be safe. Signed-off-by:
Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Nix <nix@esperi.org.uk> Cc: Jeff Layton <jlayton@redhat.com> Signed-off-by:
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