- 21 Apr, 2017 25 commits
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Benjamin Herrenschmidt authored
commit 7ed23e1b upstream. On Power8 & Power9 the early CPU inititialisation in __init_HFSCR() turns on HFSCR[TM] (Hypervisor Facility Status and Control Register [Transactional Memory]), but that doesn't take into account that TM might be disabled by CPU features, or disabled by the kernel being built with CONFIG_PPC_TRANSACTIONAL_MEM=n. So later in boot, when we have setup the CPU features, clear HSCR[TM] if the TM CPU feature has been disabled. We use CPU_FTR_TM_COMP to account for the CONFIG_PPC_TRANSACTIONAL_MEM=n case. Without this a KVM guest might try use TM, even if told not to, and cause an oops in the host kernel. Typically the oops is seen in __kvmppc_vcore_entry() and may or may not be fatal to the host, but is always bad news. In practice all shipping CPU revisions do support TM, and all host kernels we are aware of build with TM support enabled, so no one should actually be able to hit this in the wild. Fixes: 2a3563b0 ("powerpc: Setup in HFSCR for POWER8") Cc: stable@vger.kernel.org # v3.10+ Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by:
Sam Bobroff <sam.bobroff@au1.ibm.com> [mpe: Rewrite change log with input from Sam, add Fixes/stable] Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> [sb: Backported to linux-4.4.y: adjusted context] Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Minchan Kim authored
commit d72e9a7a upstream. The copy_page is optimized memcpy for page-alinged address. If it is used with non-page aligned address, it can corrupt memory which means system corruption. With zram, it can happen with 1. 64K architecture 2. partial IO 3. slub debug Partial IO need to allocate a page and zram allocates it via kmalloc. With slub debug, kmalloc(PAGE_SIZE) doesn't return page-size aligned address. And finally, copy_page(mem, cmem) corrupts memory. So, this patch changes it to memcpy. Actuaully, we don't need to change zram_bvec_write part because zsmalloc returns page-aligned address in case of PAGE_SIZE class but it's not good to rely on the internal of zsmalloc. Note: When this patch is merged to stable, clear_page should be fixed, too. Unfortunately, recent zram removes it by "same page merge" feature so it's hard to backport this patch to -stable tree. I will handle it when I receive the mail from stable tree maintainer to merge this patch to backport. Fixes: 42e99bd9 ("zram: optimize memory operations with clear_page()/copy_page()") Link: http://lkml.kernel.org/r/1492042622-12074-2-git-send-email-minchan@kernel.orgSigned-off-by:
Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@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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Paolo Bonzini authored
commit 06ce521a upstream. handle_vmon gets a reference on VMXON region page, but does not release it. Release the reference. Found by syzkaller; based on a patch by Dmitry. Reported-by:
Dmitry Vyukov <dvyukov@google.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.16: use skip_emulated_instruction()] Signed-off-by:
Ben Hutchings <ben@decadent.org.uk> Signed-off-by:
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Greg Kroah-Hartman authored
This reverts commit 6280ac93 which is commit 6c356eda upstream. It shouldn't have been included in a stable release. Reported-by:
Amit Pundir <amit.pundir@linaro.org> Cc: Felix Fietkau <nbd@nbd.name> Cc: John Crispin <john@phrozen.org> Cc: James Hogan <james.hogan@imgtec.com> Signed-off-by:
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Max Bires authored
commit f2cfa58b upstream. Without a bool string present, using "# CONFIG_DEVPORT is not set" in defconfig files would not actually unset devport. This esnured that /dev/port was always on, but there are reasons a user may wish to disable it (smaller kernel, attack surface reduction) if it's not being used. Adding a message here in order to make this user visible. Signed-off-by:
Max Bires <jbires@google.com> Acked-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
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Geert Uytterhoeven authored
commit 309124e2 upstream. According to full-history-linux commit d3794f4fa7c3edc3 ("[PATCH] M68k update (part 25)"), port operations are allowed on m68k if CONFIG_ISA is defined. However, commit 153dcc54 ("[PATCH] mem driver: fix conditional on isa i/o support") accidentally changed an "||" into an "&&", disabling it completely on m68k. This logic was retained when introducing the DEVPORT symbol in commit 4f911d64 ("Make /dev/port conditional on config symbol"). Drop the bogus dependency on !M68K to fix this. Fixes: 153dcc54 ("[PATCH] mem driver: fix conditional on isa i/o support") Signed-off-by:
Geert Uytterhoeven <geert@linux-m68k.org> Tested-by:
Al Stone <ahs3@redhat.com> Signed-off-by:
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Steven Rostedt (VMware) authored
commit 82cc4fc2 upstream. When two function probes are added to set_ftrace_filter, and then one of them is removed, the update to the function locations is not performed, and the record keeping of the function states are corrupted, and causes an ftrace_bug() to occur. This is easily reproducable by adding two probes, removing one, and then adding it back again. # cd /sys/kernel/debug/tracing # echo schedule:traceoff > set_ftrace_filter # echo do_IRQ:traceoff > set_ftrace_filter # echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter # echo do_IRQ:traceoff > set_ftrace_filter Causes: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1098 at kernel/trace/ftrace.c:2369 ftrace_get_addr_curr+0x143/0x220 Modules linked in: [...] CPU: 2 PID: 1098 Comm: bash Not tainted 4.10.0-test+ #405 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012 Call Trace: dump_stack+0x68/0x9f __warn+0x111/0x130 ? trace_irq_work_interrupt+0xa0/0xa0 warn_slowpath_null+0x1d/0x20 ftrace_get_addr_curr+0x143/0x220 ? __fentry__+0x10/0x10 ftrace_replace_code+0xe3/0x4f0 ? ftrace_int3_handler+0x90/0x90 ? printk+0x99/0xb5 ? 0xffffffff81000000 ftrace_modify_all_code+0x97/0x110 arch_ftrace_update_code+0x10/0x20 ftrace_run_update_code+0x1c/0x60 ftrace_run_modify_code.isra.48.constprop.62+0x8e/0xd0 register_ftrace_function_probe+0x4b6/0x590 ? ftrace_startup+0x310/0x310 ? debug_lockdep_rcu_enabled.part.4+0x1a/0x30 ? update_stack_state+0x88/0x110 ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320 ? preempt_count_sub+0x18/0xd0 ? mutex_lock_nested+0x104/0x800 ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320 ? __unwind_start+0x1c0/0x1c0 ? _mutex_lock_nest_lock+0x800/0x800 ftrace_trace_probe_callback.isra.3+0xc0/0x130 ? func_set_flag+0xe0/0xe0 ? __lock_acquire+0x642/0x1790 ? __might_fault+0x1e/0x20 ? trace_get_user+0x398/0x470 ? strcmp+0x35/0x60 ftrace_trace_onoff_callback+0x48/0x70 ftrace_regex_write.isra.43.part.44+0x251/0x320 ? match_records+0x420/0x420 ftrace_filter_write+0x2b/0x30 __vfs_write+0xd7/0x330 ? do_loop_readv_writev+0x120/0x120 ? locks_remove_posix+0x90/0x2f0 ? do_lock_file_wait+0x160/0x160 ? __lock_is_held+0x93/0x100 ? rcu_read_lock_sched_held+0x5c/0xb0 ? preempt_count_sub+0x18/0xd0 ? __sb_start_write+0x10a/0x230 ? vfs_write+0x222/0x240 vfs_write+0xef/0x240 SyS_write+0xab/0x130 ? SyS_read+0x130/0x130 ? trace_hardirqs_on_caller+0x182/0x280 ? trace_hardirqs_on_thunk+0x1a/0x1c entry_SYSCALL_64_fastpath+0x18/0xad RIP: 0033:0x7fe61c157c30 RSP: 002b:00007ffe87890258 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: ffffffff8114a410 RCX: 00007fe61c157c30 RDX: 0000000000000010 RSI: 000055814798f5e0 RDI: 0000000000000001 RBP: ffff8800c9027f98 R08: 00007fe61c422740 R09: 00007fe61ca53700 R10: 0000000000000073 R11: 0000000000000246 R12: 0000558147a36400 R13: 00007ffe8788f160 R14: 0000000000000024 R15: 00007ffe8788f15c ? trace_hardirqs_off_caller+0xc0/0x110 ---[ end trace 99fa09b3d9869c2c ]--- Bad trampoline accounting at: ffffffff81cc3b00 (do_IRQ+0x0/0x150) Fixes: 59df055f ("ftrace: trace different functions with a different tracer") Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by:
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Tyler Baker authored
commit 75eb5e1e upstream. The raw_spinlock in the IMX GPCV2 interupt chip is not initialized before usage. That results in a lockdep splat: INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. Add the missing raw_spin_lock_init() to the setup code. Fixes: e324c4dc ("irqchip/imx-gpcv2: IMX GPCv2 driver for wakeup sources") Signed-off-by:
Tyler Baker <tyler.baker@linaro.org> Reviewed-by:
Fabio Estevam <fabio.estevam@nxp.com> Cc: jason@lakedaemon.net Cc: marc.zyngier@arm.com Cc: shawnguo@kernel.org Cc: andrew.smirnov@gmail.com Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20170413222731.5917-1-tyler.baker@linaro.orgSigned-off-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Dan Williams authored
commit 0beb2012 upstream. Holding the reconfig_mutex over a potential userspace fault sets up a lockdep dependency chain between filesystem-DAX and the libnvdimm ioctl path. Move the user access outside of the lock. [ INFO: possible circular locking dependency detected ] 4.11.0-rc3+ #13 Tainted: G W O ------------------------------------------------------- fallocate/16656 is trying to acquire lock: (&nvdimm_bus->reconfig_mutex){+.+.+.}, at: [<ffffffffa00080b1>] nvdimm_bus_lock+0x21/0x30 [libnvdimm] but task is already holding lock: (jbd2_handle){++++..}, at: [<ffffffff813b4944>] start_this_handle+0x104/0x460 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (jbd2_handle){++++..}: lock_acquire+0xbd/0x200 start_this_handle+0x16a/0x460 jbd2__journal_start+0xe9/0x2d0 __ext4_journal_start_sb+0x89/0x1c0 ext4_dirty_inode+0x32/0x70 __mark_inode_dirty+0x235/0x670 generic_update_time+0x87/0xd0 touch_atime+0xa9/0xd0 ext4_file_mmap+0x90/0xb0 mmap_region+0x370/0x5b0 do_mmap+0x415/0x4f0 vm_mmap_pgoff+0xd7/0x120 SyS_mmap_pgoff+0x1c5/0x290 SyS_mmap+0x22/0x30 entry_SYSCALL_64_fastpath+0x1f/0xc2 -> #1 (&mm->mmap_sem){++++++}: lock_acquire+0xbd/0x200 __might_fault+0x70/0xa0 __nd_ioctl+0x683/0x720 [libnvdimm] nvdimm_ioctl+0x8b/0xe0 [libnvdimm] do_vfs_ioctl+0xa8/0x740 SyS_ioctl+0x79/0x90 do_syscall_64+0x6c/0x200 return_from_SYSCALL_64+0x0/0x7a -> #0 (&nvdimm_bus->reconfig_mutex){+.+.+.}: __lock_acquire+0x16b6/0x1730 lock_acquire+0xbd/0x200 __mutex_lock+0x88/0x9b0 mutex_lock_nested+0x1b/0x20 nvdimm_bus_lock+0x21/0x30 [libnvdimm] nvdimm_forget_poison+0x25/0x50 [libnvdimm] nvdimm_clear_poison+0x106/0x140 [libnvdimm] pmem_do_bvec+0x1c2/0x2b0 [nd_pmem] pmem_make_request+0xf9/0x270 [nd_pmem] generic_make_request+0x118/0x3b0 submit_bio+0x75/0x150 Fixes: 62232e45 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices") Cc: Dave Jiang <dave.jiang@intel.com> Reported-by:
Vishal Verma <vishal.l.verma@intel.com> Signed-off-by:
Dan Williams <dan.j.williams@intel.com> Signed-off-by:
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Juergen Gross authored
commit 9121b15b upstream. Connecting to the backend isn't working reliably in xen-fbfront: in case XenbusStateInitWait of the backend has been missed the backend transition to XenbusStateConnected will trigger the connected state only without doing the actions required when the backend has connected. Signed-off-by:
Juergen Gross <jgross@suse.com> Reviewed-by:
Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by:
Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by:
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Martin K. Petersen authored
commit 7c856152 upstream. We previously made sure that the reported disk capacity was less than 0xffffffff blocks when the kernel was not compiled with large sector_t support (CONFIG_LBDAF). However, this check assumed that the capacity was reported in units of 512 bytes. Add a sanity check function to ensure that we only enable disks if the entire reported capacity can be expressed in terms of sector_t. Reported-by:
Steve Magnani <steve.magnani@digidescorp.com> Cc: Bart Van Assche <Bart.VanAssche@sandisk.com> Reviewed-by:
Bart Van Assche <Bart.VanAssche@sandisk.com> Signed-off-by:
Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by:
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Fam Zheng authored
commit 67804145 upstream. If device reports a small max_xfer_blocks and a zero opt_xfer_blocks, we end up using BLK_DEF_MAX_SECTORS, which is wrong and r/w of that size may get error. [mkp: tweaked to avoid setting rw_max twice and added typecast] Fixes: ca369d51 ("block/sd: Fix device-imposed transfer length limits") Signed-off-by:
Fam Zheng <famz@redhat.com> Signed-off-by:
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Martin K. Petersen authored
commit a00a7862 upstream. Kefeng Wang discovered that old versions of the QEMU CD driver would return mangled mode data causing us to walk off the end of the buffer in an attempt to parse it. Sanity check the returned mode sense data. Reported-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Tested-by:
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Nicholas Bellinger authored
commit 1c99de98 upstream. Once upon a time back in 2009, a work-around was added to support the GlobalSAN iSCSI initiator v3.3 for MacOSX, which during login did not propose nor respond to MaxBurstLength, FirstBurstLength, DefaultTime2Wait and DefaultTime2Retain keys. The work-around in iscsi_check_proposer_for_optional_reply() allowed the missing keys to be proposed, but did not require waiting for a response before moving to full feature phase operation. This allowed GlobalSAN v3.3 to work out-of-the box, and for many years we didn't run into login interopt issues with any other initiators.. Until recently, when Martin tried a QLogic 57840S iSCSI Offload HBA on Windows 2016 which completed login, but subsequently failed with: Got unknown iSCSI OpCode: 0x43 The issue was QLogic MSFT side did not propose DefaultTime2Wait + DefaultTime2Retain, so LIO proposes them itself, and immediately transitions to full feature phase because of the GlobalSAN hack. However, the QLogic MSFT side still attempts to respond to DefaultTime2Retain + DefaultTime2Wait, even though LIO has set ISCSI_FLAG_LOGIN_NEXT_STAGE3 + ISCSI_FLAG_LOGIN_TRANSIT in last login response. So while the QLogic MSFT side should have been proposing these two keys to start, it was doing the correct thing per RFC-3720 attempting to respond to proposed keys before transitioning to full feature phase. All that said, recent versions of GlobalSAN iSCSI (v5.3.0.541) does correctly propose the four keys during login, making the original work-around moot. So in order to allow QLogic MSFT to run unmodified as-is, go ahead and drop this long standing work-around. Reported-by:
Martin Svec <martin.svec@zoner.cz> Cc: Martin Svec <martin.svec@zoner.cz> Cc: Himanshu Madhani <Himanshu.Madhani@cavium.com> Cc: Arun Easi <arun.easi@cavium.com> Signed-off-by:
Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by:
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Nicholas Bellinger authored
commit efb2ea77 upstream. This patch fixes a iscsi-target specific TMR reference leak during session shutdown, that could occur when a TMR was quiesced before the hand-off back to iscsi-target code via transport_cmd_check_stop_to_fabric(). The reference leak happens because iscsit_free_cmd() was incorrectly skipping the final target_put_sess_cmd() for TMRs when transport_generic_free_cmd() returned zero because the se_cmd->cmd_kref did not reach zero, due to the missing se_cmd assignment in original code. The result was iscsi_cmd and it's associated se_cmd memory would be freed once se_sess->sess_cmd_map where released, but the associated se_tmr_req was leaked and remained part of se_device->dev_tmr_list. This bug would manfiest itself as kernel paging request OOPsen in core_tmr_lun_reset(), when a left-over se_tmr_req attempted to dereference it's se_cmd pointer that had already been released during normal session shutdown. To address this bug, go ahead and treat ISCSI_OP_SCSI_CMD and ISCSI_OP_SCSI_TMFUNC the same when there is an extra se_cmd->cmd_kref to drop in iscsit_free_cmd(), and use op_scsi to signal __iscsit_free_cmd() when the former needs to clear any further iscsi related I/O state. Reported-by:
Rob Millner <rlm@daterainc.com> Cc: Rob Millner <rlm@daterainc.com> Reported-by:
Chu Yuan Lin <cyl@datera.io> Cc: Chu Yuan Lin <cyl@datera.io> Tested-by:
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Dan Williams authored
commit b03b99a3 upstream. While reviewing the -stable patch for commit 86ef58a4 "nfit, libnvdimm: fix interleave set cookie calculation" Ben noted: "This is returning an int, thus it's effectively doing a 32-bit comparison and not the 64-bit comparison you say is needed." Update the compare operation to be immune to this integer demotion problem. Cc: Nicholas Moulin <nicholas.w.moulin@linux.intel.com> Fixes: 86ef58a4 ("nfit, libnvdimm: fix interleave set cookie calculation") Reported-by:
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Thomas Gleixner authored
commit 6fdc6dd9 upstream. The vsyscall32 sysctl can racy against a concurrent fork when it switches from disabled to enabled: arch_setup_additional_pages() if (vdso32_enabled) --> No mapping sysctl.vsysscall32() --> vdso32_enabled = true create_elf_tables() ARCH_DLINFO_IA32 if (vdso32_enabled) { --> Add VDSO entry with NULL pointer Make ARCH_DLINFO_IA32 check whether the VDSO mapping has been set up for the newly forked process or not. Signed-off-by:
Andy Lutomirski <luto@amacapital.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathias Krause <minipli@googlemail.com> Link: http://lkml.kernel.org/r/20170410151723.602367196@linutronix.deSigned-off-by:
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Mathias Krause authored
commit c06989da upstream. vdso_enabled can be set to arbitrary integer values via the kernel command line 'vdso32=' parameter or via 'sysctl abi.vsyscall32'. load_vdso32() only maps VDSO if vdso_enabled == 1, but ARCH_DLINFO_IA32 merily checks for vdso_enabled != 0. As a consequence the AT_SYSINFO_EHDR auxiliary vector for the VDSO_ENTRY is emitted with a NULL pointer which causes a segfault when the application tries to use the VDSO. Restrict the valid arguments on the command line and the sysctl to 0 and 1. Fixes: b0b49f26 ("x86, vdso: Remove compat vdso support") Signed-off-by:
Mathias Krause <minipli@googlemail.com> Acked-by:
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Peter Zijlstra authored
commit f2200ac3 upstream. When the perf_branch_entry::{in_tx,abort,cycles} fields were added, intel_pmu_lbr_read_32() wasn't updated to initialize them. Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Fixes: 135c5612 ("perf/x86/intel: Support Haswell/v4 LBR format") Signed-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Cameron Gutman authored
commit 53763668 upstream. Signed-off-by:
Cameron Gutman <aicommander@gmail.com> Signed-off-by:
Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by:
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Germano Percossi authored
commit 1fa839b4 upstream. This fixes Continuous Availability when errors during file reopen are encountered. cifs_user_readv and cifs_user_writev would wait for ever if results of cifs_reopen_file are not stored and for later inspection. In fact, results are checked and, in case of errors, a chain of function calls leading to reads and writes to be scheduled in a separate thread is skipped. These threads will wake up the corresponding waiters once reads and writes are done. However, given the return value is not stored, when rc is checked for errors a previous one (always zero) is inspected instead. This leads to pending reads/writes added to the list, making cifs_user_readv and cifs_user_writev wait for ever. Signed-off-by:
Germano Percossi <germano.percossi@citrix.com> Reviewed-by:
Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by:
Steve French <smfrench@gmail.com> Signed-off-by:
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Ilia Mirkin authored
commit f94773b9 upstream. The NV4A (aka NV44A) is an oddity in the family. It only comes in AGP and PCI varieties, rather than a core PCIE chip with a bridge for AGP/PCI as necessary. As a result, it appears that the MMU is also non-functional. For AGP cards, the vast majority of the NV4A lineup, this worked out since we force AGP cards to use the nv04 mmu. However for PCI variants, this did not work. Switching to the NV04 MMU makes it work like a charm. Thanks to mwk for the suggestion. This should be a no-op for NV4A AGP boards, as they were using it already. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70388Signed-off-by:
Ilia Mirkin <imirkin@alum.mit.edu> Signed-off-by:
Ben Skeggs <bskeggs@redhat.com> Signed-off-by:
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Ilia Mirkin authored
commit 83bce9c2 upstream. Signed-off-by:
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Kirill A. Shutemov authored
commit 5b7abeae upstream. Yet another instance of the same race. Fix is identical to change_huge_pmd(). See "thp: fix MADV_DONTNEED vs. numa balancing race" for more details. Link: http://lkml.kernel.org/r/20170302151034.27829-5-kirill.shutemov@linux.intel.comSigned-off-by:
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Signed-off-by:
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Tejun Heo authored
commit 77f88796 upstream. Creation of a kthread goes through a couple interlocked stages between the kthread itself and its creator. Once the new kthread starts running, it initializes itself and wakes up the creator. The creator then can further configure the kthread and then let it start doing its job by waking it up. In this configuration-by-creator stage, the creator is the only one that can wake it up but the kthread is visible to userland. When altering the kthread's attributes from userland is allowed, this is fine; however, for cases where CPU affinity is critical, kthread_bind() is used to first disable affinity changes from userland and then set the affinity. This also prevents the kthread from being migrated into non-root cgroups as that can affect the CPU affinity and many other things. Unfortunately, the cgroup side of protection is racy. While the PF_NO_SETAFFINITY flag prevents further migrations, userland can win the race before the creator sets the flag with kthread_bind() and put the kthread in a non-root cgroup, which can lead to all sorts of problems including incorrect CPU affinity and starvation. This bug got triggered by userland which periodically tries to migrate all processes in the root cpuset cgroup to a non-root one. Per-cpu workqueue workers got caught while being created and ended up with incorrected CPU affinity breaking concurrency management and sometimes stalling workqueue execution. This patch adds task->no_cgroup_migration which disallows the task to be migrated by userland. kthreadd starts with the flag set making every child kthread start in the root cgroup with migration disallowed. The flag is cleared after the kthread finishes initialization by which time PF_NO_SETAFFINITY is set if the kthread should stay in the root cgroup. It'd be better to wait for the initialization instead of failing but I couldn't think of a way of implementing that without adding either a new PF flag, or sleeping and retrying from waiting side. Even if userland depends on changing cgroup membership of a kthread, it either has to be synchronized with kthread_create() or periodically repeat, so it's unlikely that this would break anything. v2: Switch to a simpler implementation using a new task_struct bit field suggested by Oleg. Signed-off-by:
Tejun Heo <tj@kernel.org> Suggested-by:
Oleg Nesterov <oleg@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Reported-and-debugged-by:
Chris Mason <clm@fb.com> Signed-off-by:
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- 18 Apr, 2017 15 commits
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Greg Kroah-Hartman authored
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Thomas Falcon authored
commit 7b596738 upstream. This patch is based on an earlier one submitted by Jon Maxwell with the following commit message: "We recently encountered a bug where a few customers using ibmveth on the same LPAR hit an issue where a TCP session hung when large receive was enabled. Closer analysis revealed that the session was stuck because the one side was advertising a zero window repeatedly. We narrowed this down to the fact the ibmveth driver did not set gso_size which is translated by TCP into the MSS later up the stack. The MSS is used to calculate the TCP window size and as that was abnormally large, it was calculating a zero window, even although the sockets receive buffer was completely empty." We rely on the Virtual I/O Server partition in a pseries environment to provide the MSS through the TCP header checksum field. The stipulation is that users should not disable checksum offloading if rx packet aggregation is enabled through VIOS. Some firmware offerings provide the MSS in the RX buffer. This is signalled by a bit in the RX queue descriptor. Reviewed-by:
Brian King <brking@linux.vnet.ibm.com> Reviewed-by:
Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com> Reviewed-by:
Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reviewed-by:
Jonathan Maxwell <jmaxwell37@gmail.com> Reviewed-by:
David Dai <zdai@us.ibm.com> Signed-off-by:
Thomas Falcon <tlfalcon@linux.vnet.ibm.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by:
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Jack Morgenstein authored
commit 7c3945bc upstream. Save the qp context flags byte containing the flag disabling vlan stripping in the RESET to INIT qp transition, rather than in the INIT to RTR transition. Per the firmware spec, the flags in this byte are active in the RESET to INIT transition. As a result of saving the flags in the incorrect qp transition, when switching dynamically from VGT to VST and back to VGT, the vlan remained stripped (as is required for VST) and did not return to not-stripped (as is required for VGT). Fixes: f0f829bf ("net/mlx4_core: Add immediate activate for VGT->VST->VGT") Signed-off-by:
Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by:
Tariq Toukan <tariqt@mellanox.com> Signed-off-by:
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Jack Morgenstein authored
commit 291c566a upstream. In function mlx4_cq_completion() and mlx4_cq_event(), the radix_tree_lookup requires a rcu_read_lock. This is mandatory: if another core frees the CQ, it could run the radix_tree_node_rcu_free() call_rcu() callback while its being used by the radix tree lookup function. Additionally, in function mlx4_cq_event(), since we are adding the rcu lock around the radix-tree lookup, we no longer need to take the spinlock. Also, the synchronize_irq() call for the async event eliminates the need for incrementing the cq reference count in mlx4_cq_event(). Other changes: 1. In function mlx4_cq_free(), replace spin_lock_irq with spin_lock: we no longer take this spinlock in the interrupt context. The spinlock here, therefore, simply protects against different threads simultaneously invoking mlx4_cq_free() for different cq's. 2. In function mlx4_cq_free(), we move the radix tree delete to before the synchronize_irq() calls. This guarantees that we will not access this cq during any subsequent interrupts, and therefore can safely free the CQ after the synchronize_irq calls. The rcu_read_lock in the interrupt handlers only needs to protect against corrupting the radix tree; the interrupt handlers may access the cq outside the rcu_read_lock due to the synchronize_irq calls which protect against premature freeing of the cq. 3. In function mlx4_cq_event(), we change the mlx_warn message to mlx4_dbg. 4. We leave the cq reference count mechanism in place, because it is still needed for the cq completion tasklet mechanism. Fixes: 6d90aa5c ("net/mlx4_core: Make sure there are no pending async events when freeing CQ") Fixes: 225c7b1f ("IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters") Signed-off-by:
Matan Barak <matanb@mellanox.com> Signed-off-by:
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Eugenia Emantayev authored
commit 6496bbf0 upstream. Single send WQE in RX buffer should be stamped with software ownership in order to prevent the flow of QP in error in FW once UPDATE_QP is called. Fixes: 9f519f68 ('mlx4_en: Not using Shared Receive Queues') Signed-off-by:
Eugenia Emantayev <eugenia@mellanox.com> Signed-off-by:
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Guenter Roeck authored
commit 22547c4c upstream. On a system with a defective USB device connected to an USB hub, an endless sequence of port connect events was observed. The sequence of events as observed is as follows: - Port reports connected event (port status=USB_PORT_STAT_CONNECTION). - Event handler debounces port and resets it by calling hub_port_reset(). - hub_port_reset() calls hub_port_wait_reset() to wait for the reset to complete. - The reset completes, but USB_PORT_STAT_CONNECTION is not immediately set in the port status register. - hub_port_wait_reset() returns -ENOTCONN. - Port initialization sequence is aborted. - A few milliseconds later, the port again reports a connected event, and the sequence repeats. This continues either forever or, randomly, stops if the connection is already re-established when the port status is read. It results in a high rate of udev events. This in turn destabilizes userspace since the above sequence holds the device mutex pretty much continuously and prevents userspace from actually reading the device status. To prevent the problem from happening, let's wait for the connection to be re-established after a port reset. If the device was actually disconnected, the code will still return an error, but it will do so only after the long reset timeout. Cc: Douglas Anderson <dianders@chromium.org> Signed-off-by:
Guenter Roeck <linux@roeck-us.net> Acked-by:
Alan Stern <stern@rowland.harvard.edu> Signed-off-by:
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Gabriel Krisman Bertazi authored
commit 36e1f3d1 upstream. While stressing memory and IO at the same time we changed SMT settings, we were able to consistently trigger deadlocks in the mm system, which froze the entire machine. I think that under memory stress conditions, the large allocations performed by blk_mq_init_rq_map may trigger a reclaim, which stalls waiting on the block layer remmaping completion, thus deadlocking the system. The trace below was collected after the machine stalled, waiting for the hotplug event completion. The simplest fix for this is to make allocations in this path non-reclaimable, with GFP_NOIO. With this patch, We couldn't hit the issue anymore. This should apply on top of Jens's for-next branch cleanly. Changes since v1: - Use GFP_NOIO instead of GFP_NOWAIT. Call Trace: [c000000f0160aaf0] [c000000f0160ab50] 0xc000000f0160ab50 (unreliable) [c000000f0160acc0] [c000000000016624] __switch_to+0x2e4/0x430 [c000000f0160ad20] [c000000000b1a880] __schedule+0x310/0x9b0 [c000000f0160ae00] [c000000000b1af68] schedule+0x48/0xc0 [c000000f0160ae30] [c000000000b1b4b0] schedule_preempt_disabled+0x20/0x30 [c000000f0160ae50] [c000000000b1d4fc] __mutex_lock_slowpath+0xec/0x1f0 [c000000f0160aed0] [c000000000b1d678] mutex_lock+0x78/0xa0 [c000000f0160af00] [d000000019413cac] xfs_reclaim_inodes_ag+0x33c/0x380 [xfs] [c000000f0160b0b0] [d000000019415164] xfs_reclaim_inodes_nr+0x54/0x70 [xfs] [c000000f0160b0f0] [d0000000194297f8] xfs_fs_free_cached_objects+0x38/0x60 [xfs] [c000000f0160b120] [c0000000003172c8] super_cache_scan+0x1f8/0x210 [c000000f0160b190] [c00000000026301c] shrink_slab.part.13+0x21c/0x4c0 [c000000f0160b2d0] [c000000000268088] shrink_zone+0x2d8/0x3c0 [c000000f0160b380] [c00000000026834c] do_try_to_free_pages+0x1dc/0x520 [c000000f0160b450] [c00000000026876c] try_to_free_pages+0xdc/0x250 [c000000f0160b4e0] [c000000000251978] __alloc_pages_nodemask+0x868/0x10d0 [c000000f0160b6f0] [c000000000567030] blk_mq_init_rq_map+0x160/0x380 [c000000f0160b7a0] [c00000000056758c] blk_mq_map_swqueue+0x33c/0x360 [c000000f0160b820] [c000000000567904] blk_mq_queue_reinit+0x64/0xb0 [c000000f0160b850] [c00000000056a16c] blk_mq_queue_reinit_notify+0x19c/0x250 [c000000f0160b8a0] [c0000000000f5d38] notifier_call_chain+0x98/0x100 [c000000f0160b8f0] [c0000000000c5fb0] __cpu_notify+0x70/0xe0 [c000000f0160b930] [c0000000000c63c4] notify_prepare+0x44/0xb0 [c000000f0160b9b0] [c0000000000c52f4] cpuhp_invoke_callback+0x84/0x250 [c000000f0160ba10] [c0000000000c570c] cpuhp_up_callbacks+0x5c/0x120 [c000000f0160ba60] [c0000000000c7cb8] _cpu_up+0xf8/0x1d0 [c000000f0160bac0] [c0000000000c7eb0] do_cpu_up+0x120/0x150 [c000000f0160bb40] [c0000000006fe024] cpu_subsys_online+0x64/0xe0 [c000000f0160bb90] [c0000000006f5124] device_online+0xb4/0x120 [c000000f0160bbd0] [c0000000006f5244] online_store+0xb4/0xc0 [c000000f0160bc20] [c0000000006f0a68] dev_attr_store+0x68/0xa0 [c000000f0160bc60] [c0000000003ccc30] sysfs_kf_write+0x80/0xb0 [c000000f0160bca0] [c0000000003cbabc] kernfs_fop_write+0x17c/0x250 [c000000f0160bcf0] [c00000000030fe6c] __vfs_write+0x6c/0x1e0 [c000000f0160bd90] [c000000000311490] vfs_write+0xd0/0x270 [c000000f0160bde0] [c0000000003131fc] SyS_write+0x6c/0x110 [c000000f0160be30] [c000000000009204] system_call+0x38/0xec Signed-off-by:
Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Cc: Brian King <brking@linux.vnet.ibm.com> Cc: Douglas Miller <dougmill@linux.vnet.ibm.com> Cc: linux-block@vger.kernel.org Cc: linux-scsi@vger.kernel.org Signed-off-by:
Jens Axboe <axboe@fb.com> Signed-off-by:
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Andrey Konovalov authored
commit 2b6867c2 upstream. Subtracting tp_sizeof_priv from tp_block_size and casting to int to check whether one is less then the other doesn't always work (both of them are unsigned ints). Compare them as is instead. Also cast tp_sizeof_priv to u64 before using BLK_PLUS_PRIV, as it can overflow inside BLK_PLUS_PRIV otherwise. Signed-off-by:
Andrey Konovalov <andreyknvl@google.com> Acked-by:
Eric Dumazet <edumazet@google.com> Signed-off-by:
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Horia Geantă authored
commit 40c98cb5 upstream. RNG instantiation was previously fixed by commit 62743a41 ("crypto: caam - fix RNG init descriptor ret. code checking") while deinstantiation was not addressed. Since the descriptors used are similar, in the sense that they both end with a JUMP HALT command, checking for errors should be similar too, i.e. status code 7000_0000h should be considered successful. Fixes: 1005bccd ("crypto: caam - enable instantiation of all RNG4 state handles") Signed-off-by:
Horia Geantă <horia.geanta@nxp.com> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
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Matt Redfearn authored
commit c25f8064 upstream. Commit dda45f70 ("MIPS: Switch to the irq_stack in interrupts") changed both the normal and vectored interrupt handlers. Unfortunately the vectored version, "except_vec_vi_handler", was incorrectly modified to unconditionally jal to plat_irq_dispatch, rather than doing a jalr to the vectored handler that has been set up. This is ok for many platforms which set the vectored handler to plat_irq_dispatch anyway, but will cause problems with platforms that use other handlers. Fixes: dda45f70 ("MIPS: Switch to the irq_stack in interrupts") Signed-off-by:
Matt Redfearn <matt.redfearn@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/15110/Signed-off-by:
James Hogan <james.hogan@imgtec.com> Signed-off-by:
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Matt Redfearn authored
commit 3cc3434f upstream. Since do_IRQ is now invoked on a separate IRQ stack, we select HAVE_IRQ_EXIT_ON_IRQ_STACK so that softirq's may be invoked directly from irq_exit(), rather than requiring do_softirq_own_stack. Signed-off-by:
Jason A. Donenfeld <jason@zx2c4.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/14744/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> Signed-off-by:
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Matt Redfearn authored
commit dda45f70 upstream. When enterring interrupt context via handle_int or except_vec_vi, switch to the irq_stack of the current CPU if it is not already in use. The current stack pointer is masked with the thread size and compared to the base or the irq stack. If it does not match then the stack pointer is set to the top of that stack, otherwise this is a nested irq being handled on the irq stack so the stack pointer should be left as it was. The in-use stack pointer is placed in the callee saved register s1. It will be saved to the stack when plat_irq_dispatch is invoked and can be restored once control returns here. Signed-off-by:
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Matt Redfearn authored
commit 510d8636 upstream. The SAVE_SOME macro is used to save the execution context on all exceptions. If an exception occurs while executing user code, the stack is switched to the kernel's stack for the current task, and register $28 is switched to point to the current_thread_info, which is at the bottom of the stack region. If the exception occurs while executing kernel code, the stack is left, and this change ensures that register $28 is not updated. This is the correct behaviour when the kernel can be executing on the separate irq stack, because the thread_info will not be at the base of it. With this change, register $28 is only switched to it's kernel conventional usage of the currrent thread info pointer at the point at which execution enters kernel space. Doing it on every exception was redundant, but OK without an IRQ stack, but will be erroneous once that is introduced. Signed-off-by:
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Matt Redfearn authored
commit d42d8d10 upstream. Within unwind stack, check if the stack pointer being unwound is within the CPU's irq_stack and if so use that page rather than the task's stack page. Signed-off-by:
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Matt Redfearn authored
commit fe8bd18f upstream. Allocate a per-cpu irq stack for use within interrupt handlers. Also add a utility function on_irq_stack to determine if a given stack pointer is within the irq stack for that cpu. Signed-off-by:
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