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2022-10-03Merge tag 'pm-6.1-rc1' of ↵Linus Torvalds1-15/+15
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add support for some new hardware, extend the existing hardware support, fix some issues and clean up code Specifics: - Add isupport for Tiger Lake in no-HWP mode to intel_pstate (Doug Smythies) - Update the AMD P-state driver (Perry Yuan): - Fix wrong lowest perf fetch - Map desired perf into pstate scope for powersave governor - Update pstate frequency transition delay time - Fix initial highest_perf value - Clean up - Move max CPU capacity to sugov_policy in the schedutil cpufreq governor (Lukasz Luba) - Add SM6115 to cpufreq-dt blocklist (Adam Skladowski) - Add support for Tegra239 and minor cleanups (Sumit Gupta, ye xingchen, and Yang Yingliang) - Add freq qos for qcom cpufreq driver and minor cleanups (Xuewen Yan, and Viresh Kumar) - Minor cleanups around functions called at module_init() (Xiu Jianfeng) - Use module_init and add module_exit for bmips driver (Zhang Jianhua) - Add AlderLake-N support to intel_idle (Zhang Rui) - Replace strlcpy() with unused retval with strscpy() in intel_idle (Wolfram Sang) - Remove redundant check from cpuidle_switch_governor() (Yu Liao) - Replace strlcpy() with unused retval with strscpy() in the powernv cpuidle driver (Wolfram Sang) - Drop duplicate word from a comment in the coupled cpuidle driver (Jason Wang) - Make rpm_resume() return -EINPROGRESS if RPM_NOWAIT is passed to it in the flags and the device is about to resume (Rafael Wysocki) - Add extra debugging statement for multiple active IRQs to system wakeup handling code (Mario Limonciello) - Replace strlcpy() with unused retval with strscpy() in the core system suspend support code (Wolfram Sang) - Update the intel_rapl power capping driver: - Use standard Energy Unit for SPR Dram RAPL domain (Zhang Rui). - Add support for RAPTORLAKE_S (Zhang Rui). - Fix UBSAN shift-out-of-bounds issue (Chao Qin) - Handle -EPROBE_DEFER when regulator is not probed on mtk-ci-devfreq.c (AngeloGioacchino Del Regno) - Fix message typo and use dev_err_probe() in rockchip-dfi.c (Christophe JAILLET)" * tag 'pm-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (29 commits) cpufreq: qcom-cpufreq-hw: Add cpufreq qos for LMh cpufreq: Add __init annotation to module init funcs cpufreq: tegra194: change tegra239_cpufreq_soc to static PM / devfreq: rockchip-dfi: Fix an error message PM / devfreq: mtk-cci: Handle sram regulator probe deferral powercap: intel_rapl: Use standard Energy Unit for SPR Dram RAPL domain PM: runtime: Return -EINPROGRESS from rpm_resume() in the RPM_NOWAIT case intel_idle: Add AlderLake-N support powercap: intel_rapl: fix UBSAN shift-out-of-bounds issue cpufreq: tegra194: Add support for Tegra239 cpufreq: qcom-cpufreq-hw: Fix uninitialized throttled_freq warning cpufreq: intel_pstate: Add Tigerlake support in no-HWP mode powercap: intel_rapl: Add support for RAPTORLAKE_S cpufreq: amd-pstate: Fix initial highest_perf value cpuidle: Remove redundant check in cpuidle_switch_governor() PM: wakeup: Add extra debugging statement for multiple active IRQs cpufreq: tegra194: Remove the unneeded result variable PM: suspend: move from strlcpy() with unused retval to strscpy() intel_idle: move from strlcpy() with unused retval to strscpy() cpuidle: powernv: move from strlcpy() with unused retval to strscpy() ...
2022-10-03Merge branch 'pm-cpufreq'Rafael J. Wysocki1-15/+15
Merge cpufreq changes for 6.1-rc1: - Add isupport for Tiger Lake in no-HWP mode to intel_pstate (Doug Smythies). - Update the AMD P-state driver (Perry Yuan): * Fix wrong lowest perf fetch. * Map desired perf into pstate scope for powersave governor. * Update pstate frequency transition delay time. * Fix initial highest_perf value. * Clean up. - Move max CPU capacity to sugov_policy in the schedutil cpufreq governor (Lukasz Luba). - Add SM6115 to cpufreq-dt blocklist (Adam Skladowski). - Add support for Tegra239 and minor cleanups (Sumit Gupta, ye xingchen, and Yang Yingliang). - Add freq qos for qcom cpufreq driver and minor cleanups (Xuewen Yan, and Viresh Kumar). - Minor cleanups around functions called at module_init() (Xiu Jianfeng). - Use module_init and add module_exit for bmips driver (Zhang Jianhua). * pm-cpufreq: cpufreq: qcom-cpufreq-hw: Add cpufreq qos for LMh cpufreq: Add __init annotation to module init funcs cpufreq: tegra194: change tegra239_cpufreq_soc to static cpufreq: tegra194: Add support for Tegra239 cpufreq: qcom-cpufreq-hw: Fix uninitialized throttled_freq warning cpufreq: intel_pstate: Add Tigerlake support in no-HWP mode cpufreq: amd-pstate: Fix initial highest_perf value cpufreq: tegra194: Remove the unneeded result variable cpufreq: amd-pstate: update pstate frequency transition delay time cpufreq: amd_pstate: map desired perf into pstate scope for powersave governor cpufreq: amd_pstate: fix wrong lowest perf fetch cpufreq: amd-pstate: fix white-space cpufreq: amd-pstate: simplify cpudata pointer assignment cpufreq: bmips-cpufreq: Use module_init and add module_exit cpufreq: schedutil: Move max CPU capacity to sugov_policy cpufreq: Add SM6115 to cpufreq-dt-platdev blocklist
2022-10-03Merge tag 'rcu.2022.09.30a' of ↵Linus Torvalds11-153/+628
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu Pull RCU updates from Paul McKenney: - Documentation updates. This is the first in a series from an ongoing review of the RCU documentation. "Why are people thinking -that- about RCU? Oh. Because that is an entirely reasonable interpretation of its documentation." - Miscellaneous fixes. - Improved memory allocation and heuristics. - Improve rcu_nocbs diagnostic output. - Add full-sized polled RCU grace period state values. These are the same size as an rcu_head structure, which is double that of the traditional unsigned long state values that may still be obtained from et_state_synchronize_rcu(). The added size avoids missing overlapping grace periods. This benefit is that call_rcu() can be replaced by polling, which can be attractive in situations where RCU-protected data is aged out of memory. Early in the series, the size of this state value is three unsigned longs. Later in the series, the fastpaths in synchronize_rcu() and synchronize_rcu_expedited() are reworked to permit the full state to be represented by only two unsigned longs. This reworking slows these two functions down in SMP kernels running either on single-CPU systems or on systems with all but one CPU offlined, but this should not be a significant problem. And if it somehow becomes a problem in some yet-as-unforeseen situations, three-value state values can be provided for only those situations. Finally, a pair of functions named same_state_synchronize_rcu() and same_state_synchronize_rcu_full() allow grace-period state values to be compared for equality. This permits users to maintain lists of data structures having the same state value, removing the need for per-data-structure grace-period state values, thus decreasing memory footprint. - Polled SRCU grace-period updates, including adding tests to rcutorture and reducing the incidence of Tiny SRCU grace-period-state counter wrap. - Improve Tasks RCU diagnostics and quiescent-state detection. * tag 'rcu.2022.09.30a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (55 commits) rcutorture: Use the barrier operation specified by cur_ops rcu-tasks: Make RCU Tasks Trace check for userspace execution rcu-tasks: Ensure RCU Tasks Trace loops have quiescent states rcu-tasks: Convert RCU_LOCKDEP_WARN() to WARN_ONCE() srcu: Make Tiny SRCU use full-sized grace-period counters srcu: Make Tiny SRCU poll_state_synchronize_srcu() more precise srcu: Add GP and maximum requested GP to Tiny SRCU rcutorture output rcutorture: Make "srcud" option also test polled grace-period API rcutorture: Limit read-side polling-API testing rcu: Add functions to compare grace-period state values rcutorture: Expand rcu_torture_write_types() first "if" statement rcutorture: Use 1-suffixed variable in rcu_torture_write_types() check rcu: Make synchronize_rcu() fastpath update only boot-CPU counters rcutorture: Adjust rcu_poll_need_2gp() for rcu_gp_oldstate field removal rcu: Remove ->rgos_polled field from rcu_gp_oldstate structure rcu: Make synchronize_rcu_expedited() fast path update .expedited_sequence rcu: Remove expedited grace-period fast-path forward-progress helper rcu: Make synchronize_rcu() fast path update ->gp_seq counters rcu-tasks: Remove grace-period fast-path rcu-tasks helper rcu: Set rcu_data structures' initial ->gpwrap value to true ...
2022-10-02Merge tag 'perf-urgent-2022-10-02' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc perf fixes from Ingo Molnar: - Fix a PMU enumeration/initialization bug on Intel Alder Lake CPUs - Fix KVM guest PEBS register handling - Fix race/reentry bug in perf_output_read_group() reading of PMU counters * tag 'perf-urgent-2022-10-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Fix reentry problem in perf_output_read_group() perf/x86/core: Completely disable guest PEBS via guest's global_ctrl perf/x86/intel: Fix unchecked MSR access error for Alder Lake N
2022-09-24Merge tag 'cgroup-for-6.0-rc6-fixes' of ↵Linus Torvalds1-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: - Add Waiman Long as a cpuset maintainer - cgroup_get_from_id() could be fed a kernfs ID which doesn't point to a cgroup directory but a knob file and then crash. Error out if the lookup kernfs_node isn't a directory. * tag 'cgroup-for-6.0-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: cgroup_get_from_id() must check the looked-up kn is a directory cpuset: Add Waiman Long as a cpuset maintainer
2022-09-24Merge tag 'wq-for-6.0-rc6-fixes' of ↵Linus Torvalds1-4/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue fix from Tejun Heo: "Just one patch to improve flush lockdep coverage" * tag 'wq-for-6.0-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: don't skip lockdep work dependency in cancel_work_sync()
2022-09-23cgroup: cgroup_get_from_id() must check the looked-up kn is a directoryMing Lei1-1/+4
cgroup has to be one kernfs dir, otherwise kernel panic is caused, especially cgroup id is provide from userspace. Reported-by: Marco Patalano <mpatalan@redhat.com> Fixes: 6b658c4863c1 ("scsi: cgroup: Add cgroup_get_from_id()") Cc: Muneendra <muneendra.kumar@broadcom.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Acked-by: Mukesh Ojha <quic_mojha@quicinc.com> Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Tejun Heo <tj@kernel.org>
2022-09-20Merge tag 'execve-v6.0-rc7' of ↵Linus Torvalds2-6/+2
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull execve reverts from Kees Cook: "The recent work to support time namespace unsharing turns out to have some undesirable corner cases, so rather than allowing the API to stay exposed for another release, it'd be best to remove it ASAP, with the replacement getting another cycle of testing. Nothing is known to use this yet, so no userspace breakage is expected. For more details, see: https://lore.kernel.org/lkml/ed418e43ad28b8688cfea2b7c90fce1c@ispras.ru Summary: - Remove the recent 'unshare time namespace on vfork+exec' feature (Andrei Vagin)" * tag 'execve-v6.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: Revert "fs/exec: allow to unshare a time namespace on vfork+exec" Revert "selftests/timens: add a test for vfork+exit"
2022-09-13Revert "fs/exec: allow to unshare a time namespace on vfork+exec"Andrei Vagin2-6/+2
This reverts commit 133e2d3e81de5d9706cab2dd1d52d231c27382e5. Alexey pointed out a few undesirable side effects of the reverted change. First, it doesn't take into account that CLONE_VFORK can be used with CLONE_THREAD. Second, a child process doesn't enter a target time name-space, if its parent dies before the child calls exec. It happens because the parent clears vfork_done. Eric W. Biederman suggests installing a time namespace as a task gets a new mm. It includes all new processes cloned without CLONE_VM and all tasks that call exec(). This is an user API change, but we think there aren't users that depend on the old behavior. It is too late to make such changes in this release, so let's roll back this patch and introduce the right one in the next release. Cc: Alexey Izbyshev <izbyshev@ispras.ru> Cc: Christian Brauner <brauner@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220913102551.1121611-3-avagin@google.com
2022-09-10Merge tag 'dma-mapping-6.0-2022-09-10' of ↵Linus Torvalds3-13/+9
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping fixes from Christoph Hellwig: - revert a panic on swiotlb initialization failure (Yu Zhao) - fix the lookup for partial syncs in dma-debug (Robin Murphy) - fix a shift overflow in swiotlb (Chao Gao) - fix a comment typo in swiotlb (Chao Gao) - mark a function static now that all abusers are gone (Christoph Hellwig) * tag 'dma-mapping-6.0-2022-09-10' of git://git.infradead.org/users/hch/dma-mapping: dma-mapping: mark dma_supported static swiotlb: fix a typo swiotlb: avoid potential left shift overflow dma-debug: improve search for partial syncs Revert "swiotlb: panic if nslabs is too small"
2022-09-09Merge tag 'driver-core-6.0-rc5' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core fixes from Greg KH: "Here are some small driver core and debugfs fixes for 6.0-rc5. Included in here are: - multiple attempts to get the arch_topology code to work properly on non-cluster SMT systems. First attempt caused build breakages in linux-next and 0-day, second try worked. - debugfs fixes for a long-suffering memory leak. The pattern of debugfs_remove(debugfs_lookup(...)) turns out to leak dentries, so add debugfs_lookup_and_remove() to fix this problem. Also fix up the scheduler debug code that highlighted this problem. Fixes for other subsystems will be trickling in over the next few months for this same issue once the debugfs function is merged. All of these have been in linux-next since Wednesday with no reported problems" * tag 'driver-core-6.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: arch_topology: Make cluster topology span at least SMT CPUs sched/debug: fix dentry leak in update_sched_domain_debugfs debugfs: add debugfs_lookup_and_remove() driver core: fix driver_set_override() issue with empty strings Revert "arch_topology: Make cluster topology span at least SMT CPUs" arch_topology: Make cluster topology span at least SMT CPUs
2022-09-09Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds1-0/+1
Pull rdma fixes from Jason Gunthorpe: "Many bug fixes in several drivers: - Fix misuse of the DMA API in rtrs - Several irdma issues: hung task due to SQ flushing, incorrect capability reporting to userspace, improper error handling for MW corners, touching an uninitialized SGL for during invalidation. - hns was using the wrong page size limits for the HW, an incorrect calculation of wqe_shift causing WQE corruption, and mis computed a timer id. - Fix a crash in SRP triggered by blktests - Fix compiler errors by calling virt_to_page() with the proper type in siw - Userspace triggerable deadlock in ODP - mlx5 could use the wrong profile due to some driver loading races, counters were not working in some device configurations, and a crash on error unwind" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: RDMA/irdma: Report RNR NAK generation in device caps RDMA/irdma: Use s/g array in post send only when its valid RDMA/irdma: Return correct WC error for bind operation failure RDMA/irdma: Return error on MR deregister CQP failure RDMA/irdma: Report the correct max cqes from query device MAINTAINERS: Update maintainers of HiSilicon RoCE RDMA/mlx5: Fix UMR cleanup on error flow of driver init RDMA/mlx5: Set local port to one when accessing counters RDMA/mlx5: Rely on RoCE fw cap instead of devlink when setting profile IB/core: Fix a nested dead lock as part of ODP flow RDMA/siw: Pass a pointer to virt_to_page() RDMA/srp: Set scmnd->result only when scmnd is not NULL RDMA/hns: Remove the num_qpc_timer variable RDMA/hns: Fix wrong fixed value of qp->rq.wqe_shift RDMA/hns: Fix supported page size RDMA/cma: Fix arguments order in net device validation RDMA/irdma: Fix drain SQ hang with no completion RDMA/rtrs-srv: Pass the correct number of entries for dma mapped SGL RDMA/rtrs-clt: Use the right sg_cnt after ib_dma_map_sg
2022-09-08kprobes: Prohibit probes in gate areaChristian A. Ehrhardt1-0/+1
The system call gate area counts as kernel text but trying to install a kprobe in this area fails with an Oops later on. To fix this explicitly disallow the gate area for kprobes. Found by syzkaller with the following reproducer: perf_event_open$cgroup(&(0x7f00000001c0)={0x6, 0x80, 0x0, 0x0, 0x0, 0x0, 0x80ffff, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, @perf_config_ext={0x0, 0xffffffffff600000}}, 0xffffffffffffffff, 0x0, 0xffffffffffffffff, 0x0) Sample report: BUG: unable to handle page fault for address: fffffbfff3ac6000 PGD 6dfcb067 P4D 6dfcb067 PUD 6df8f067 PMD 6de4d067 PTE 0 Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 0 PID: 21978 Comm: syz-executor.2 Not tainted 6.0.0-rc3-00363-g7726d4c3e60b-dirty #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:__insn_get_emulate_prefix arch/x86/lib/insn.c:91 [inline] RIP: 0010:insn_get_emulate_prefix arch/x86/lib/insn.c:106 [inline] RIP: 0010:insn_get_prefixes.part.0+0xa8/0x1110 arch/x86/lib/insn.c:134 Code: 49 be 00 00 00 00 00 fc ff df 48 8b 40 60 48 89 44 24 08 e9 81 00 00 00 e8 e5 4b 39 ff 4c 89 fa 4c 89 f9 48 c1 ea 03 83 e1 07 <42> 0f b6 14 32 38 ca 7f 08 84 d2 0f 85 06 10 00 00 48 89 d8 48 89 RSP: 0018:ffffc900088bf860 EFLAGS: 00010246 RAX: 0000000000040000 RBX: ffffffff9b9bebc0 RCX: 0000000000000000 RDX: 1ffffffff3ac6000 RSI: ffffc90002d82000 RDI: ffffc900088bf9e8 RBP: ffffffff9d630001 R08: 0000000000000000 R09: ffffc900088bf9e8 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: ffffffff9d630000 R14: dffffc0000000000 R15: ffffffff9d630000 FS: 00007f63eef63640(0000) GS:ffff88806d000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: fffffbfff3ac6000 CR3: 0000000029d90005 CR4: 0000000000770ef0 PKRU: 55555554 Call Trace: <TASK> insn_get_prefixes arch/x86/lib/insn.c:131 [inline] insn_get_opcode arch/x86/lib/insn.c:272 [inline] insn_get_modrm+0x64a/0x7b0 arch/x86/lib/insn.c:343 insn_get_sib+0x29a/0x330 arch/x86/lib/insn.c:421 insn_get_displacement+0x350/0x6b0 arch/x86/lib/insn.c:464 insn_get_immediate arch/x86/lib/insn.c:632 [inline] insn_get_length arch/x86/lib/insn.c:707 [inline] insn_decode+0x43a/0x490 arch/x86/lib/insn.c:747 can_probe+0xfc/0x1d0 arch/x86/kernel/kprobes/core.c:282 arch_prepare_kprobe+0x79/0x1c0 arch/x86/kernel/kprobes/core.c:739 prepare_kprobe kernel/kprobes.c:1160 [inline] register_kprobe kernel/kprobes.c:1641 [inline] register_kprobe+0xb6e/0x1690 kernel/kprobes.c:1603 __register_trace_kprobe kernel/trace/trace_kprobe.c:509 [inline] __register_trace_kprobe+0x26a/0x2d0 kernel/trace/trace_kprobe.c:477 create_local_trace_kprobe+0x1f7/0x350 kernel/trace/trace_kprobe.c:1833 perf_kprobe_init+0x18c/0x280 kernel/trace/trace_event_perf.c:271 perf_kprobe_event_init+0xf8/0x1c0 kernel/events/core.c:9888 perf_try_init_event+0x12d/0x570 kernel/events/core.c:11261 perf_init_event kernel/events/core.c:11325 [inline] perf_event_alloc.part.0+0xf7f/0x36a0 kernel/events/core.c:11619 perf_event_alloc kernel/events/core.c:12059 [inline] __do_sys_perf_event_open+0x4a8/0x2a00 kernel/events/core.c:12157 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f63ef7efaed Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f63eef63028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f63ef90ff80 RCX: 00007f63ef7efaed RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 00000000200001c0 RBP: 00007f63ef86019c R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000002 R14: 00007f63ef90ff80 R15: 00007f63eef43000 </TASK> Modules linked in: CR2: fffffbfff3ac6000 ---[ end trace 0000000000000000 ]--- RIP: 0010:__insn_get_emulate_prefix arch/x86/lib/insn.c:91 [inline] RIP: 0010:insn_get_emulate_prefix arch/x86/lib/insn.c:106 [inline] RIP: 0010:insn_get_prefixes.part.0+0xa8/0x1110 arch/x86/lib/insn.c:134 Code: 49 be 00 00 00 00 00 fc ff df 48 8b 40 60 48 89 44 24 08 e9 81 00 00 00 e8 e5 4b 39 ff 4c 89 fa 4c 89 f9 48 c1 ea 03 83 e1 07 <42> 0f b6 14 32 38 ca 7f 08 84 d2 0f 85 06 10 00 00 48 89 d8 48 89 RSP: 0018:ffffc900088bf860 EFLAGS: 00010246 RAX: 0000000000040000 RBX: ffffffff9b9bebc0 RCX: 0000000000000000 RDX: 1ffffffff3ac6000 RSI: ffffc90002d82000 RDI: ffffc900088bf9e8 RBP: ffffffff9d630001 R08: 0000000000000000 R09: ffffc900088bf9e8 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: ffffffff9d630000 R14: dffffc0000000000 R15: ffffffff9d630000 FS: 00007f63eef63640(0000) GS:ffff88806d000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: fffffbfff3ac6000 CR3: 0000000029d90005 CR4: 0000000000770ef0 PKRU: 55555554 ================================================================== Link: https://lkml.kernel.org/r/20220907200917.654103-1-lk@c--e.de cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> cc: "David S. Miller" <davem@davemloft.net> Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Christian A. Ehrhardt <lk@c--e.de> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-07dma-mapping: mark dma_supported staticChristoph Hellwig1-2/+1
Now that the remaining users in drivers are gone, this function can be marked static. Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-09-07swiotlb: fix a typoChao Gao1-1/+1
"overwirte" isn't a word. It should be "overwrite". Signed-off-by: Chao Gao <chao.gao@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-09-07swiotlb: avoid potential left shift overflowChao Gao1-1/+4
The second operand passed to slot_addr() is declared as int or unsigned int in all call sites. The left-shift to get the offset of a slot can overflow if swiotlb size is larger than 4G. Convert the macro to an inline function and declare the second argument as phys_addr_t to avoid the potential overflow. Fixes: 26a7e094783d ("swiotlb: refactor swiotlb_tbl_map_single") Signed-off-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-09-07dma-debug: improve search for partial syncsRobin Murphy1-4/+2
When bucket_find_contains() tries to find the original entry for a partial sync, it manages to constrain its search in a way that is both too restrictive and not restrictive enough. A driver which only uses single mappings rather than scatterlists might not set max_seg_size, but could still technically perform a partial sync at an offset of more than 64KB into a sufficiently large mapping, so we could stop searching too early before reaching a legitimate entry. Conversely, if no valid entry is present and max_range is large enough, we can pointlessly search buckets that we've already searched, or that represent an impossible wrapping around the bottom of the address space. At worst, the (legitimate) case of max_seg_size == UINT_MAX can make the loop infinite. Replace the fragile and frankly hard-to-follow "range" logic with a simple counted loop for the number of possible hash buckets below the given address. Reported-by: Yunfei Wang <yf.wang@mediatek.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-09-07Revert "swiotlb: panic if nslabs is too small"Yu Zhao1-5/+1
This reverts commit 0bf28fc40d89b1a3e00d1b79473bad4e9ca20ad1. Reasons: 1. new panic()s shouldn't be added [1]. 2. It does no "cleanup" but breaks MIPS [2]. v2: properly solved the conflict [3] with commit 20347fca71a38 ("swiotlb: split up the global swiotlb lock") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> [1] https://lore.kernel.org/r/CAHk-=wit-DmhMfQErY29JSPjFgebx_Ld+pnerc4J2Ag990WwAA@mail.gmail.com/ [2] https://lore.kernel.org/r/20220820012031.1285979-1-yuzhao@google.com/ [3] https://lore.kernel.org/r/202208310701.LKr1WDCh-lkp@intel.com/ Fixes: 0bf28fc40d89b ("swiotlb: panic if nslabs is too small") Signed-off-by: Yu Zhao <yuzhao@google.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-09-06rv/reactor: add __init/__exit annotations to module init/exit funcsXiu Jianfeng2-4/+4
Add missing __init/__exit annotations to module init/exit funcs. Link: https://lkml.kernel.org/r/20220906141210.132607-1-xiujianfeng@huawei.com Fixes: 135b881ea885 ("rv/reactor: Add the printk reactor") Fixes: e88043c0ac16 ("rv/reactor: Add the panic reactor") Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-06tracing: Fix to check event_mutex is held while accessing trigger listMasami Hiramatsu (Google)1-1/+2
Since the check_user_trigger() is called outside of RCU read lock, this list_for_each_entry_rcu() caused a suspicious RCU usage warning. # echo hist:keys=pid > events/sched/sched_stat_runtime/trigger # cat events/sched/sched_stat_runtime/trigger [ 43.167032] [ 43.167418] ============================= [ 43.167992] WARNING: suspicious RCU usage [ 43.168567] 5.19.0-rc5-00029-g19ebe4651abf #59 Not tainted [ 43.169283] ----------------------------- [ 43.169863] kernel/trace/trace_events_trigger.c:145 RCU-list traversed in non-reader section!! ... However, this file->triggers list is safe when it is accessed under event_mutex is held. To fix this warning, adds a lockdep_is_held check to the list_for_each_entry_rcu(). Link: https://lkml.kernel.org/r/166226474977.223837.1992182913048377113.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-06tracing: hold caller_addr to hardirq_{enable,disable}_ipYipeng Zou1-2/+2
Currently, The arguments passing to lockdep_hardirqs_{on,off} was fixed in CALLER_ADDR0. The function trace_hardirqs_on_caller should have been intended to use caller_addr to represent the address that caller wants to be traced. For example, lockdep log in riscv showing the last {enabled,disabled} at __trace_hardirqs_{on,off} all the time(if called by): [ 57.853175] hardirqs last enabled at (2519): __trace_hardirqs_on+0xc/0x14 [ 57.853848] hardirqs last disabled at (2520): __trace_hardirqs_off+0xc/0x14 After use trace_hardirqs_xx_caller, we can get more effective information: [ 53.781428] hardirqs last enabled at (2595): restore_all+0xe/0x66 [ 53.782185] hardirqs last disabled at (2596): ret_from_exception+0xa/0x10 Link: https://lkml.kernel.org/r/20220901104515.135162-2-zouyipeng@huawei.com Cc: stable@vger.kernel.org Fixes: c3bc8fd637a96 ("tracing: Centralize preemptirq tracepoints and unify their usage") Signed-off-by: Yipeng Zou <zouyipeng@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-06tracepoint: Allow trace events in modules with TAINT_TESTAlison Schofield1-2/+3
Commit 2852ca7fba9f ("panic: Taint kernel if tests are run") introduced a new taint type, TAINT_TEST, to signal that an in-kernel test module has been loaded. TAINT_TEST taint type defaults into a 'bad_taint' list for kernel tracing and blocks the creation of trace events. This causes a problem for CXL testing where loading the cxl_test module makes all CXL modules out-of-tree, blocking any trace events. Trace events are in development for CXL at the moment and this issue was found in test with v6.0-rc1. Link: https://lkml.kernel.org/r/20220829171048.263065-1-alison.schofield@intel.com Fixes: 2852ca7fba9f7 ("panic: Taint kernel if tests are run") Reported-by: Ira Weiny <ira.weiny@intel.com> Suggested-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-06rv/monitors: Make monitor's automata definition staticDaniel Bristot de Oliveira2-2/+2
Monitor's automata definition is only used locally, so make them static for all existing monitors. Link: https://lore.kernel.org/all/202208210332.gtHXje45-lkp@intel.com Link: https://lore.kernel.org/all/202208210358.6HH3OrVs-lkp@intel.com Link: https://lkml.kernel.org/r/a50e27c3738d6ef809f4201857229fed64799234.1661266564.git.bristot@kernel.org Fixes: ccc319dcb450 ("rv/monitor: Add the wwnr monitor") Fixes: 8812d21219b9 ("rv/monitor: Add the wip monitor skeleton created by dot2k") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-06perf/core: Fix reentry problem in perf_output_read_group()Yang Jihong1-0/+9
perf_output_read_group may respond to IPI request of other cores and invoke __perf_install_in_context function. As a result, hwc configuration is modified. causing inconsistency and unexpected consequences. Interrupts are not disabled when perf_output_read_group reads PMU counter. In this case, IPI request may be received from other cores. As a result, PMU configuration is modified and an error occurs when reading PMU counter: CPU0 CPU1 __se_sys_perf_event_open perf_install_in_context perf_output_read_group smp_call_function_single for_each_sibling_event(sub, leader) { generic_exec_single if ((sub != event) && remote_function (sub->state == PERF_EVENT_STATE_ACTIVE)) | <enter IPI handler: __perf_install_in_context> <----RAISE IPI-----+ __perf_install_in_context ctx_resched event_sched_out armpmu_del ... hwc->idx = -1; // event->hwc.idx is set to -1 ... <exit IPI> sub->pmu->read(sub); armpmu_read armv8pmu_read_counter armv8pmu_read_hw_counter int idx = event->hw.idx; // idx = -1 u64 val = armv8pmu_read_evcntr(idx); u32 counter = ARMV8_IDX_TO_COUNTER(idx); // invalid counter = 30 read_pmevcntrn(counter) // undefined instruction Signed-off-by: Yang Jihong <yangjihong1@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20220902082918.179248-1-yangjihong1@huawei.com
2022-09-05IB/core: Fix a nested dead lock as part of ODP flowYishai Hadas1-0/+1
Fix a nested dead lock as part of ODP flow by using mmput_async(). From the below call trace [1] can see that calling mmput() once we have the umem_odp->umem_mutex locked as required by ib_umem_odp_map_dma_and_lock() might trigger in the same task the exit_mmap()->__mmu_notifier_release()->mlx5_ib_invalidate_range() which may dead lock when trying to lock the same mutex. Moving to use mmput_async() will solve the problem as the above exit_mmap() flow will be called in other task and will be executed once the lock will be available. [1] [64843.077665] task:kworker/u133:2 state:D stack: 0 pid:80906 ppid: 2 flags:0x00004000 [64843.077672] Workqueue: mlx5_ib_page_fault mlx5_ib_eqe_pf_action [mlx5_ib] [64843.077719] Call Trace: [64843.077722] <TASK> [64843.077724] __schedule+0x23d/0x590 [64843.077729] schedule+0x4e/0xb0 [64843.077735] schedule_preempt_disabled+0xe/0x10 [64843.077740] __mutex_lock.constprop.0+0x263/0x490 [64843.077747] __mutex_lock_slowpath+0x13/0x20 [64843.077752] mutex_lock+0x34/0x40 [64843.077758] mlx5_ib_invalidate_range+0x48/0x270 [mlx5_ib] [64843.077808] __mmu_notifier_release+0x1a4/0x200 [64843.077816] exit_mmap+0x1bc/0x200 [64843.077822] ? walk_page_range+0x9c/0x120 [64843.077828] ? __cond_resched+0x1a/0x50 [64843.077833] ? mutex_lock+0x13/0x40 [64843.077839] ? uprobe_clear_state+0xac/0x120 [64843.077860] mmput+0x5f/0x140 [64843.077867] ib_umem_odp_map_dma_and_lock+0x21b/0x580 [ib_core] [64843.077931] pagefault_real_mr+0x9a/0x140 [mlx5_ib] [64843.077962] pagefault_mr+0xb4/0x550 [mlx5_ib] [64843.077992] pagefault_single_data_segment.constprop.0+0x2ac/0x560 [mlx5_ib] [64843.078022] mlx5_ib_eqe_pf_action+0x528/0x780 [mlx5_ib] [64843.078051] process_one_work+0x22b/0x3d0 [64843.078059] worker_thread+0x53/0x410 [64843.078065] ? process_one_work+0x3d0/0x3d0 [64843.078073] kthread+0x12a/0x150 [64843.078079] ? set_kthread_struct+0x50/0x50 [64843.078085] ret_from_fork+0x22/0x30 [64843.078093] </TASK> Fixes: 36f30e486dce ("IB/core: Improve ODP to use hmm_range_fault()") Reviewed-by: Maor Gottlieb <maorg@nvidia.com> Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Link: https://lore.kernel.org/r/74d93541ea533ef7daec6f126deb1072500aeb16.1661251841.git.leonro@nvidia.com Signed-off-by: Leon Romanovsky <leon@kernel.org>
2022-09-05sched/debug: fix dentry leak in update_sched_domain_debugfsGreg Kroah-Hartman1-1/+1
Kuyo reports that the pattern of using debugfs_remove(debugfs_lookup()) leaks a dentry and with a hotplug stress test, the machine eventually runs out of memory. Fix this up by using the newly created debugfs_lookup_and_remove() call instead which properly handles the dentry reference counting logic. Cc: Major Chen <major.chen@samsung.com> Cc: stable <stable@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ben Segall <bsegall@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Reported-by: Kuyo Chang <kuyo.chang@mediatek.com> Tested-by: Kuyo Chang <kuyo.chang@mediatek.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220902123107.109274-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01Merge branches 'doc.2022.08.31b', 'fixes.2022.08.31b', 'kvfree.2022.08.31b', ↵Paul E. McKenney11-153/+628
'nocb.2022.09.01a', 'poll.2022.08.31b', 'poll-srcu.2022.08.31b' and 'tasks.2022.08.31b' into HEAD doc.2022.08.31b: Documentation updates fixes.2022.08.31b: Miscellaneous fixes kvfree.2022.08.31b: kvfree_rcu() updates nocb.2022.09.01a: NOCB CPU updates poll.2022.08.31b: Full-oldstate RCU polling grace-period API poll-srcu.2022.08.31b: Polled SRCU grace-period updates tasks.2022.08.31b: Tasks RCU updates
2022-09-01rcutorture: Use the barrier operation specified by cur_opsZqiang1-2/+2
The rcutorture_oom_notify() function unconditionally invokes rcu_barrier(), which is OK when the rcutorture.torture_type value is "rcu", but unhelpful otherwise. The purpose of these barrier calls is to wait for all outstanding callback-flooding callbacks to be invoked before cleaning up their data. Using the wrong barrier function therefore risks arbitrary memory corruption. Thus, this commit changes these rcu_barrier() calls into cur_ops->cb_barrier() to make things work when torturing non-vanilla flavors of RCU. Signed-off-by: Zqiang <qiang1.zhang@intel.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-09-01Merge tag 'net-6.0-rc4' of ↵Linus Torvalds4-9/+12
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from bluetooth, bpf and wireless. Current release - regressions: - bpf: - fix wrong last sg check in sk_msg_recvmsg() - fix kernel BUG in purge_effective_progs() - mac80211: - fix possible leak in ieee80211_tx_control_port() - potential NULL dereference in ieee80211_tx_control_port() Current release - new code bugs: - nfp: fix the access to management firmware hanging Previous releases - regressions: - ip: fix triggering of 'icmp redirect' - sched: tbf: don't call qdisc_put() while holding tree lock - bpf: fix corrupted packets for XDP_SHARED_UMEM - bluetooth: hci_sync: fix suspend performance regression - micrel: fix probe failure Previous releases - always broken: - tcp: make global challenge ack rate limitation per net-ns and default disabled - tg3: fix potential hang-up on system reboot - mac802154: fix reception for no-daddr packets Misc: - r8152: add PID for the lenovo onelink+ dock" * tag 'net-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (56 commits) net/smc: Remove redundant refcount increase Revert "sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb" tcp: make global challenge ack rate limitation per net-ns and default disabled tcp: annotate data-race around challenge_timestamp net: dsa: hellcreek: Print warning only once ip: fix triggering of 'icmp redirect' sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb selftests: net: sort .gitignore file Documentation: networking: correct possessive "its" kcm: fix strp_init() order and cleanup mlxbf_gige: compute MDIO period based on i1clk ethernet: rocker: fix sleep in atomic context bug in neigh_timer_handler net: lan966x: improve error handle in lan966x_fdma_rx_get_frame() nfp: fix the access to management firmware hanging net: phy: micrel: Make the GPIO to be non-exclusive net: virtio_net: fix notification coalescing comments net/sched: fix netdevice reference leaks in attach_default_qdiscs() net: sched: tbf: don't call qdisc_put() while holding tree lock net: Use u64_stats_fetch_begin_irq() for stats fetch. net: dsa: xrs700x: Use irqsave variant for u64 stats update ...
2022-08-31rcu-tasks: Make RCU Tasks Trace check for userspace executionZqiang2-6/+2
Userspace execution is a valid quiescent state for RCU Tasks Trace, but the scheduling-clock interrupt does not currently report such quiescent states. Of course, the scheduling-clock interrupt is not strictly speaking userspace execution. However, the only way that this code is not in a quiescent state is if something invoked rcu_read_lock_trace(), and that would be reflected in the ->trc_reader_nesting field in the task_struct structure. Furthermore, this field is checked by rcu_tasks_trace_qs(), which is invoked by rcu_tasks_qs() which is in turn invoked by rcu_note_voluntary_context_switch() in kernels building at least one of the RCU Tasks flavors. It is therefore safe to invoke rcu_tasks_trace_qs() from the rcu_sched_clock_irq(). But rcu_tasks_qs() also invokes rcu_tasks_classic_qs() for RCU Tasks, which lacks the read-side markers provided by RCU Tasks Trace. This raises the possibility that an RCU Tasks grace period could start after the interrupt from userspace execution, but before the call to rcu_sched_clock_irq(). However, it turns out that this is safe because the RCU Tasks grace period waits for an RCU grace period, which will wait for the entire scheduling-clock interrupt handler, including any RCU Tasks read-side critical section that this handler might contain. This commit therefore updates the rcu_sched_clock_irq() function's check for usermode execution and its call to rcu_tasks_classic_qs() to instead check for both usermode execution and interrupt from idle, and to instead call rcu_note_voluntary_context_switch(). This consolidates code and provides more faster RCU Tasks Trace reporting of quiescent states in kernels that do scheduling-clock interrupts for userspace execution. [ paulmck: Consolidate checks into rcu_sched_clock_irq(). ] Signed-off-by: Zqiang <qiang1.zhang@intel.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu-tasks: Ensure RCU Tasks Trace loops have quiescent statesPaul E. McKenney1-0/+3
The RCU Tasks Trace grace-period kthread loops across all CPUs, and there can be quite a few CPUs, with some commercially available systems sporting well over a thousand of them. Some of these loops can feature IPIs, which can take some time. This commit therefore places a call to cond_resched_tasks_rcu_qs() in each such loop. Link: https://docs.google.com/document/d/1V0YnG1HTWMt9WHJjroiJL9lf-hMrud4v8Fn3fhyY0cI/edit?usp=sharing Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu-tasks: Convert RCU_LOCKDEP_WARN() to WARN_ONCE()Zqiang1-1/+1
Kernels built with CONFIG_PROVE_RCU=y and CONFIG_DEBUG_LOCK_ALLOC=y attempt to emit a warning when the synchronize_rcu_tasks_generic() function is called during early boot while the rcu_scheduler_active variable is RCU_SCHEDULER_INACTIVE. However the warnings is not actually be printed because the debug_lockdep_rcu_enabled() returns false, exactly because the rcu_scheduler_active variable is still equal to RCU_SCHEDULER_INACTIVE. This commit therefore replaces RCU_LOCKDEP_WARN() with WARN_ONCE() to force these warnings to actually be printed. Signed-off-by: Zqiang <qiang1.zhang@intel.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31srcu: Make Tiny SRCU use full-sized grace-period countersPaul E. McKenney1-7/+7
This commit makes Tiny SRCU use full-sized grace-period counters to further avoid counter-wrap issues when using polled grace-period APIs. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31srcu: Make Tiny SRCU poll_state_synchronize_srcu() more precisePaul E. McKenney1-2/+2
This commit applies the more-precise grace-period-state check used by rcu_seq_done_exact() to poll_state_synchronize_srcu(). This is important because Tiny SRCU uses a 16-bit counter, which can wrap quite quickly. If counter wrap continues to be a problem, then expanding ->srcu_idx and ->srcu_idx_max to 32 bits might be warranted. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcutorture: Make "srcud" option also test polled grace-period APIPaul E. McKenney1-0/+3
This commit brings the "srcud" (dynamically allocated) SRCU test in line with the "srcu" (statically allocated) test, so that both test the full SRCU polled grace-period API. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcutorture: Limit read-side polling-API testingPaul E. McKenney1-18/+23
RCU's polled grace-period API is reasonably lightweight, but still contains heavyweight memory barriers. This commit therefore limits testing of this API from rcutorture's readers in order to avoid the false negatives that these heavyweight operations could provoke. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcutorture: Expand rcu_torture_write_types() first "if" statementPaul E. McKenney1-6/+23
This commit expands the rcu_torture_write_types() function's first "if" condition and body, placing one element per line, in order to make the compiler's error messages more helpful. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcutorture: Use 1-suffixed variable in rcu_torture_write_types() checkPaul E. McKenney1-1/+1
This commit changes the use of gp_poll_exp to gp_poll_exp1 in the first check in rcu_torture_write_types(). No functional effect, but consistency is a good thing. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Make synchronize_rcu() fastpath update only boot-CPU countersPaul E. McKenney1-2/+16
Large systems can have hundreds of rcu_node structures, and updating counters in each of them might slow down booting. This commit therefore updates only the counters in those rcu_node structures corresponding to the boot CPU, up to and including the root rcu_node structure. The counters for the remaining rcu_node structures are updated by the rcu_scheduler_starting() function, which executes just before the first non-boot kthread is spawned. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcutorture: Adjust rcu_poll_need_2gp() for rcu_gp_oldstate field removalPaul E. McKenney1-1/+1
Now that rcu_gp_oldstate can accurately track both normal and expedited grace periods regardless of system state, rcutorture's rcu_poll_need_2gp() function need only call for a second grace period for the old single-unsigned-long grace-period polling APIs This commit therefore adjusts rcu_poll_need_2gp() accordingly. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Remove ->rgos_polled field from rcu_gp_oldstate structurePaul E. McKenney1-5/+1
Because both normal and expedited grace periods increment their respective counters on their pre-scheduler early boot fastpaths, the rcu_gp_oldstate structure no longer needs its ->rgos_polled field. This commit therefore removes this field, shrinking this structure so that it is the same size as an rcu_head structure. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Make synchronize_rcu_expedited() fast path update .expedited_sequencePaul E. McKenney1-0/+6
This commit causes the early boot single-CPU synchronize_rcu_expedited() fastpath to update the rcu_state structure's ->expedited_sequence counter. This will allow the full-state polled grace-period APIs to detect all expedited grace periods without the need to track the special combined polling-only counter, which is another step towards removing the ->rgos_polled field from the rcu_gp_oldstate, thereby reducing its size by one third. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Remove expedited grace-period fast-path forward-progress helperPaul E. McKenney1-2/+0
Now that the expedited grace-period fast path can only happen during the pre-scheduler portion of early boot, this fast path can no longer block run-time RCU Trace grace periods. This commit therefore removes the conditional cond_resched() invocation. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Make synchronize_rcu() fast path update ->gp_seq countersPaul E. McKenney1-13/+26
This commit causes the early boot single-CPU synchronize_rcu() fastpath to update the rcu_state and rcu_node structures' ->gp_seq and ->gp_seq_needed counters. This will allow the full-state polled grace-period APIs to detect all normal grace periods without the need to track the special combined polling-only counter, which is a step towards removing the ->rgos_polled field from the rcu_gp_oldstate, thereby reducing its size by one third. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu-tasks: Remove grace-period fast-path rcu-tasks helperPaul E. McKenney1-2/+0
Now that the grace-period fast path can only happen during the pre-scheduler portion of early boot, this fast path can no longer block run-time RCU Tasks and RCU Tasks Trace grace periods. This commit therefore removes the conditional cond_resched_tasks_rcu_qs() invocation. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Set rcu_data structures' initial ->gpwrap value to truePaul E. McKenney1-0/+1
It would be good do reduce the size of the rcu_gp_oldstate structure from three unsigned long instances to two, but this requires that the boot-time optimized grace periods update the various ->gp_seq fields. Updating these fields in the rcu_state structure and in all of the rcu_node structures is at least semi-reasonable, but updating them in all of the rcu_data structures is a bridge too far. This means that if there are too many early boot-time grace periods, the ->gp_seq field in the rcu_data structure cannot be trusted. This commit therefore sets each rcu_data structure's ->gpwrap field to provide the necessary impetus for a suitable level of distrust. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Disable run-time single-CPU grace-period optimizationPaul E. McKenney1-31/+9
The run-time single-CPU grace-period optimization applies only to kernels built with CONFIG_SMP=y && CONFIG_PREEMPTION=y that are running on a single-CPU system. But a kernel intended for a single-CPU system should instead be built with CONFIG_SMP=n, and in any case, single-CPU systems running Linux no longer appear to be the common case. Plus this optimization results in the rcu_gp_oldstate structure being half again larger than it needs to be. This commit therefore disables the run-time single-CPU grace-period optimization, so that this optimization applies only during the pre-scheduler portion of the boot sequence. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Add full-sized polling for cond_sync_exp_full()Paul E. McKenney2-22/+77
The cond_synchronize_rcu_expedited() API compresses the combined expedited and normal grace-period states into a single unsigned long, which conserves storage, but can miss grace periods in certain cases involving overlapping normal and expedited grace periods. Missing the occasional grace period is usually not a problem, but there are use cases that care about each and every grace period. This commit therefore adds yet another member of the full-state RCU grace-period polling API, which is the cond_synchronize_rcu_exp_full() function. This uses up to three times the storage (rcu_gp_oldstate structure instead of unsigned long), but is guaranteed not to miss grace periods. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Add full-sized polling for cond_sync_full()Paul E. McKenney2-21/+74
The cond_synchronize_rcu() API compresses the combined expedited and normal grace-period states into a single unsigned long, which conserves storage, but can miss grace periods in certain cases involving overlapping normal and expedited grace periods. Missing the occasional grace period is usually not a problem, but there are use cases that care about each and every grace period. This commit therefore adds yet another member of the full-state RCU grace-period polling API, which is the cond_synchronize_rcu_full() function. This uses up to three times the storage (rcu_gp_oldstate structure instead of unsigned long), but is guaranteed not to miss grace periods. [ paulmck: Apply feedback from kernel test robot and Julia Lawall. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-08-31rcu: Remove blank line from poll_state_synchronize_rcu() docbook headerPaul E. McKenney1-3/+2
This commit removes the blank line preceding the oldstate parameter to the docbook header for the poll_state_synchronize_rcu() function and marks uses of this parameter later in that header. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>