- 15 Feb, 2016 8 commits
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xuejiufei authored
commit c95a5180 upstream. When recovery master down, dlm_do_local_recovery_cleanup() only remove the $RECOVERY lock owned by dead node, but do not clear the refmap bit. Which will make umount thread falling in dead loop migrating $RECOVERY to the dead node. Signed-off-by:
xuejiufei <xuejiufei@huawei.com> Reviewed-by:
Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
Jiri Slaby <jslaby@suse.cz>
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xuejiufei authored
commit bef5502d upstream. We have found that migration source will trigger a BUG that the refcount of mle is already zero before put when the target is down during migration. The situation is as follows: dlm_migrate_lockres dlm_add_migration_mle dlm_mark_lockres_migrating dlm_get_mle_inuse <<<<<< Now the refcount of the mle is 2. dlm_send_one_lockres and wait for the target to become the new master. <<<<<< o2hb detect the target down and clean the migration mle. Now the refcount is 1. dlm_migrate_lockres woken, and put the mle twice when found the target goes down which trigger the BUG with the following message: "ERROR: bad mle: ". Signed-off-by:
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Richard Weinberger authored
commit 9d8a7652 upstream. sigsuspend() is nowhere used except in signal.c itself, so we can mark it static do not pollute the global namespace. But this patch is more than a boring cleanup patch, it fixes a real issue on UserModeLinux. UML has a special console driver to display ttys using xterm, or other terminal emulators, on the host side. Vegard reported that sometimes UML is unable to spawn a xterm and he's facing the following warning: WARNING: CPU: 0 PID: 908 at include/linux/thread_info.h:128 sigsuspend+0xab/0xc0() It turned out that this warning makes absolutely no sense as the UML xterm code calls sigsuspend() on the host side, at least it tries. But as the kernel itself offers a sigsuspend() symbol the linker choose this one instead of the glibc wrapper. Interestingly this code used to work since ever but always blocked signals on the wrong side. Some recent kernel change made the WARN_ON() trigger and uncovered the bug. It is a wonderful example of how much works by chance on computers. :-) Fixes: 68f3f16d ("new helper: sigsuspend()") Signed-off-by:
Richard Weinberger <richard@nod.at> Reported-by:
Vegard Nossum <vegard.nossum@oracle.com> Tested-by:
Oleg Nesterov <oleg@redhat.com> Signed-off-by:
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OGAWA Hirofumi authored
commit 928a4771 upstream. For the root directory, . and .. are faked (using dir_emit_dots()) and ctx->pos is reset from 2 to 0. A corrupted root directory could cause fat_get_entry() to fail, but ->iterate() (fat_readdir()) reports progress to the VFS (with ctx->pos rewound to 0), so any following calls to ->iterate() continue to return the same entries again and again. The result is that userspace will never see the end of the directory, causing e.g. 'ls' to hang in a getdents() loop. [hirofumi@mail.parknet.co.jp: cleanup and make sure to correct fake_offset] Reported-by:
Richard Weinberger <richard.weinberger@gmail.com> Signed-off-by:
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by:
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Arnd Bergmann authored
commit 92792e48 upstream. Recent gcc versions warn about reading from a negative offset of an on-stack array: drivers/remoteproc/remoteproc_debugfs.c: In function 'rproc_recovery_write': drivers/remoteproc/remoteproc_debugfs.c:167:9: warning: 'buf[4294967295u]' may be used uninitialized in this function [-Wmaybe-uninitialized] I don't see anything in sys_write() that prevents us from being called with a zero 'count' argument, so we should add an extra check in rproc_recovery_write() to prevent the access and avoid the warning. Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Fixes: 2e37abb8 ("remoteproc: create a 'recovery' debugfs entry") Signed-off-by:
Ohad Ben-Cohen <ohad@wizery.com> Signed-off-by:
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Oleg Nesterov authored
commit 54708d28 upstream. The commit 96d0df79 ("proc: make proc_fd_permission() thread-friendly") fixed the access to /proc/self/fd from sub-threads, but introduced another problem: a sub-thread can't access /proc/<tid>/fd/ or /proc/thread-self/fd if generic_permission() fails. Change proc_fd_permission() to check same_thread_group(pid_task(), current). Fixes: 96d0df79 ("proc: make proc_fd_permission() thread-friendly") Reported-by:
"Jin, Yihua" <yihua.jin@intel.com> Signed-off-by:
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Jiri Slaby authored
This reverts commit e1f20b83, upstream commit 8f1eb487. This commit fixes 702e5bc6 ("ocfs2: use generic posix ACL infrastructure"), which is only in 3.14. So this commit should have never been applied to 3.12 and it can cause sgid inheritance issues. Signed-off-by:
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Ben Hutchings authored
Quoting the RHEL advisory: > It was found that the fix for CVE-2015-1805 incorrectly kept buffer > offset and buffer length in sync on a failed atomic read, potentially > resulting in a pipe buffer state corruption. A local, unprivileged user > could use this flaw to crash the system or leak kernel memory to user > space. (CVE-2016-0774, Moderate) The same flawed fix was applied to stable branches from 2.6.32.y to 3.14.y inclusive, and I was able to reproduce the issue on 3.2.y. We need to give pipe_iov_copy_to_user() a separate offset variable and only update the buffer offset if it succeeds. References: https://rhn.redhat.com/errata/RHSA-2016-0103.htmlSigned-off-by:
Ben Hutchings <ben@decadent.org.uk> Signed-off-by:
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- 12 Feb, 2016 32 commits
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J. Bruce Fields authored
commit 7632e465 upstream. Every hashed dentry is either hashed in the dentry_hashtable, or a superblock's s_anon list. __d_drop() assumes it can determine which is the case by checking DCACHE_DISCONNECTED; this is not true. It is true that when DCACHE_DISCONNECTED is cleared, the dentry is not only hashed on dentry_hashtable, but is fully connected to its parents back to the root. But the converse is *not* true: fs/exportfs/expfs.c:reconnect_path() attempts to connect a directory (found by filehandle lookup) back to root by ascending to parents and performing lookups one at a time. It does not clear DCACHE_DISCONNECTED until it's done, and that is not at all an atomic process. In particular, it is possible for DCACHE_DISCONNECTED to be set on a dentry which is hashed on the dentry_hashtable. Instead, use IS_ROOT() to check which hash chain a dentry is on. This *does* work: Dentries are hashed only by: - d_obtain_alias, which adds an IS_ROOT() dentry to sb_anon. - __d_rehash, called by _d_rehash: hashes to the dentry's parent, and all callers of _d_rehash appear to have d_parent set to a "real" parent. - __d_rehash, called by __d_move: rehashes the moved dentry to hash chain determined by target, and assigns target's d_parent to its d_parent, before dropping the dentry's d_lock. Therefore I believe it's safe for a holder of a dentry's d_lock to assume that it is hashed on sb_anon if and only if IS_ROOT(dentry) is true. I believe the incorrect assumption about DCACHE_DISCONNECTED was originally introduced by ceb5bdc2 "fs: dcache per-bucket dcache hash locking". Also add a comment while we're here. Cc: Nick Piggin <npiggin@kernel.dk> Acked-by:
Christoph Hellwig <hch@infradead.org> Reviewed-by:
NeilBrown <neilb@suse.de> Signed-off-by:
J. Bruce Fields <bfields@redhat.com> Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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Jiri Slaby authored
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Nikolay Borisov authored
commit 18d03e8c upstream. When a thin pool is being destroyed delayed work items are cancelled using cancel_delayed_work(), which doesn't guarantee that on return the delayed item isn't running. This can cause the work item to requeue itself on an already destroyed workqueue. Fix this by using cancel_delayed_work_sync() which guarantees that on return the work item is not running anymore. Fixes: 905e51b3 ("dm thin: commit outstanding data every second") Fixes: 85ad643b ("dm thin: add timeout to stop out-of-data-space mode holding IO forever") Signed-off-by:
Nikolay Borisov <kernel@kyup.com> Signed-off-by:
Mike Snitzer <snitzer@redhat.com> Cc: Nikolay Borisov <kernel@kyup.com> Signed-off-by:
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Ioan-Adrian Ratiu authored
commit e470127e upstream. The critical section protected by usbhid->lock in hid_ctrl() is too big and because of this it causes a recursive deadlock. "Too big" means the case statement and the call to hid_input_report() do not need to be protected by the spinlock (no URB operations are done inside them). The deadlock happens because in certain rare cases drivers try to grab the lock while handling the ctrl irq which grabs the lock before them as described above. For example newer wacom tablets like 056a:033c try to reschedule proximity reads from wacom_intuos_schedule_prox_event() calling hid_hw_request() -> usbhid_request() -> usbhid_submit_report() which tries to grab the usbhid lock already held by hid_ctrl(). There are two ways to get out of this deadlock: 1. Make the drivers work "around" the ctrl critical region, in the wacom case for ex. by delaying the scheduling of the proximity read request itself to a workqueue. 2. Shrink the critical region so the usbhid lock protects only the instructions which modify usbhid state, calling hid_input_report() with the spinlock unlocked, allowing the device driver to grab the lock first, finish and then grab the lock afterwards in hid_ctrl(). This patch implements the 2nd solution. Signed-off-by:
Ioan-Adrian Ratiu <adi@adirat.com> Signed-off-by:
Jiri Kosina <jkosina@suse.cz> Signed-off-by:
Jason Gerecke <jason.gerecke@wacom.com> Signed-off-by:
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Seth Jennings authored
commit 26bbe7ef upstream. Commit bdee237c ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems") and 982792c7 ("x86, mm: probe memory block size for generic x86 64bit") introduced large block sizes for x86. This made it possible to have multiple sections per memory block where previously, there was a only every one section per block. Since blocks consist of contiguous ranges of section, there can be holes in the blocks where sections are not present. If one attempts to offline such a block, a crash occurs since the code is not designed to deal with this. This patch is a quick fix to gaurd against the crash by not allowing blocks with non-present sections to be offlined. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=107781Signed-off-by:
Seth Jennings <sjennings@variantweb.net> Reported-by:
Andrew Banman <abanman@sgi.com> Cc: Daniel J Blueman <daniel@numascale.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Greg KH <greg@kroah.com> Cc: Russ Anderson <rja@sgi.com> Signed-off-by:
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Mike Snitzer authored
commit 30ce6e1c upstream. The block allocated at the start of btree_split_sibling() is never released if later insert_at() fails. Fix this by releasing the previously allocated bufio block using unlock_block(). Reported-by:
Mikulas Patocka <mpatocka@redhat.com> Signed-off-by:
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Herbert Xu authored
commit 4afa5f96 upstream. The hash_accept call fails to work on sockets that have not received any data. For some algorithm implementations it may cause crashes. This patch fixes this by ensuring that we only export and import on sockets that have received data. Reported-by:
Harsh Jain <harshjain.prof@gmail.com> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Tested-by:
Stephan Mueller <smueller@chronox.de> Signed-off-by:
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libin authored
commit c84da8b9 upstream. In nop_mcount, shdr->sh_offset and welp->r_offset should handle endianness properly, otherwise it will trigger Segmentation fault if the recordmcount main and file.o have different endianness. Link: http://lkml.kernel.org/r/563806C7.7070606@huawei.comSigned-off-by:
Li Bin <huawei.libin@huawei.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Greg Kroah-Hartman authored
In the backport of 1eaf35e4, the call to usb_disabled() was too late, after we had already done some allocation. Move that call to the top of the function instead, making the logic match what is intended and is in the original patch. Reported-by:
Luis Henriques <luis.henriques@canonical.com> Signed-off-by:
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Tejun Heo authored
commit 041bd12e upstream. This reverts commit 874bbfe6. Workqueue used to implicity guarantee that work items queued without explicit CPU specified are put on the local CPU. Recent changes in timer broke the guarantee and led to vmstat breakage which was fixed by 176bed1d ("vmstat: explicitly schedule per-cpu work on the CPU we need it to run on"). vmstat is the most likely to expose the issue and it's quite possible that there are other similar problems which are a lot more difficult to trigger. As a preventive measure, 874bbfe6 ("workqueue: make sure delayed work run in local cpu") was applied to restore the local CPU guarnatee. Unfortunately, the change exposed a bug in timer code which got fixed by 22b886dd ("timers: Use proper base migration in add_timer_on()"). Due to code restructuring, the commit couldn't be backported beyond certain point and stable kernels which only had 874bbfe6 started crashing. The local CPU guarantee was accidental more than anything else and we want to get rid of it anyway. As, with the vmstat case fixed, 874bbfe6 is causing more problems than it's fixing, it has been decided to take the chance and officially break the guarantee by reverting the commit. A debug feature will be added to force foreign CPU assignment to expose cases relying on the guarantee and fixes for the individual cases will be backported to stable as necessary. Signed-off-by:
Tejun Heo <tj@kernel.org> Fixes: 874bbfe6 ("workqueue: make sure delayed work run in local cpu") Link: http://lkml.kernel.org/g/20160120211926.GJ10810@quack.suse.cz Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: Daniel Bilik <daniel.bilik@neosystem.cz> Cc: Jan Kara <jack@suse.cz> Cc: Shaohua Li <shli@fb.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Daniel Bilik <daniel.bilik@neosystem.cz> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by:
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Linus Torvalds authored
commit 176bed1d upstream. The vmstat code uses "schedule_delayed_work_on()" to do the initial startup of the delayed work on the right CPU, but then once it was started it would use the non-cpu-specific "schedule_delayed_work()" to re-schedule it on that CPU. That just happened to schedule it on the same CPU historically (well, in almost all situations), but the code _requires_ this work to be per-cpu, and should say so explicitly rather than depend on the non-cpu-specific scheduling to schedule on the current CPU. The timer code is being changed to not be as single-minded in always running things on the calling CPU. See also commit 874bbfe6 ("workqueue: make sure delayed work run in local cpu") that for now maintains the local CPU guarantees just in case there are other broken users that depended on the accidental behavior. js: 3.12 backport Cc: Christoph Lameter <cl@linux.com> Cc: Tejun Heo <tj@kernel.org> Cc: Mike Galbraith <mgalbraith@suse.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by:
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Andrew Morton authored
commit 04ea1e91 upstream. openrisc-allnoconfig: kernel/uid16.c: In function 'SYSC_setgroups16': kernel/uid16.c:184:2: error: implicit declaration of function 'groups_alloc' kernel/uid16.c:184:13: warning: assignment makes pointer from integer without a cast openrisc shouldn't be setting CONFIG_UID16 when CONFIG_MULTIUSER=n. Fixes: 2813893f ("kernel: conditionally support non-root users, groups and capabilities") Reported-by:
Fengguang Wu <fengguang.wu@gmail.com> Cc: Iulia Manda <iulia.manda21@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Signed-off-by:
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Jiri Slaby authored
On 3.12, with gcc-6, I see a lot of: arch/x86/include/asm/vvar.h:33:28: warning: ‘vvaraddr_jiffies’ defined but not used [-Wunused-const-variable] static type const * const vvaraddr_ ## name = \ ^ arch/x86/include/asm/vvar.h:46:1: note: in expansion of macro ‘DECLARE_VVAR’ DECLARE_VVAR(0, volatile unsigned long, jiffies) ^~~~~~~~~~~~ In upstream, this is fixed by ef721987 (x86, vdso: Introduce VVAR marco for vdso32) and f40c3300 (x86, vdso: Move the vvar and hpet mappings next to the 64-bit vDSO). But this is not applicable to stable. So mark the vvar declaration as __maybe_unused and be done with it. This will generate it to the code only if it is used. I.e. the same as with gcc < 6. Signed-off-by: -
Joe Perches authored
commit cb984d10 upstream. As gcc major version numbers are going to advance rather rapidly in the future, there's no real value in separate files for each compiler version. Deduplicate some of the macros #defined in each file too. Neaten comments using normal kernel commenting style. Signed-off-by:
Joe Perches <joe@perches.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Sasha Levin <levinsasha928@gmail.com> Cc: Anton Blanchard <anton@samba.org> Cc: Alan Modra <amodra@gmail.com> Signed-off-by:
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Steven Noonan authored
commit 5631b8fb upstream. The bug referenced by the comment in this commit was not completely fixed in GCC 4.8.2, as I mentioned in a thread back in February: https://lkml.org/lkml/2014/2/12/797 The conclusion at that time was to make the quirk unconditional until the bug could be found and fixed in GCC. Unfortunately, when I submitted the patch (commit a9f18034) I left a comment in that claimed the bug was fixed in GCC 4.8.2+. This comment is inaccurate, and should be removed. Signed-off-by:
Steven Noonan <steven@uplinklabs.net> Signed-off-by:
Ingo Molnar <mingo@kernel.org> Cc: Jakub Jelinek <jakub@redhat.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1414274982-14040-1-git-send-email-steven@uplinklabs.net Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Yang Shi authored
commit 92e788b7 upstream. As previously reported, some userspace applications depend on bogomips showed by /proc/cpuinfo. Although there is much less legacy impact on aarch64 than arm, it does break libvirt. This patch reverts commit 326b16db ("arm64: delay: don't bother reporting bogomips in /proc/cpuinfo"), but with some tweak due to context change and without the pr_info(). Fixes: 326b16db ("arm64: delay: don't bother reporting bogomips in /proc/cpuinfo") Signed-off-by:
Yang Shi <yang.shi@linaro.org> Acked-by:
Will Deacon <will.deacon@arm.com> Signed-off-by:
Catalin Marinas <catalin.marinas@arm.com> Signed-off-by:
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Guenter Roeck authored
commit c86576ea upstream. mn10300 builds fail with fs/stat.c: In function 'cp_old_stat': fs/stat.c:163:2: error: 'old_uid_t' undeclared ipc/util.c: In function 'ipc64_perm_to_ipc_perm': ipc/util.c:540:2: error: 'old_uid_t' undeclared Select CONFIG_HAVE_UID16 and remove local definition of CONFIG_UID16 to fix the problem. Fixes: fbc416ff ("arm64: fix building without CONFIG_UID16") Cc: Arnd Bergmann <arnd@arndb.de> Acked-by:
Acked-by: David Howells <dhowells@redhat.com> Signed-off-by:
Guenter Roeck <linux@roeck-us.net> Signed-off-by:
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Richard Purdie authored
commit 79b568b9 upstream. hid_connect adds various strings to the buffer but they're all conditional. You can find circumstances where nothing would be written to it but the kernel will still print the supposedly empty buffer with printk. This leads to corruption on the console/in the logs. Ensure buf is initialized to an empty string. Signed-off-by:
Richard Purdie <richard.purdie@linuxfoundation.org> [dvhart: Initialize string to "" rather than assign buf[0] = NULL;] Cc: Jiri Kosina <jikos@kernel.org> Cc: linux-input@vger.kernel.org Signed-off-by:
Darren Hart <dvhart@linux.intel.com> Signed-off-by:
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Mikulas Patocka authored
commit e46e31a3 upstream. When using the Promise TX2+ SATA controller on PA-RISC, the system often crashes with kernel panic, for example just writing data with the dd utility will make it crash. Kernel panic - not syncing: drivers/parisc/sba_iommu.c: I/O MMU @ 000000000000a000 is out of mapping resources CPU: 0 PID: 18442 Comm: mkspadfs Not tainted 4.4.0-rc2 #2 Backtrace: [<000000004021497c>] show_stack+0x14/0x20 [<0000000040410bf0>] dump_stack+0x88/0x100 [<000000004023978c>] panic+0x124/0x360 [<0000000040452c18>] sba_alloc_range+0x698/0x6a0 [<0000000040453150>] sba_map_sg+0x260/0x5b8 [<000000000c18dbb4>] ata_qc_issue+0x264/0x4a8 [libata] [<000000000c19535c>] ata_scsi_translate+0xe4/0x220 [libata] [<000000000c19a93c>] ata_scsi_queuecmd+0xbc/0x320 [libata] [<0000000040499bbc>] scsi_dispatch_cmd+0xfc/0x130 [<000000004049da34>] scsi_request_fn+0x6e4/0x970 [<00000000403e95a8>] __blk_run_queue+0x40/0x60 [<00000000403e9d8c>] blk_run_queue+0x3c/0x68 [<000000004049a534>] scsi_run_queue+0x2a4/0x360 [<000000004049be68>] scsi_end_request+0x1a8/0x238 [<000000004049de84>] scsi_io_completion+0xfc/0x688 [<0000000040493c74>] scsi_finish_command+0x17c/0x1d0 The cause of the crash is not exhaustion of the IOMMU space, there is plenty of free pages. The function sba_alloc_range is called with size 0x11000, thus the pages_needed variable is 0x11. The function sba_search_bitmap is called with bits_wanted 0x11 and boundary size is 0x10 (because dma_get_seg_boundary(dev) returns 0xffff). The function sba_search_bitmap attempts to allocate 17 pages that must not cross 16-page boundary - it can't satisfy this requirement (iommu_is_span_boundary always returns true) and fails even if there are many free entries in the IOMMU space. How did it happen that we try to allocate 17 pages that don't cross 16-page boundary? The cause is in the function iommu_coalesce_chunks. This function tries to coalesce adjacent entries in the scatterlist. The function does several checks if it may coalesce one entry with the next, one of those checks is this: if (startsg->length + dma_len > max_seg_size) break; When it finishes coalescing adjacent entries, it allocates the mapping: sg_dma_len(contig_sg) = dma_len; dma_len = ALIGN(dma_len + dma_offset, IOVP_SIZE); sg_dma_address(contig_sg) = PIDE_FLAG | (iommu_alloc_range(ioc, dev, dma_len) << IOVP_SHIFT) | dma_offset; It is possible that (startsg->length + dma_len > max_seg_size) is false (we are just near the 0x10000 max_seg_size boundary), so the funcion decides to coalesce this entry with the next entry. When the coalescing succeeds, the function performs dma_len = ALIGN(dma_len + dma_offset, IOVP_SIZE); And now, because of non-zero dma_offset, dma_len is greater than 0x10000. iommu_alloc_range (a pointer to sba_alloc_range) is called and it attempts to allocate 17 pages for a device that must not cross 16-page boundary. To fix the bug, we must make sure that dma_len after addition of dma_offset and alignment doesn't cross the segment boundary. I.e. change if (startsg->length + dma_len > max_seg_size) break; to if (ALIGN(dma_len + dma_offset + startsg->length, IOVP_SIZE) > max_seg_size) break; This patch makes this change (it precalculates max_seg_boundary at the beginning of the function iommu_coalesce_chunks). I also added a check that the mapping length doesn't exceed dma_get_seg_boundary(dev) (it is not needed for Promise TX2+ SATA, but it may be needed for other devices that have dma_get_seg_boundary lower than dma_get_max_seg_size). Signed-off-by:
Helge Deller <deller@gmx.de> Signed-off-by:
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Will Deacon authored
commit 32d63978 upstream. In paging_init, we allocate the zero page, memset it to zero and then point TTBR0 to it in order to avoid speculative fetches through the identity mapping. In order to guarantee that the freshly zeroed page is indeed visible to the page table walker, we need to execute a dsb instruction prior to writing the TTBR. Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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John Blackwood authored
commit 5db4fd8c upstream. Make sure to clear out any ptrace singlestep state when a ptrace(2) PTRACE_DETACH call is made on arm64 systems. Otherwise, the previously ptraced task will die off with a SIGTRAP signal if the debugger just previously singlestepped the ptraced task. Signed-off-by:
John Blackwood <john.blackwood@ccur.com> [will: added comment to justify why this is in the arch code] Signed-off-by:
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Arnd Bergmann authored
commit fbc416ff upstream. As reported by Michal Simek, building an ARM64 kernel with CONFIG_UID16 disabled currently fails because the system call table still needs to reference the individual function entry points that are provided by kernel/sys_ni.c in this case, and the declarations are hidden inside of #ifdef CONFIG_UID16: arch/arm64/include/asm/unistd32.h:57:8: error: 'sys_lchown16' undeclared here (not in a function) __SYSCALL(__NR_lchown, sys_lchown16) I believe this problem only exists on ARM64, because older architectures tend to not need declarations when their system call table is built in assembly code, while newer architectures tend to not need UID16 support. ARM64 only uses these system calls for compatibility with 32-bit ARM binaries. This changes the CONFIG_UID16 check into CONFIG_HAVE_UID16, which is set unconditionally on ARM64 with CONFIG_COMPAT, so we see the declarations whenever we need them, but otherwise the behavior is unchanged. Fixes: af1839eb ("Kconfig: clean up the long arch list for the UID16 config option") Signed-off-by:
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Marc Zyngier authored
commit c0f09634 upstream. When running a 32bit guest under a 64bit hypervisor, the ARMv8 architecture defines a mapping of the 32bit registers in the 64bit space. This includes banked registers that are being demultiplexed over the 64bit ones. On exceptions caused by an operation involving a 32bit register, the HW exposes the register number in the ESR_EL2 register. It was so far understood that SW had to distinguish between AArch32 and AArch64 accesses (based on the current AArch32 mode and register number). It turns out that I misinterpreted the ARM ARM, and the clue is in D1.20.1: "For some exceptions, the exception syndrome given in the ESR_ELx identifies one or more register numbers from the issued instruction that generated the exception. Where the exception is taken from an Exception level using AArch32 these register numbers give the AArch64 view of the register." Which means that the HW is already giving us the translated version, and that we shouldn't try to interpret it at all (for example, doing an MMIO operation from the IRQ mode using the LR register leads to very unexpected behaviours). The fix is thus not to perform a call to vcpu_reg32() at all from vcpu_reg(), and use whatever register number is supplied directly. The only case we need to find out about the mapping is when we actively generate a register access, which only occurs when injecting a fault in a guest. Reviewed-by:
Robin Murphy <robin.murphy@arm.com> Signed-off-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by:
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Ulrich Weigand authored
commit 2e50c4be upstream. If a text section starts out with a data blob before the first function start label, disassembly parsing doing in recordmcount.pl gets confused on powerpc, leading to creation of corrupted module objects. This was not a problem so far since the compiler would never create such text sections. However, this has changed with a recent change in GCC 6 to support distances of > 2GB between a function and its assoicated TOC in the ELFv2 ABI, exposing this problem. There is already code in recordmcount.pl to handle such data blobs on the sparc64 platform. This patch uses the same method to handle those on powerpc as well. Acked-by:
Ulrich Weigand <ulrich.weigand@de.ibm.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Boqun Feng authored
commit 81d7a329 upstream. According to memory-barriers.txt, xchg*, cmpxchg* and their atomic_ versions all need to be fully ordered, however they are now just RELEASE+ACQUIRE, which are not fully ordered. So also replace PPC_RELEASE_BARRIER and PPC_ACQUIRE_BARRIER with PPC_ATOMIC_ENTRY_BARRIER and PPC_ATOMIC_EXIT_BARRIER in __{cmp,}xchg_{u32,u64} respectively to guarantee fully ordered semantics of atomic{,64}_{cmp,}xchg() and {cmp,}xchg(), as a complement of commit b97021f8 ("powerpc: Fix atomic_xxx_return barrier semantics") This patch depends on patch "powerpc: Make value-returning atomics fully ordered" for PPC_ATOMIC_ENTRY_BARRIER definition. Signed-off-by:
Boqun Feng <boqun.feng@gmail.com> Reviewed-by:
Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by:
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Boqun Feng authored
commit 49e9cf3f upstream. According to memory-barriers.txt: > Any atomic operation that modifies some state in memory and returns > information about the state (old or new) implies an SMP-conditional > general memory barrier (smp_mb()) on each side of the actual > operation ... Which mean these operations should be fully ordered. However on PPC, PPC_ATOMIC_ENTRY_BARRIER is the barrier before the actual operation, which is currently "lwsync" if SMP=y. The leading "lwsync" can not guarantee fully ordered atomics, according to Paul Mckenney: https://lkml.org/lkml/2015/10/14/970 To fix this, we define PPC_ATOMIC_ENTRY_BARRIER as "sync" to guarantee the fully-ordered semantics. This also makes futex atomics fully ordered, which can avoid possible memory ordering problems if userspace code relies on futex system call for fully ordered semantics. Fixes: b97021f8 ("powerpc: Fix atomic_xxx_return barrier semantics") Signed-off-by:
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Michael Neuling authored
commit d2b9d2a5 upstream. Currently we allow both the MSR T and S bits to be set by userspace on a signal return. Unfortunately this is a reserved configuration and will cause a TM Bad Thing exception if attempted (via rfid). This patch checks for this case in both the 32 and 64 bit signals code. If both T and S are set, we mark the context as invalid. Found using a syscall fuzzer. Fixes: 2b0a576d ("powerpc: Add new transactional memory state to the signal context") Signed-off-by:
Michael Neuling <mikey@neuling.org> Signed-off-by:
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Dan Streetman authored
[ Upstream commit a8a572a6 ] Remove the dst_entries_init/destroy calls for xfrm4 and xfrm6 dst_ops templates; their dst_entries counters will never be used. Move the xfrm dst_ops initialization from the common xfrm/xfrm_policy.c to xfrm4/xfrm4_policy.c and xfrm6/xfrm6_policy.c, and call dst_entries_init and dst_entries_destroy for each net namespace. The ipv4 and ipv6 xfrms each create dst_ops template, and perform dst_entries_init on the templates. The template values are copied to each net namespace's xfrm.xfrm*_dst_ops. The problem there is the dst_ops pcpuc_entries field is a percpu counter and cannot be used correctly by simply copying it to another object. The result of this is a very subtle bug; changes to the dst entries counter from one net namespace may sometimes get applied to a different net namespace dst entries counter. This is because of how the percpu counter works; it has a main count field as well as a pointer to the percpu variables. Each net namespace maintains its own main count variable, but all point to one set of percpu variables. When any net namespace happens to change one of the percpu variables to outside its small batch range, its count is moved to the net namespace's main count variable. So with multiple net namespaces operating concurrently, the dst_ops entries counter can stray from the actual value that it should be; if counts are consistently moved from one net namespace to another (which my testing showed is likely), then one net namespace winds up with a negative dst_ops count while another winds up with a continually increasing count, eventually reaching its gc_thresh limit, which causes all new traffic on the net namespace to fail with -ENOBUFS. Signed-off-by:
Dan Streetman <dan.streetman@canonical.com> Signed-off-by:
Dan Streetman <ddstreet@ieee.org> Signed-off-by:
Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by:
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Ido Schimmel authored
[ Upstream commit 60a6531b ] We can't be within an RCU read-side critical section when deleting VLANs, as underlying drivers might sleep during the hardware operation. Therefore, replace the RCU critical section with a mutex. This is consistent with team_vlan_rx_add_vid. Fixes: 3d249d4c ("net: introduce ethernet teaming device") Acked-by:
Jiri Pirko <jiri@mellanox.com> Signed-off-by:
Ido Schimmel <idosch@mellanox.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
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Eric Dumazet authored
[ Upstream commit 34ae6a1a ] When a tunnel decapsulates the outer header, it has to comply with RFC 6080 and eventually propagate CE mark into inner header. It turns out IP6_ECN_set_ce() does not correctly update skb->csum for CHECKSUM_COMPLETE packets, triggering infamous "hw csum failure" messages and stack traces. Signed-off-by:
Eric Dumazet <edumazet@google.com> Acked-by:
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Eric Dumazet authored
[ Upstream commit 7aaed57c ] Ivaylo Dimitrov reported a regression caused by commit 7866a621 ("dev: add per net_device packet type chains"). skb->dev becomes NULL and we crash in __netif_receive_skb_core(). Before above commit, different kind of bugs or corruptions could happen without major crash. But the root cause is that phonet_rcv() can queue skb without checking if skb is shared or not. Many thanks to Ivaylo Dimitrov for his help, diagnosis and tests. Reported-by:
Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> Tested-by:
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Neal Cardwell authored
[ Upstream commit 83d15e70 ] For tcp_yeah, use an ssthresh floor of 2, the same floor used by Reno and CUBIC, per RFC 5681 (equation 4). tcp_yeah_ssthresh() was sometimes returning a 0 or negative ssthresh value if the intended reduction is as big or bigger than the current cwnd. Congestion control modules should never return a zero or negative ssthresh. A zero ssthresh generally results in a zero cwnd, causing the connection to stall. A negative ssthresh value will be interpreted as a u32 and will set a target cwnd for PRR near 4 billion. Oleksandr Natalenko reported that a system using tcp_yeah with ECN could see a warning about a prior_cwnd of 0 in tcp_cwnd_reduction(). Testing verified that this was due to tcp_yeah_ssthresh() misbehaving in this way. Reported-by:
Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by:
Neal Cardwell <ncardwell@google.com> Signed-off-by:
Yuchung Cheng <ycheng@google.com> Signed-off-by:
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