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2019-06-17jump_label: Add a jump_label_can_update() helperDaniel Bristot de Oliveira1-11/+18
Move the check if a jump_entry is valid to a function. No functional change. Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris von Recklinghausen <crecklin@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Scott Wood <swood@redhat.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/56b69bd3f8e644ed64f2dbde7c088030b8cbe76b.1560325897.git.bristot@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17Merge tag 'v5.2-rc5' into locking/core, to pick up fixesIngo Molnar47-264/+256
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-16Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "A set of small fixes: - Repair the ktime_get_coarse() functions so they actually deliver what they are supposed to: tick granular time stamps. The current code missed to add the accumulated nanoseconds part of the timekeeper so the resulting granularity was 1 second. - Prevent the tracer from infinitely recursing into time getter functions in the arm architectured timer by marking these functions notrace - Fix a trivial compiler warning caused by wrong qualifier ordering" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Repair ktime_get_coarse*() granularity clocksource/drivers/arm_arch_timer: Don't trace count reader functions clocksource/drivers/timer-ti-dm: Change to new style declaration
2019-06-15Merge tag 'trace-v5.2-rc4' of ↵Linus Torvalds5-14/+35
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Out of range read of stack trace output - Fix for NULL pointer dereference in trace_uprobe_create() - Fix to a livepatching / ftrace permission race in the module code - Fix for NULL pointer dereference in free_ftrace_func_mapper() - A couple of build warning clean ups * tag 'trace-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Fix NULL pointer dereference in free_ftrace_func_mapper() module: Fix livepatch/ftrace module text permissions race tracing/uprobe: Fix obsolete comment on trace_uprobe_create() tracing/uprobe: Fix NULL pointer dereference in trace_uprobe_create() tracing: Make two symbols static tracing: avoid build warning with HAVE_NOP_MCOUNT tracing: Fix out-of-range read in trace_stack_print()
2019-06-14Merge branch 'for-5.2-fixes' of ↵Linus Torvalds3-32/+91
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: "This has an unusually high density of tricky fixes: - task_get_css() could deadlock when it races against a dying cgroup. - cgroup.procs didn't list thread group leaders with live threads. This could mislead readers to think that a cgroup is empty when it's not. Fixed by making PROCS iterator include dead tasks. I made a couple mistakes making this change and this pull request contains a couple follow-up patches. - When cpusets run out of online cpus, it updates cpusmasks of member tasks in bizarre ways. Joel improved the behavior significantly" * 'for-5.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cpuset: restore sanity to cpuset_cpus_allowed_fallback() cgroup: Fix css_task_iter_advance_css_set() cset skip condition cgroup: css_task_iter_skip()'d iterators must be advanced before accessed cgroup: Include dying leaders with live threads in PROCS iterations cgroup: Implement css_task_iter_skip() cgroup: Call cgroup_release() before __exit_signal() docs cgroups: add another example size for hugetlb cgroup: Use css_tryget() instead of css_tryget_online() in task_get_css()
2019-06-14ftrace: Fix NULL pointer dereference in free_ftrace_func_mapper()Wei Li1-2/+5
The mapper may be NULL when called from register_ftrace_function_probe() with probe->data == NULL. This issue can be reproduced as follow (it may be covered by compiler optimization sometime): / # cat /sys/kernel/debug/tracing/set_ftrace_filter #### all functions enabled #### / # echo foo_bar:dump > /sys/kernel/debug/tracing/set_ftrace_filter [ 206.949100] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 206.952402] Mem abort info: [ 206.952819] ESR = 0x96000006 [ 206.955326] Exception class = DABT (current EL), IL = 32 bits [ 206.955844] SET = 0, FnV = 0 [ 206.956272] EA = 0, S1PTW = 0 [ 206.956652] Data abort info: [ 206.957320] ISV = 0, ISS = 0x00000006 [ 206.959271] CM = 0, WnR = 0 [ 206.959938] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000419f3a000 [ 206.960483] [0000000000000000] pgd=0000000411a87003, pud=0000000411a83003, pmd=0000000000000000 [ 206.964953] Internal error: Oops: 96000006 [#1] SMP [ 206.971122] Dumping ftrace buffer: [ 206.973677] (ftrace buffer empty) [ 206.975258] Modules linked in: [ 206.976631] Process sh (pid: 281, stack limit = 0x(____ptrval____)) [ 206.978449] CPU: 10 PID: 281 Comm: sh Not tainted 5.2.0-rc1+ #17 [ 206.978955] Hardware name: linux,dummy-virt (DT) [ 206.979883] pstate: 60000005 (nZCv daif -PAN -UAO) [ 206.980499] pc : free_ftrace_func_mapper+0x2c/0x118 [ 206.980874] lr : ftrace_count_free+0x68/0x80 [ 206.982539] sp : ffff0000182f3ab0 [ 206.983102] x29: ffff0000182f3ab0 x28: ffff8003d0ec1700 [ 206.983632] x27: ffff000013054b40 x26: 0000000000000001 [ 206.984000] x25: ffff00001385f000 x24: 0000000000000000 [ 206.984394] x23: ffff000013453000 x22: ffff000013054000 [ 206.984775] x21: 0000000000000000 x20: ffff00001385fe28 [ 206.986575] x19: ffff000013872c30 x18: 0000000000000000 [ 206.987111] x17: 0000000000000000 x16: 0000000000000000 [ 206.987491] x15: ffffffffffffffb0 x14: 0000000000000000 [ 206.987850] x13: 000000000017430e x12: 0000000000000580 [ 206.988251] x11: 0000000000000000 x10: cccccccccccccccc [ 206.988740] x9 : 0000000000000000 x8 : ffff000013917550 [ 206.990198] x7 : ffff000012fac2e8 x6 : ffff000012fac000 [ 206.991008] x5 : ffff0000103da588 x4 : 0000000000000001 [ 206.991395] x3 : 0000000000000001 x2 : ffff000013872a28 [ 206.991771] x1 : 0000000000000000 x0 : 0000000000000000 [ 206.992557] Call trace: [ 206.993101] free_ftrace_func_mapper+0x2c/0x118 [ 206.994827] ftrace_count_free+0x68/0x80 [ 206.995238] release_probe+0xfc/0x1d0 [ 206.995555] register_ftrace_function_probe+0x4a8/0x868 [ 206.995923] ftrace_trace_probe_callback.isra.4+0xb8/0x180 [ 206.996330] ftrace_dump_callback+0x50/0x70 [ 206.996663] ftrace_regex_write.isra.29+0x290/0x3a8 [ 206.997157] ftrace_filter_write+0x44/0x60 [ 206.998971] __vfs_write+0x64/0xf0 [ 206.999285] vfs_write+0x14c/0x2f0 [ 206.999591] ksys_write+0xbc/0x1b0 [ 206.999888] __arm64_sys_write+0x3c/0x58 [ 207.000246] el0_svc_common.constprop.0+0x408/0x5f0 [ 207.000607] el0_svc_handler+0x144/0x1c8 [ 207.000916] el0_svc+0x8/0xc [ 207.003699] Code: aa0003f8 a9025bf5 aa0103f5 f946ea80 (f9400303) [ 207.008388] ---[ end trace 7b6d11b5f542bdf1 ]--- [ 207.010126] Kernel panic - not syncing: Fatal exception [ 207.011322] SMP: stopping secondary CPUs [ 207.013956] Dumping ftrace buffer: [ 207.014595] (ftrace buffer empty) [ 207.015632] Kernel Offset: disabled [ 207.017187] CPU features: 0x002,20006008 [ 207.017985] Memory Limit: none [ 207.019825] ---[ end Kernel panic - not syncing: Fatal exception ]--- Link: http://lkml.kernel.org/r/20190606031754.10798-1-liwei391@huawei.com Signed-off-by: Wei Li <liwei391@huawei.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14module: Fix livepatch/ftrace module text permissions raceJosh Poimboeuf2-1/+15
It's possible for livepatch and ftrace to be toggling a module's text permissions at the same time, resulting in the following panic: BUG: unable to handle page fault for address: ffffffffc005b1d9 #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation PGD 3ea0c067 P4D 3ea0c067 PUD 3ea0e067 PMD 3cc13067 PTE 3b8a1061 Oops: 0003 [#1] PREEMPT SMP PTI CPU: 1 PID: 453 Comm: insmod Tainted: G O K 5.2.0-rc1-a188339ca5 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014 RIP: 0010:apply_relocate_add+0xbe/0x14c Code: fa 0b 74 21 48 83 fa 18 74 38 48 83 fa 0a 75 40 eb 08 48 83 38 00 74 33 eb 53 83 38 00 75 4e 89 08 89 c8 eb 0a 83 38 00 75 43 <89> 08 48 63 c1 48 39 c8 74 2e eb 48 83 38 00 75 32 48 29 c1 89 08 RSP: 0018:ffffb223c00dbb10 EFLAGS: 00010246 RAX: ffffffffc005b1d9 RBX: 0000000000000000 RCX: ffffffff8b200060 RDX: 000000000000000b RSI: 0000004b0000000b RDI: ffff96bdfcd33000 RBP: ffffb223c00dbb38 R08: ffffffffc005d040 R09: ffffffffc005c1f0 R10: ffff96bdfcd33c40 R11: ffff96bdfcd33b80 R12: 0000000000000018 R13: ffffffffc005c1f0 R14: ffffffffc005e708 R15: ffffffff8b2fbc74 FS: 00007f5f447beba8(0000) GS:ffff96bdff900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffc005b1d9 CR3: 000000003cedc002 CR4: 0000000000360ea0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: klp_init_object_loaded+0x10f/0x219 ? preempt_latency_start+0x21/0x57 klp_enable_patch+0x662/0x809 ? virt_to_head_page+0x3a/0x3c ? kfree+0x8c/0x126 patch_init+0x2ed/0x1000 [livepatch_test02] ? 0xffffffffc0060000 do_one_initcall+0x9f/0x1c5 ? kmem_cache_alloc_trace+0xc4/0xd4 ? do_init_module+0x27/0x210 do_init_module+0x5f/0x210 load_module+0x1c41/0x2290 ? fsnotify_path+0x3b/0x42 ? strstarts+0x2b/0x2b ? kernel_read+0x58/0x65 __do_sys_finit_module+0x9f/0xc3 ? __do_sys_finit_module+0x9f/0xc3 __x64_sys_finit_module+0x1a/0x1c do_syscall_64+0x52/0x61 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The above panic occurs when loading two modules at the same time with ftrace enabled, where at least one of the modules is a livepatch module: CPU0 CPU1 klp_enable_patch() klp_init_object_loaded() module_disable_ro() ftrace_module_enable() ftrace_arch_code_modify_post_process() set_all_modules_text_ro() klp_write_object_relocations() apply_relocate_add() *patches read-only code* - BOOM A similar race exists when toggling ftrace while loading a livepatch module. Fix it by ensuring that the livepatch and ftrace code patching operations -- and their respective permissions changes -- are protected by the text_mutex. Link: http://lkml.kernel.org/r/ab43d56ab909469ac5d2520c5d944ad6d4abd476.1560474114.git.jpoimboe@redhat.com Reported-by: Johannes Erdfelt <johannes@erdfelt.com> Fixes: 444d13ff10fb ("modules: add ro_after_init support") Acked-by: Jessica Yu <jeyu@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14tracing/uprobe: Fix obsolete comment on trace_uprobe_create()Eiichi Tsukata1-2/+0
Commit 0597c49c69d5 ("tracing/uprobes: Use dyn_event framework for uprobe events") cleaned up the usage of trace_uprobe_create(), and the function has been no longer used for removing uprobe/uretprobe. Link: http://lkml.kernel.org/r/20190614074026.8045-2-devel@etsukata.com Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14tracing/uprobe: Fix NULL pointer dereference in trace_uprobe_create()Eiichi Tsukata1-3/+10
Just like the case of commit 8b05a3a7503c ("tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create()"), writing an incorrectly formatted string to uprobe_events can trigger NULL pointer dereference. Reporeducer: # echo r > /sys/kernel/debug/tracing/uprobe_events dmesg: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 8000000079d12067 P4D 8000000079d12067 PUD 7b7ab067 PMD 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 1903 Comm: bash Not tainted 5.2.0-rc3+ #15 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 RIP: 0010:strchr+0x0/0x30 Code: c0 eb 0d 84 c9 74 18 48 83 c0 01 48 39 d0 74 0f 0f b6 0c 07 3a 0c 06 74 ea 19 c0 83 c8 01 c3 31 c0 c3 0f 1f 84 00 00 00 00 00 <0f> b6 07 89 f2 40 38 f0 75 0e eb 13 0f b6 47 01 48 83 c RSP: 0018:ffffb55fc0403d10 EFLAGS: 00010293 RAX: ffff993ffb793400 RBX: 0000000000000000 RCX: ffffffffa4852625 RDX: 0000000000000000 RSI: 000000000000002f RDI: 0000000000000000 RBP: ffffb55fc0403dd0 R08: ffff993ffb793400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff993ff9cc1668 R14: 0000000000000001 R15: 0000000000000000 FS: 00007f30c5147700(0000) GS:ffff993ffda00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007b628000 CR4: 00000000000006f0 Call Trace: trace_uprobe_create+0xe6/0xb10 ? __kmalloc_track_caller+0xe6/0x1c0 ? __kmalloc+0xf0/0x1d0 ? trace_uprobe_create+0xb10/0xb10 create_or_delete_trace_uprobe+0x35/0x90 ? trace_uprobe_create+0xb10/0xb10 trace_run_command+0x9c/0xb0 trace_parse_run_command+0xf9/0x1eb ? probes_open+0x80/0x80 __vfs_write+0x43/0x90 vfs_write+0x14a/0x2a0 ksys_write+0xa2/0x170 do_syscall_64+0x7f/0x200 entry_SYSCALL_64_after_hwframe+0x49/0xbe Link: http://lkml.kernel.org/r/20190614074026.8045-1-devel@etsukata.com Cc: stable@vger.kernel.org Fixes: 0597c49c69d5 ("tracing/uprobes: Use dyn_event framework for uprobe events") Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14tracing: Make two symbols staticYueHaibing1-2/+2
Fix sparse warnings: kernel/trace/trace.c:6927:24: warning: symbol 'get_tracing_log_err' was not declared. Should it be static? kernel/trace/trace.c:8196:15: warning: symbol 'trace_instance_dir' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20190614153210.24424-1-yuehaibing@huawei.com Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14tracing: avoid build warning with HAVE_NOP_MCOUNTVasily Gorbik1-3/+2
Selecting HAVE_NOP_MCOUNT enables -mnop-mcount (if gcc supports it) and sets CC_USING_NOP_MCOUNT. Reuse __is_defined (which is suitable for testing CC_USING_* defines) to avoid conditional compilation and fix the following gcc 9 warning on s390: kernel/trace/ftrace.c:2514:1: warning: ‘ftrace_code_disable’ defined but not used [-Wunused-function] Link: http://lkml.kernel.org/r/patch.git-1a82d13f33ac.your-ad-here.call-01559732716-ext-6629@work.hours Fixes: 2f4df0017baed ("tracing: Add -mcount-nop option support") Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14tracing: Fix out-of-range read in trace_stack_print()Eiichi Tsukata1-1/+1
Puts range check before dereferencing the pointer. Reproducer: # echo stacktrace > trace_options # echo 1 > events/enable # cat trace > /dev/null KASAN report: ================================================================== BUG: KASAN: use-after-free in trace_stack_print+0x26b/0x2c0 Read of size 8 at addr ffff888069d20000 by task cat/1953 CPU: 0 PID: 1953 Comm: cat Not tainted 5.2.0-rc3+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 Call Trace: dump_stack+0x8a/0xce print_address_description+0x60/0x224 ? trace_stack_print+0x26b/0x2c0 ? trace_stack_print+0x26b/0x2c0 __kasan_report.cold+0x1a/0x3e ? trace_stack_print+0x26b/0x2c0 kasan_report+0xe/0x20 trace_stack_print+0x26b/0x2c0 print_trace_line+0x6ea/0x14d0 ? tracing_buffers_read+0x700/0x700 ? trace_find_next_entry_inc+0x158/0x1d0 s_show+0xea/0x310 seq_read+0xaa7/0x10e0 ? seq_escape+0x230/0x230 __vfs_read+0x7c/0x100 vfs_read+0x16c/0x3a0 ksys_read+0x121/0x240 ? kernel_write+0x110/0x110 ? perf_trace_sys_enter+0x8a0/0x8a0 ? syscall_slow_exit_work+0xa9/0x410 do_syscall_64+0xb7/0x390 ? prepare_exit_to_usermode+0x165/0x200 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f867681f910 Code: b6 fe ff ff 48 8d 3d 0f be 08 00 48 83 ec 08 e8 06 db 01 00 66 0f 1f 44 00 00 83 3d f9 2d 2c 00 00 75 10 b8 00 00 00 00 04 RSP: 002b:00007ffdabf23488 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f867681f910 RDX: 0000000000020000 RSI: 00007f8676cde000 RDI: 0000000000000003 RBP: 00007f8676cde000 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000000871 R11: 0000000000000246 R12: 00007f8676cde000 R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000000ec0 Allocated by task 1214: save_stack+0x1b/0x80 __kasan_kmalloc.constprop.0+0xc2/0xd0 kmem_cache_alloc+0xaf/0x1a0 getname_flags+0xd2/0x5b0 do_sys_open+0x277/0x5a0 do_syscall_64+0xb7/0x390 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 1214: save_stack+0x1b/0x80 __kasan_slab_free+0x12c/0x170 kmem_cache_free+0x8a/0x1c0 putname+0xe1/0x120 do_sys_open+0x2c5/0x5a0 do_syscall_64+0xb7/0x390 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888069d20000 which belongs to the cache names_cache of size 4096 The buggy address is located 0 bytes inside of 4096-byte region [ffff888069d20000, ffff888069d21000) The buggy address belongs to the page: page:ffffea0001a74800 refcount:1 mapcount:0 mapping:ffff88806ccd1380 index:0x0 compound_mapcount: 0 flags: 0x100000000010200(slab|head) raw: 0100000000010200 dead000000000100 dead000000000200 ffff88806ccd1380 raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888069d1ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888069d1ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888069d20000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888069d20080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888069d20100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Link: http://lkml.kernel.org/r/20190610040016.5598-1-devel@etsukata.com Fixes: 4285f2fcef80 ("tracing: Remove the ULONG_MAX stack trace hackery") Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14timekeeping: Repair ktime_get_coarse*() granularityThomas Gleixner1-2/+3
Jason reported that the coarse ktime based time getters advance only once per second and not once per tick as advertised. The code reads only the monotonic base time, which advances once per second. The nanoseconds are accumulated on every tick in xtime_nsec up to a second and the regular time getters take this nanoseconds offset into account, but the ktime_get_coarse*() implementation fails to do so. Add the accumulated xtime_nsec value to the monotonic base time to get the proper per tick advancing coarse tinme. Fixes: b9ff604cff11 ("timekeeping: Add ktime_get_coarse_with_offset") Reported-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Clemens Ladisch <clemens@ladisch.de> Cc: Sultan Alsawaf <sultan@kerneltoast.com> Cc: Waiman Long <longman@redhat.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1906132136280.1791@nanos.tec.linutronix.de
2019-06-13mm/devm_memremap_pages: fix final page put raceDan Williams1-5/+12
Logan noticed that devm_memremap_pages_release() kills the percpu_ref drops all the page references that were acquired at init and then immediately proceeds to unplug, arch_remove_memory(), the backing pages for the pagemap. If for some reason device shutdown actually collides with a busy / elevated-ref-count page then arch_remove_memory() should be deferred until after that reference is dropped. As it stands the "wait for last page ref drop" happens *after* devm_memremap_pages_release() returns, which is obviously too late and can lead to crashes. Fix this situation by assigning the responsibility to wait for the percpu_ref to go idle to devm_memremap_pages() with a new ->cleanup() callback. Implement the new cleanup callback for all devm_memremap_pages() users: pmem, devdax, hmm, and p2pdma. Link: http://lkml.kernel.org/r/155727339156.292046.5432007428235387859.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: 41e94a851304 ("add devm_memremap_pages") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-13mm/devm_memremap_pages: introduce devm_memunmap_pagesDan Williams1-0/+6
Use the new devm_release_action() facility to allow devm_memremap_pages_release() to be manually triggered. Link: http://lkml.kernel.org/r/155727337088.292046.5774214552136776763.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-12cpuset: restore sanity to cpuset_cpus_allowed_fallback()Joel Savitz1-1/+14
In the case that a process is constrained by taskset(1) (i.e. sched_setaffinity(2)) to a subset of available cpus, and all of those are subsequently offlined, the scheduler will set tsk->cpus_allowed to the current value of task_cs(tsk)->effective_cpus. This is done via a call to do_set_cpus_allowed() in the context of cpuset_cpus_allowed_fallback() made by the scheduler when this case is detected. This is the only call made to cpuset_cpus_allowed_fallback() in the latest mainline kernel. However, this is not sane behavior. I will demonstrate this on a system running the latest upstream kernel with the following initial configuration: # grep -i cpu /proc/$$/status Cpus_allowed: ffffffff,fffffff Cpus_allowed_list: 0-63 (Where cpus 32-63 are provided via smt.) If we limit our current shell process to cpu2 only and then offline it and reonline it: # taskset -p 4 $$ pid 2272's current affinity mask: ffffffffffffffff pid 2272's new affinity mask: 4 # echo off > /sys/devices/system/cpu/cpu2/online # dmesg | tail -3 [ 2195.866089] process 2272 (bash) no longer affine to cpu2 [ 2195.872700] IRQ 114: no longer affine to CPU2 [ 2195.879128] smpboot: CPU 2 is now offline # echo on > /sys/devices/system/cpu/cpu2/online # dmesg | tail -1 [ 2617.043572] smpboot: Booting Node 0 Processor 2 APIC 0x4 We see that our current process now has an affinity mask containing every cpu available on the system _except_ the one we originally constrained it to: # grep -i cpu /proc/$$/status Cpus_allowed: ffffffff,fffffffb Cpus_allowed_list: 0-1,3-63 This is not sane behavior, as the scheduler can now not only place the process on previously forbidden cpus, it can't even schedule it on the cpu it was originally constrained to! Other cases result in even more exotic affinity masks. Take for instance a process with an affinity mask containing only cpus provided by smt at the moment that smt is toggled, in a configuration such as the following: # taskset -p f000000000 $$ # grep -i cpu /proc/$$/status Cpus_allowed: 000000f0,00000000 Cpus_allowed_list: 36-39 A double toggle of smt results in the following behavior: # echo off > /sys/devices/system/cpu/smt/control # echo on > /sys/devices/system/cpu/smt/control # grep -i cpus /proc/$$/status Cpus_allowed: ffffff00,ffffffff Cpus_allowed_list: 0-31,40-63 This is even less sane than the previous case, as the new affinity mask excludes all smt-provided cpus with ids less than those that were previously in the affinity mask, as well as those that were actually in the mask. With this patch applied, both of these cases end in the following state: # grep -i cpu /proc/$$/status Cpus_allowed: ffffffff,ffffffff Cpus_allowed_list: 0-63 The original policy is discarded. Though not ideal, it is the simplest way to restore sanity to this fallback case without reinventing the cpuset wheel that rolls down the kernel just fine in cgroup v2. A user who wishes for the previous affinity mask to be restored in this fallback case can use that mechanism instead. This patch modifies scheduler behavior by instead resetting the mask to task_cs(tsk)->cpus_allowed by default, and cpu_possible mask in legacy mode. I tested the cases above on both modes. Note that the scheduler uses this fallback mechanism if and only if _every_ other valid avenue has been traveled, and it is the last resort before calling BUG(). Suggested-by: Waiman Long <longman@redhat.com> Suggested-by: Phil Auld <pauld@redhat.com> Signed-off-by: Joel Savitz <jsavitz@redhat.com> Acked-by: Phil Auld <pauld@redhat.com> Acked-by: Waiman Long <longman@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-06-11Merge branch 'for-linus' of ↵Linus Torvalds2-2/+27
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull ptrace fixes from Eric Biederman: "This is just two very minor fixes: - prevent ptrace from reading unitialized kernel memory found twice by syzkaller - restore a missing smp_rmb in ptrace_may_access and add comment tp it so it is not removed by accident again. Apologies for being a little slow about getting this to you, I am still figuring out how to develop with a little baby in the house" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: ptrace: restore smp_rmb() in __ptrace_may_access() signal/ptrace: Don't leak unitialized kernel memory with PTRACE_PEEK_SIGINFO
2019-06-11ptrace: restore smp_rmb() in __ptrace_may_access()Jann Horn2-0/+19
Restore the read memory barrier in __ptrace_may_access() that was deleted a couple years ago. Also add comments on this barrier and the one it pairs with to explain why they're there (as far as I understand). Fixes: bfedb589252c ("mm: Add a user_ns owner to mm_struct and fix ptrace permission checks") Cc: stable@vger.kernel.org Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2019-06-10cgroup: Fix css_task_iter_advance_css_set() cset skip conditionTejun Heo1-1/+1
While adding handling for dying task group leaders c03cd7738a83 ("cgroup: Include dying leaders with live threads in PROCS iterations") added an inverted cset skip condition to css_task_iter_advance_css_set(). It should skip cset if it's completely empty but was incorrectly testing for the inverse condition for the dying_tasks list. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: c03cd7738a83 ("cgroup: Include dying leaders with live threads in PROCS iterations") Reported-by: syzbot+d4bba5ccd4f9a2a68681@syzkaller.appspotmail.com
2019-06-10cgroup/bfq: revert bfq.weight symlink changeJens Axboe1-29/+4
There's some discussion on how to do this the best, and Tejun prefers that BFQ just create the file itself instead of having cgroups support a symlink feature. Hence revert commit 54b7b868e826 and 19e9da9e86c4 for 5.2, and this can be done properly for 5.3. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-08Merge tag 'spdx-5.2-rc4' of ↵Linus Torvalds30-170/+30
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull yet more SPDX updates from Greg KH: "Another round of SPDX header file fixes for 5.2-rc4 These are all more "GPL-2.0-or-later" or "GPL-2.0-only" tags being added, based on the text in the files. We are slowly chipping away at the 700+ different ways people tried to write the license text. All of these were reviewed on the spdx mailing list by a number of different people. We now have over 60% of the kernel files covered with SPDX tags: $ ./scripts/spdxcheck.py -v 2>&1 | grep Files Files checked: 64533 Files with SPDX: 40392 Files with errors: 0 I think the majority of the "easy" fixups are now done, it's now the start of the longer-tail of crazy variants to wade through" * tag 'spdx-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (159 commits) treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 450 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 449 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 448 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 446 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 445 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 444 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 443 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 442 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 438 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 437 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 436 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 435 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 434 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 433 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 432 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 431 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 430 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 429 ...
2019-06-08Merge tag 'char-misc-5.2-rc4' of ↵Linus Torvalds3-31/+30
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver fixes from Greg KH: "Here are some small char and misc driver fixes for 5.2-rc4 to resolve a number of reported issues. The most "notable" one here is the kernel headers in proc^Wsysfs fixes. Those changes move the header file info into sysfs and fixes the build issues that you reported. Other than that, a bunch of small habanalabs driver fixes, some fpga driver fixes, and a few other tiny driver fixes. All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: habanalabs: Read upper bits of trace buffer from RWPHI habanalabs: Fix virtual address access via debugfs for 2MB pages fpga: zynqmp-fpga: Correctly handle error pointer habanalabs: fix bug in checking huge page optimization habanalabs: Avoid using a non-initialized MMU cache mutex habanalabs: fix debugfs code uapi/habanalabs: add opcode for enable/disable device debug mode habanalabs: halt debug engines on user process close test_firmware: Use correct snprintf() limit genwqe: Prevent an integer overflow in the ioctl parport: Fix mem leak in parport_register_dev_model fpga: dfl: expand minor range when registering chrdev region fpga: dfl: Add lockdep classes for pdata->lock fpga: dfl: afu: Pass the correct device to dma_mapping_error() fpga: stratix10-soc: fix use-after-free on s10_init() w1: ds2408: Fix typo after 49695ac46861 (reset on output_write retry with readback) kheaders: Do not regenerate archive if config is not changed kheaders: Move from proc to sysfs lkdtm/bugs: Adjust recursion test to avoid elision lkdtm/usercopy: Moves the KERNEL_DS test to non-canonical
2019-06-08Merge tag 'for-linus-20190608' of git://git.kernel.dk/linux-blockLinus Torvalds1-4/+29
Pull block fixes from Jens Axboe: - Allow symlink from the bfq.weight cgroup parameter to the general weight (Angelo) - Damien is new skd maintainer (Bart) - NVMe pull request from Sagi, with a few small fixes. - Ensure we set DMA segment size properly, dma-debug is now tripping on these (Christoph) - Remove useless debugfs_create() return check (Greg) - Remove redundant unlikely() check on IS_ERR() (Kefeng) - Fixup request freeing on exit (Ming) * tag 'for-linus-20190608' of git://git.kernel.dk/linux-block: block, bfq: add weight symlink to the bfq.weight cgroup parameter cgroup: let a symlink too be created with a cftype file block: free sched's request pool in blk_cleanup_queue nvme-rdma: use dynamic dma mapping per command nvme: Fix u32 overflow in the number of namespace list calculation mmc: also set max_segment_size in the device mtip32xx: also set max_segment_size in the device rsxx: don't call dma_set_max_seg_size nvme-pci: don't limit DMA segement size block: Drop unlikely before IS_ERR(_OR_NULL) block: aoe: no need to check return value of debugfs_create functions nvmet: fix data_len to 0 for bdev-backed write_zeroes MAINTAINERS: Hand over skd maintainership nvme-tcp: fix queue mapping when queue count is limited nvme-rdma: fix queue mapping when queue count is limited
2019-06-07Merge tag 'pm-5.2-rc4' of ↵Linus Torvalds3-2/+17
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These fix a crash during resume from hibernation introduced during the 4.19 cycle, cause the new Performance and Energy Bias Hint (EPB) code to be built only if CONFIG_PM is set and add a few missing kerneldoc comments. Specifics: - Fix a crash that occurs when a kernel with 'nosmt' in the command line is used to resume the system from hibernation (as the "restore" kernel), because memory mapping differences between the restore and image kernels cause SMT siblings to be woken up from idle states and subsequently they try to fetch instructions from incorrect memory locations (Jiri Kosina). - Cause the new Performance and Energy Bias Hint (EPB) code to be built only if CONFIG_PM is set, because that code is not really necessary otherwise (Rafael Wysocki). - Add kerneldoc comments to documents some helper functions related to system-wide suspend to avoid possible confusion regarding their purpose (Rafael Wysocki)" * tag 'pm-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: x86/power: Fix 'nosmt' vs hibernation triple fault during resume PM: sleep: Add kerneldoc comments to some functions x86: intel_epb: Do not build when CONFIG_PM is unset
2019-06-07Merge branch 'pm-x86'Rafael J. Wysocki2-2/+11
* pm-x86: x86/power: Fix 'nosmt' vs hibernation triple fault during resume x86: intel_epb: Do not build when CONFIG_PM is unset
2019-06-07cgroup: let a symlink too be created with a cftype fileAngelo Ruocco1-4/+29
This commit enables a cftype to have a symlink (of any name) that points to the file associated with the cftype. Signed-off-by: Angelo Ruocco <angeloruocco90@gmail.com> Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-05cgroup: css_task_iter_skip()'d iterators must be advanced before accessedTejun Heo1-0/+4
b636fd38dc40 ("cgroup: Implement css_task_iter_skip()") introduced css_task_iter_skip() which is used to fix task iterations skipping dying threadgroup leaders with live threads. Skipping is implemented as a subportion of full advancing but css_task_iter_next() forgot to fully advance a skipped iterator before determining the next task to visit causing it to return invalid task pointers. Fix it by making css_task_iter_next() fully advance the iterator if it has been skipped since the previous iteration. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: syzbot Link: http://lkml.kernel.org/r/00000000000097025d058a7fd785@google.com Fixes: b636fd38dc40 ("cgroup: Implement css_task_iter_skip()")
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441Thomas Gleixner10-52/+10
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 of the license extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 315 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 436Thomas Gleixner1-2/+1
Based on 1 normalized pattern(s): distributed under the terms of the gnu gpl version 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 2 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190115.032570679@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 430Thomas Gleixner1-2/+1
Based on 1 normalized pattern(s): distribute under gplv2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 8 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190114.475576622@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428Thomas Gleixner7-18/+7
Based on 1 normalized pattern(s): this file is released under the gplv2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 68 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 363Thomas Gleixner1-1/+1
Based on 1 normalized pattern(s): released under terms in gpl version 2 see copying extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 5 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531081035.689962394@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333Thomas Gleixner1-13/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 136 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295Thomas Gleixner8-72/+8
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 64 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.894819585@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282Thomas Gleixner1-10/+1
Based on 1 normalized pattern(s): this software is licensed under the terms of the gnu general public license version 2 as published by the free software foundation and may be copied distributed and modified under those terms this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 285 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05signal: improve commentsChristian Brauner1-6/+5
Improve the comments for pidfd_send_signal(). First, the comment still referred to a file descriptor for a process as a "task file descriptor" which stems from way back at the beginning of the discussion. Replace this with "pidfd" for consistency. Second, the wording for the explanation of the arguments to the syscall was a bit inconsistent, e.g. some used the past tense some used present tense. Make the wording more consistent. Signed-off-by: Christian Brauner <christian@brauner.io>
2019-06-03locking/lock_events: Use raw_cpu_{add,inc}() for statsPeter Zijlstra1-41/+4
Instead of playing silly games with CONFIG_DEBUG_PREEMPT toggling between this_cpu_*() and __this_cpu_*() use raw_cpu_*(), which is exactly what we want here. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: huang ying <huang.ying.caritas@gmail.com> Link: https://lkml.kernel.org/r/20190527082326.GP2623@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Fix merging of hlocks with non-zero referencesImre Deak1-9/+9
The sequence static DEFINE_WW_CLASS(test_ww_class); struct ww_acquire_ctx ww_ctx; struct ww_mutex ww_lock_a; struct ww_mutex ww_lock_b; struct ww_mutex ww_lock_c; struct mutex lock_c; ww_acquire_init(&ww_ctx, &test_ww_class); ww_mutex_init(&ww_lock_a, &test_ww_class); ww_mutex_init(&ww_lock_b, &test_ww_class); ww_mutex_init(&ww_lock_c, &test_ww_class); mutex_init(&lock_c); ww_mutex_lock(&ww_lock_a, &ww_ctx); mutex_lock(&lock_c); ww_mutex_lock(&ww_lock_b, &ww_ctx); ww_mutex_lock(&ww_lock_c, &ww_ctx); mutex_unlock(&lock_c); (*) ww_mutex_unlock(&ww_lock_c); ww_mutex_unlock(&ww_lock_b); ww_mutex_unlock(&ww_lock_a); ww_acquire_fini(&ww_ctx); (**) will trigger the following error in __lock_release() when calling mutex_release() at **: DEBUG_LOCKS_WARN_ON(depth <= 0) The problem is that the hlock merging happening at * updates the references for test_ww_class incorrectly to 3 whereas it should've updated it to 4 (representing all the instances for ww_ctx and ww_lock_[abc]). Fix this by updating the references during merging correctly taking into account that we can have non-zero references (both for the hlock that we merge into another hlock or for the hlock we are merging into). Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190524201509.9199-2-imre.deak@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Fix OOO unlock when hlocks need mergingImre Deak1-12/+29
The sequence static DEFINE_WW_CLASS(test_ww_class); struct ww_acquire_ctx ww_ctx; struct ww_mutex ww_lock_a; struct ww_mutex ww_lock_b; struct mutex lock_c; struct mutex lock_d; ww_acquire_init(&ww_ctx, &test_ww_class); ww_mutex_init(&ww_lock_a, &test_ww_class); ww_mutex_init(&ww_lock_b, &test_ww_class); mutex_init(&lock_c); ww_mutex_lock(&ww_lock_a, &ww_ctx); mutex_lock(&lock_c); ww_mutex_lock(&ww_lock_b, &ww_ctx); mutex_unlock(&lock_c); (*) ww_mutex_unlock(&ww_lock_b); ww_mutex_unlock(&ww_lock_a); ww_acquire_fini(&ww_ctx); triggers the following WARN in __lock_release() when doing the unlock at *: DEBUG_LOCKS_WARN_ON(curr->lockdep_depth != depth - 1); The problem is that the WARN check doesn't take into account the merging of ww_lock_a and ww_lock_b which results in decreasing curr->lockdep_depth by 2 not only 1. Note that the following sequence doesn't trigger the WARN, since there won't be any hlock merging. ww_acquire_init(&ww_ctx, &test_ww_class); ww_mutex_init(&ww_lock_a, &test_ww_class); ww_mutex_init(&ww_lock_b, &test_ww_class); mutex_init(&lock_c); mutex_init(&lock_d); ww_mutex_lock(&ww_lock_a, &ww_ctx); mutex_lock(&lock_c); mutex_lock(&lock_d); ww_mutex_lock(&ww_lock_b, &ww_ctx); mutex_unlock(&lock_d); ww_mutex_unlock(&ww_lock_b); ww_mutex_unlock(&ww_lock_a); mutex_unlock(&lock_c); ww_acquire_fini(&ww_ctx); In general both of the above two sequences are valid and shouldn't trigger any lockdep warning. Fix this by taking the decrement due to the hlock merging into account during lock release and hlock class re-setting. Merging can't happen during lock downgrading since there won't be a new possibility to merge hlocks in that case, so add a WARN if merging still happens then. Signed-off-by: Imre Deak <imre.deak@intel.com> 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: Will Deacon <will.deacon@arm.com> Cc: ville.syrjala@linux.intel.com Link: https://lkml.kernel.org/r/20190524201509.9199-1-imre.deak@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03x86/power: Fix 'nosmt' vs hibernation triple fault during resumeJiri Kosina2-2/+11
As explained in 0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once") we always, no matter what, have to bring up x86 HT siblings during boot at least once in order to avoid first MCE bringing the system to its knees. That means that whenever 'nosmt' is supplied on the kernel command-line, all the HT siblings are as a result sitting in mwait or cpudile after going through the online-offline cycle at least once. This causes a serious issue though when a kernel, which saw 'nosmt' on its commandline, is going to perform resume from hibernation: if the resume from the hibernated image is successful, cr3 is flipped in order to point to the address space of the kernel that is being resumed, which in turn means that all the HT siblings are all of a sudden mwaiting on address which is no longer valid. That results in triple fault shortly after cr3 is switched, and machine reboots. Fix this by always waking up all the SMT siblings before initiating the 'restore from hibernation' process; this guarantees that all the HT siblings will be properly carried over to the resumed kernel waiting in resume_play_dead(), and acted upon accordingly afterwards, based on the target kernel configuration. Symmetricaly, the resumed kernel has to push the SMT siblings to mwait again in case it has SMT disabled; this means it has to online all the siblings when resuming (so that they come out of hlt) and offline them again to let them reach mwait. Cc: 4.19+ <stable@vger.kernel.org> # v4.19+ Debugged-by: Thomas Gleixner <tglx@linutronix.de> Fixes: 0cc3cd21657b ("cpu/hotplug: Boot HT siblings at least once") Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Pavel Machek <pavel@ucw.cz> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-06-03locking/lockdep: Remove !dir in lock irq usage checkYuyang Du1-1/+1
In mark_lock_irq(), the following checks are performed: ---------------------------------- | -> | unsafe | read unsafe | |----------------------------------| | safe | F B | F* B* | |----------------------------------| | read safe | F? B* | - | ---------------------------------- Where: F: check_usage_forwards B: check_usage_backwards *: check enabled by STRICT_READ_CHECKS ?: check enabled by the !dir condition From checking point of view, the special F? case does not make sense, whereas it perhaps is made for peroformance concern. As later patch will address this issue, remove this exception, which makes the checks consistent later. With STRICT_READ_CHECKS = 1 which is default, there is no functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-24-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Adjust new bit cases in mark_lockYuyang Du1-14/+7
The new bit can be any possible lock usage except it is garbage, so the cases in switch can be made simpler. Warn early on if wrong usage bit is passed without taking locks. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-23-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Consolidate lock usage bit initializationYuyang Du1-8/+14
Lock usage bit initialization is consolidated into one function mark_usage(). Trivial readability improvement. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-22-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Check redundant dependency only when CONFIG_LOCKDEP_SMALLYuyang Du1-0/+4
As Peter has put it all sound and complete for the cause, I simply quote: "It (check_redundant) was added for cross-release (which has since been reverted) which would generate a lot of redundant links (IIRC) but having it makes the reports more convoluted -- basically, if we had an A-B-C relation, then A-C will not be added to the graph because it is already covered. This then means any report will include B, even though a shorter cycle might have been possible." This would increase the number of direct dependencies. For a simple workload (make clean; reboot; make vmlinux -j8), the data looks like this: CONFIG_LOCKDEP_SMALL: direct dependencies: 6926 !CONFIG_LOCKDEP_SMALL: direct dependencies: 9052 (+30.7%) Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-21-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Refactorize check_noncircular and check_redundantYuyang Du1-44/+74
These two functions now handle different check results themselves. A new check_path function is added to check whether there is a path in the dependency graph. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-20-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Remove unused argument in __lock_releaseYuyang Du1-2/+2
The @nested is not used in __release_lock so remove it despite that it is not used in lock_release in the first place. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-19-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Remove redundant argument in check_deadlockYuyang Du1-3/+3
In check_deadlock(), the third argument read comes from the second argument hlock so that it can be removed. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-18-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Update comments on dependency searchYuyang Du1-11/+10
The breadth-first search is implemented as flat-out non-recursive now, but the comments are still describing it as recursive, update the comments in that regard. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-16-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Avoid constant checks in __bfs by using offset referenceYuyang Du1-12/+21
In search of a dependency in the lock graph, there is contant checks for forward or backward search. Directly reference the field offset of the struct that differentiates the type of search to avoid those checks. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-15-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03locking/lockdep: Change the return type of __cq_dequeue()Yuyang Du1-8/+13
With the change, we can slightly adjust the code to iterate the queue in BFS search, which simplifies the code. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> 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: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-14-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>