kernel/linux.git, branch v4.14.36

Linux 4.14.36

2018-04-24T07:36:40+00:00

writeback: safer lock nesting

2018-04-24T07:36:39+00:00

commit 2e898e4c0a3897ccd434adac5abb8330194f527b upstream. lock_page_memcg()/unlock_page_memcg() use spin_lock_irqsave/restore() if the page's memcg is undergoing move accounting, which occurs when a process leaves its memcg for a new one that has memory.move_charge_at_immigrate set. unlocked_inode_to_wb_begin,end() use spin_lock_irq/spin_unlock_irq() if the given inode is switching writeback domains. Switches occur when enough writes are issued from a new domain. This existing pattern is thus suspicious: lock_page_memcg(page); unlocked_inode_to_wb_begin(inode, &locked); ... unlocked_inode_to_wb_end(inode, locked); unlock_page_memcg(page); If both inode switch and process memcg migration are both in-flight then unlocked_inode_to_wb_end() will unconditionally enable interrupts while still holding the lock_page_memcg() irq spinlock. This suggests the possibility of deadlock if an interrupt occurs before unlock_page_memcg(). truncate __cancel_dirty_page lock_page_memcg unlocked_inode_to_wb_begin unlocked_inode_to_wb_end end_page_writeback test_clear_page_writeback lock_page_memcg unlock_page_memcg Due to configuration limitations this deadlock is not currently possible because we don't mix cgroup writeback (a cgroupv2 feature) and memory.move_charge_at_immigrate (a cgroupv1 feature). If the kernel is hacked to always claim inode switching and memcg moving_account, then this script triggers lockup in less than a minute: cd /mnt/cgroup/memory mkdir a b echo 1 > a/memory.move_charge_at_immigrate echo 1 > b/memory.move_charge_at_immigrate ( echo $BASHPID > a/cgroup.procs while true; do dd if=/dev/zero of=/mnt/big bs=1M count=256 done ) & while true; do sync done & sleep 1h & SLEEP=$! while true; do echo $SLEEP > a/cgroup.procs echo $SLEEP > b/cgroup.procs done The deadlock does not seem possible, so it's debatable if there's any reason to modify the kernel. I suggest we should to prevent future surprises. And Wang Long said "this deadlock occurs three times in our environment", so there's more reason to apply this, even to stable. Stable 4.4 has minor conflicts applying this patch. For a clean 4.4 patch see "[PATCH for-4.4] writeback: safer lock nesting" https://lkml.org/lkml/2018/4/11/146 Wang Long said "this deadlock occurs three times in our environment" [gthelen@google.com: v4] Link: http://lkml.kernel.org/r/20180411084653.254724-1-gthelen@google.com [akpm@linux-foundation.org: comment tweaks, struct initialization simplification] Change-Id: Ibb773e8045852978f6207074491d262f1b3fb613 Link: http://lkml.kernel.org/r/20180410005908.167976-1-gthelen@google.com Fixes: 682aa8e1a6a1 ("writeback: implement unlocked_inode_to_wb transaction and use it for stat updates") Signed-off-by: Greg Thelen Reported-by: Wang Long Acked-by: Wang Long Acked-by: Michal Hocko Reviewed-by: Andrew Morton Cc: Johannes Weiner Cc: Tejun Heo Cc: Nicholas Piggin Cc: [v4.2+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [natechancellor: Adjust context due to lack of b93b016313b3b] Signed-off-by: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

media: staging: lirc_zilog: incorrect reference counting

2018-04-24T07:36:39+00:00

[not upstream as the driver is deleted in 4.16 - gregkh] Whenever poll is called, the reference count is increased but never decreased. This means that on rmmod, the lirc_thread is not stopped, and will trample over freed memory. Zilog/Hauppauge IR driver unloaded BUG: unable to handle kernel paging request at ffffffffc17ba640 Oops: 0010 [#1] SMP CPU: 1 PID: 667 Comm: zilog-rx-i2c-1 Tainted: P C OE 4.13.16-302.fc27.x86_64 #1 Hardware name: Gigabyte Technology Co., Ltd. GA-MA790FXT-UD5P/GA-MA790FXT-UD5P, BIOS F6 08/06/2009 task: ffff964eb452ca00 task.stack: ffffb254414dc000 RIP: 0010:0xffffffffc17ba640 RSP: 0018:ffffb254414dfe78 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff964ec1b35890 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246 RBP: ffffb254414dff00 R08: 000000000000036e R09: ffff964ecfc8dfd0 R10: ffffb254414dfe78 R11: 00000000000f4240 R12: ffff964ec2bf28a0 R13: ffff964ec1b358a8 R14: ffff964ec1b358d0 R15: ffff964ec1b35800 FS: 0000000000000000(0000) GS:ffff964ecfc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffc17ba640 CR3: 000000023058c000 CR4: 00000000000006e0 Call Trace: kthread+0x125/0x140 ? kthread_park+0x60/0x60 ? do_syscall_64+0x67/0x140 ret_from_fork+0x25/0x30 Code: Bad RIP value. RIP: 0xffffffffc17ba640 RSP: ffffb254414dfe78 CR2: ffffffffc17ba640 Note that zilog-rx-i2c-1 should have exited by now, but hasn't due to the missing put in poll(). This code has been replaced completely in kernel v4.16 by a new driver, see commit acaa34bf06e9 ("media: rc: implement zilog transmitter"), and commit f95367a7b758 ("media: staging: remove lirc_zilog driver"). Cc: stable@vger.kernel.org # v4.15- (all up to and including v4.15) Reported-by: Warren Sturm Tested-by: Warren Sturm Signed-off-by: Sean Young Signed-off-by: Greg Kroah-Hartman

Revert "media: lirc_zilog: driver only sends LIRCCODE"

2018-04-24T07:36:39+00:00

[not upstream as the driver is deleted in 4.16 - gregkh] The lirc config documented here https://www.blushingpenguin.com/mark/blog/?p=24 uses raw_codes for sending IR. Each key only has one pulse, which in fact is an index into the haup-ir-blaster.bin file. Changing the driver to LIRCCODE (although more accurate) breaks this configuration. This code has been replaced completely in kernel v4.16 by a new driver, see commit acaa34bf06e9 ("media: rc: implement zilog transmitter"), and commit f95367a7b758 ("media: staging: remove lirc_zilog driver"). This reverts commit 89d8a2cc51d1f29ea24a0b44dde13253141190a0. Fixes: 615cd3fe6ccc ("[media] media: lirc_dev: make better use of file->private_data") Cc: stable@vger.kernel.org # v4.14-v4.15 Reported-by: Warren Sturm Tested-by: Warren Sturm Signed-off-by: Sean Young Signed-off-by: Greg Kroah-Hartman

iwlwifi: add a bunch of new 9000 PCI IDs

2018-04-24T07:36:39+00:00

commit 9e5053ad9d590e095829a8bb07adbbdbd893f0f9 upstream. A lot of new PCI IDs were added for the 9000 series. Add them to the list of supported PCI IDs. Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Luca Coelho Signed-off-by: Greg Kroah-Hartman

iwlwifi: add shared clock PHY config flag for some devices

2018-04-24T07:36:39+00:00

commit 86a2b2043af79deff5cf000c5a08847faa4f2ee0 upstream. Some devices use a shared clock which is very sensitive to variations and cause trouble in some situations. We need to set a bit in the phy configuration to indicate that to the FW. To make this generic, add a extra_phy_config_flags element to the device configuration and OR it into the phy_cfg before sending it to the firmware. And also create a set of configurations for devices that use shared clocks and need this extra bit to be set. Fixes: c62446d2b028 ("iwlwifi: add new 9460 series PCI IDs") Signed-off-by: Luca Coelho Signed-off-by: Greg Kroah-Hartman

net: dsa: Discard frames from unused ports

2018-04-24T07:36:39+00:00

commit fc5f33768cca7144f8d793205b229d46740d183b upstream. The Marvell switches under some conditions will pass a frame to the host with the port being the CPU port. Such frames are invalid, and should be dropped. Not dropping them can result in a crash when incrementing the receive statistics for an invalid port. This has been reworked for 4.14, which does not have the central dsa_master_find_slave() function, so each tag driver needs to check. Reported-by: Chris Healy Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") Signed-off-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

mm/filemap.c: fix NULL pointer in page_cache_tree_insert()

2018-04-24T07:36:39+00:00

commit abc1be13fd113ddef5e2d807a466286b864caed3 upstream. f2fs specifies the __GFP_ZERO flag for allocating some of its pages. Unfortunately, the page cache also uses the mapping's GFP flags for allocating radix tree nodes. It always masked off the __GFP_HIGHMEM flag, and masks off __GFP_ZERO in some paths, but not all. That causes radix tree nodes to be allocated with a NULL list_head, which causes backtraces like: __list_del_entry+0x30/0xd0 list_lru_del+0xac/0x1ac page_cache_tree_insert+0xd8/0x110 The __GFP_DMA and __GFP_DMA32 flags would also be able to sneak through if they are ever used. Fix them all by using GFP_RECLAIM_MASK at the innermost location, and remove it from earlier in the callchain. Link: http://lkml.kernel.org/r/20180411060320.14458-2-willy@infradead.org Fixes: 449dd6984d0e ("mm: keep page cache radix tree nodes in check") Signed-off-by: Matthew Wilcox Reported-by: Chris Fries Debugged-by: Minchan Kim Acked-by: Johannes Weiner Acked-by: Michal Hocko Reviewed-by: Jan Kara Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

autofs: mount point create should honour passed in mode

2018-04-24T07:36:39+00:00

commit 1e6306652ba18723015d1b4967fe9de55f042499 upstream. The autofs file system mkdir inode operation blindly sets the created directory mode to S_IFDIR | 0555, ingoring the passed in mode, which can cause selinux dac_override denials. But the function also checks if the caller is the daemon (as no-one else should be able to do anything here) so there's no point in not honouring the passed in mode, allowing the daemon to set appropriate mode when required. Link: http://lkml.kernel.org/r/152361593601.8051.14014139124905996173.stgit@pluto.themaw.net Signed-off-by: Ian Kent Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Don't leak MNT_INTERNAL away from internal mounts

2018-04-24T07:36:39+00:00

commit 16a34adb9392b2fe4195267475ab5b472e55292c upstream. We want it only for the stuff created by SB_KERNMOUNT mounts, *not* for their copies. As it is, creating a deep stack of bindings of /proc/*/ns/* somewhere in a new namespace and exiting yields a stack overflow. Cc: stable@kernel.org Reported-by: Alexander Aring Bisected-by: Kirill Tkhai Tested-by: Kirill Tkhai Tested-by: Alexander Aring Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman