kernel/linux.git/include, branch v4.4.123

fs: Teach path_connected to handle nfs filesystems with multiple roots.

2018-03-22T08:23:31+00:00

commit 95dd77580ccd66a0da96e6d4696945b8cea39431 upstream. On nfsv2 and nfsv3 the nfs server can export subsets of the same filesystem and report the same filesystem identifier, so that the nfs client can know they are the same filesystem. The subsets can be from disjoint directory trees. The nfsv2 and nfsv3 filesystems provides no way to find the common root of all directory trees exported form the server with the same filesystem identifier. The practical result is that in struct super s_root for nfs s_root is not necessarily the root of the filesystem. The nfs mount code sets s_root to the root of the first subset of the nfs filesystem that the kernel mounts. This effects the dcache invalidation code in generic_shutdown_super currently called shrunk_dcache_for_umount and that code for years has gone through an additional list of dentries that might be dentry trees that need to be freed to accomodate nfs. When I wrote path_connected I did not realize nfs was so special, and it's hueristic for avoiding calling is_subdir can fail. The practical case where this fails is when there is a move of a directory from the subtree exposed by one nfs mount to the subtree exposed by another nfs mount. This move can happen either locally or remotely. With the remote case requiring that the move directory be cached before the move and that after the move someone walks the path to where the move directory now exists and in so doing causes the already cached directory to be moved in the dcache through the magic of d_splice_alias. If someone whose working directory is in the move directory or a subdirectory and now starts calling .. from the initial mount of nfs (where s_root == mnt_root), then path_connected as a heuristic will not bother with the is_subdir check. As s_root really is not the root of the nfs filesystem this heuristic is wrong, and the path may actually not be connected and path_connected can fail. The is_subdir function might be cheap enough that we can call it unconditionally. Verifying that will take some benchmarking and the result may not be the same on all kernels this fix needs to be backported to. So I am avoiding that for now. Filesystems with snapshots such as nilfs and btrfs do something similar. But as the directory tree of the snapshots are disjoint from one another and from the main directory tree rename won't move things between them and this problem will not occur. Cc: stable@vger.kernel.org Reported-by: Al Viro Fixes: 397d425dc26d ("vfs: Test for and handle paths that are unreachable from their mnt_root") Signed-off-by: "Eric W. Biederman" Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

regulator: isl9305: fix array size

2018-03-22T08:23:25+00:00

[ Upstream commit 0c08aaf873174c95e674cf21ffcd041c589d2e5b ] ISL9305_MAX_REGULATOR is the last index used to access the init_data[] array, so we need to add one to this last index to obtain the necessary array size. This fixes the following smatch error: drivers/regulator/isl9305.c:160 isl9305_i2c_probe() error: buffer overflow 'pdata->init_data' 3 <= 3 Fixes: dec38b5ce6a9edb4 ("regulator: isl9305: Add Intersil ISL9305/H driver") Signed-off-by: Vincent Stehlé Cc: Mark Brown Signed-off-by: Mark Brown Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

mm: Fix false-positive VM_BUG_ON() in page_cache_{get,add}_speculative()

2018-03-22T08:23:22+00:00

[ Upstream commit 591a3d7c09fa08baff48ad86c2347dbd28a52753 ] 0day testing by Fengguang Wu triggered this crash while running Trinity: kernel BUG at include/linux/pagemap.h:151! ... CPU: 0 PID: 458 Comm: trinity-c0 Not tainted 4.11.0-rc2-00251-g2947ba0 #1 ... Call Trace: __get_user_pages_fast() get_user_pages_fast() get_futex_key() futex_requeue() do_futex() SyS_futex() do_syscall_64() entry_SYSCALL64_slow_path() It' VM_BUG_ON() due to false-negative in_atomic(). We call page_cache_get_speculative() with disabled local interrupts. It should be atomic enough. So let's check for disabled interrupts in the VM_BUG_ON() condition too, to resolve this. ( This got triggered by the conversion of the x86 GUP code to the generic GUP code. ) Reported-by: Fengguang Wu Signed-off-by: Kirill A. Shutemov Cc: Andrew Morton Cc: Aneesh Kumar K.V Cc: Kirill A. Shutemov Cc: LKP Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170324114709.pcytvyb3d6ajux33@black.fi.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

tcp: sysctl: Fix a race to avoid unexpected 0 window from space

2018-03-22T08:23:22+00:00

[ Upstream commit c48367427a39ea0b85c7cf018fe4256627abfd9e ] Because sysctl_tcp_adv_win_scale could be changed any time, so there is one race in tcp_win_from_space. For example, 1.sysctl_tcp_adv_win_scale<=0 (sysctl_tcp_adv_win_scale is negative now) 2.space>>(-sysctl_tcp_adv_win_scale) (sysctl_tcp_adv_win_scale is postive now) As a result, tcp_win_from_space returns 0. It is unexpected. Certainly if the compiler put the sysctl_tcp_adv_win_scale into one register firstly, then use the register directly, it would be ok. But we could not depend on the compiler behavior. Signed-off-by: Gao Feng Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

usb: quirks: add control message delay for 1b1c:1b20

2018-03-18T10:17:53+00:00

commit cb88a0588717ba6c756cb5972d75766b273a6817 upstream. Corsair Strafe RGB keyboard does not respond to usb control messages sometimes and hence generates timeouts. Commit de3af5bf259d ("usb: quirks: add delay init quirk for Corsair Strafe RGB keyboard") tried to fix those timeouts by adding USB_QUIRK_DELAY_INIT. Unfortunately, even with this quirk timeouts of usb_control_msg() can still be seen, but with a lower frequency (approx. 1 out of 15): [ 29.103520] usb 1-8: string descriptor 0 read error: -110 [ 34.363097] usb 1-8: can't set config #1, error -110 Adding further delays to different locations where usb control messages are issued just moves the timeouts to other locations, e.g.: [ 35.400533] usbhid 1-8:1.0: can't add hid device: -110 [ 35.401014] usbhid: probe of 1-8:1.0 failed with error -110 The only way to reliably avoid those issues is having a pause after each usb control message. In approx. 200 boot cycles no more timeouts were seen. Addionaly, keep USB_QUIRK_DELAY_INIT as it turned out to be necessary to have the delay in hub_port_connect() after hub_port_init(). The overall boot time seems not to be influenced by these additional delays, even on fast machines and lightweight distributions. Fixes: de3af5bf259d ("usb: quirks: add delay init quirk for Corsair Strafe RGB keyboard") Cc: stable@vger.kernel.org Signed-off-by: Danilo Krummrich Signed-off-by: Greg Kroah-Hartman

netfilter: x_tables: pack percpu counter allocations

2018-03-18T10:17:52+00:00

commit ae0ac0ed6fcf5af3be0f63eb935f483f44a402d2 upstream. instead of allocating each xt_counter individually, allocate 4k chunks and then use these for counter allocation requests. This should speed up rule evaluation by increasing data locality, also speeds up ruleset loading because we reduce calls to the percpu allocator. As Eric points out we can't use PAGE_SIZE, page_allocator would fail on arches with 64k page size. Suggested-by: Eric Dumazet Signed-off-by: Florian Westphal Acked-by: Eric Dumazet Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: x_tables: pass xt_counters struct to counter allocator

2018-03-18T10:17:52+00:00

commit f28e15bacedd444608e25421c72eb2cf4527c9ca upstream. Keeps some noise away from a followup patch. Signed-off-by: Florian Westphal Acked-by: Eric Dumazet Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: x_tables: pass xt_counters struct instead of packet counter

2018-03-18T10:17:52+00:00

commit 4d31eef5176df06f218201bc9c0ce40babb41660 upstream. On SMP we overload the packet counter (unsigned long) to contain percpu offset. Hide this from callers and pass xt_counters address instead. Preparation patch to allocate the percpu counters in page-sized batch chunks. Signed-off-by: Florian Westphal Acked-by: Eric Dumazet Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

nospec: Include dependency

2018-03-18T10:17:50+00:00

commit eb6174f6d1be16b19cfa43dac296bfed003ce1a6 upstream. The nospec.h header expects the per-architecture header file to optionally define array_index_mask_nospec(). Include that dependency to prevent inadvertent fallback to the default array_index_mask_nospec() implementation. The default implementation may not provide a full mitigation on architectures that perform data value speculation. Reported-by: Christian Borntraeger Signed-off-by: Dan Williams Cc: Andy Lutomirski Cc: Arjan van de Ven Cc: Borislav Petkov Cc: Dave Hansen Cc: David Woodhouse Cc: Greg Kroah-Hartman Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/151881605404.17395.1341935530792574707.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

drm: Allow determining if current task is output poll worker

2018-03-18T10:17:48+00:00

commit 25c058ccaf2ebbc3e250ec1e199e161f91fe27d4 upstream. Introduce a helper to determine if the current task is an output poll worker. This allows us to fix a long-standing deadlock in several DRM drivers wherein the ->runtime_suspend callback waits for the output poll worker to finish and the worker in turn calls a ->detect callback which waits for runtime suspend to finish. The ->detect callback is invoked from multiple call sites and waiting for runtime suspend to finish is the correct thing to do except if it's executing in the context of the worker. v2: Expand kerneldoc to specifically mention deadlock between output poll worker and autosuspend worker as use case. (Lyude) Cc: Dave Airlie Cc: Ben Skeggs Cc: Alex Deucher Reviewed-by: Lyude Paul Signed-off-by: Lukas Wunner Link: https://patchwork.freedesktop.org/patch/msgid/3549ce32e7f1467102e70d3e9cbf70c46bfe108e.1518593424.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman