June 2023 - Linux-kselftest-mirror

[PATCH 0/2] proc: proc_setattr for /proc/$PID/net

by Thomas Weißschuh

/proc/$PID/net currently allows the setting of file attributes, in contrast to other /proc/$PID/ files and directories. This would break the nolibc testsuite so the first patch in the series removes the offending testcase. The "fix" for nolibc-test is intentionally kept trivial as the series will most likely go through the filesystem tree and if conflicts arise, it is obvious on how to resolve them. Technically this can lead to breakage of nolibc-test if an old nolibc-test is used with a newer kernel containing the fix. Note: Except for /proc itself this is the only "struct inode_operations" in fs/proc/ that is missing an implementation of setattr(). Signed-off-by: Thomas Weißschuh <linux(a)weissschuh.net> --- Thomas Weißschuh (2): selftests/nolibc: drop test chmod_net proc: use generic setattr() for /proc/$PID/net fs/proc/proc_net.c | 1 + tools/testing/selftests/nolibc/nolibc-test.c | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) --- base-commit: a92b7d26c743b9dc06d520f863d624e94978a1d9 change-id: 20230624-proc-net-setattr-8f0a6b8eb2f5 Best regards, -- Thomas Weißschuh <linux(a)weissschuh.net>

10 months, 3 weeks

5
15
0 0

[PATCH v4 0/9] cgroup/cpuset: Support remote partitions

by Waiman Long

v4: - [v3] https://lore.kernel.org/lkml/20230627005529.1564984-1-longman@redhat.com/ - Fix compilation problem reported by kernel test robot. v3: - [v2] https://lore.kernel.org/lkml/20230531163405.2200292-1-longman@redhat.com/ - Change the new control file from root-only "cpuset.cpus.reserve" to non-root "cpuset.cpus.exclusive" which lists the set of exclusive CPUs distributed down the hierarchy. - Add a patch to restrict boot-time isolated CPUs to isolated partitions only. - Update the test_cpuset_prs.sh test script and documentation accordingly. This patch series introduces a new cpuset control file "cpuset.cpus.exclusive" which must be a subset of "cpuset.cpus" and the parent's "cpuset.cpus.exclusive". This control file lists the exclusive CPUs to be distributed down the hierarchy. Any one of the exclusive CPUs can only be distributed to at most one child cpuset. Unlike "cpuset.cpus", invalid input to "cpuset.cpus.exclusive" will be rejected with an error. This new control file has no effect on the behavior of the cpuset until it turns into a partition root. At that point, its effective CPUs will be set to its exclusive CPUs unless some of them are offline. This patch series also introduces a new category of cpuset partition called remote partitions. The existing partition category where the partition roots have to be clustered around the root cgroup in a hierarchical way is now referred to as local partitions. A remote partition can be formed far from the root cgroup with no partition root parent. While local partitions can be created without touching "cpuset.cpus.exclusive" as it can be set automatically if a cpuset becomes a local partition root. Properly set "cpuset.cpus.exclusive" values down the hierarchy are required to create a remote partition. Both scheduling and isolated partitions can be formed in a remote partition. A local partition can be created under a remote partition. A remote partition, however, cannot be formed under a local partition for now. Modern container orchestration tools like Kubernetes use the cgroup hierarchy to manage different containers. And it is relying on other middleware like systemd to help managing it. If a container needs to use isolated CPUs, it is hard to get those with the local partitions as it will require the administrative parent cgroup to be a partition root too which tool like systemd may not be ready to manage. With this patch series, we allow the creation of remote partition far from the root. The container management tool can manage the "cpuset.cpus.exclusive" file without impacting the other cpuset files that are managed by other middlewares. Of course, invalid "cpuset.cpus.exclusive" values will be rejected and changes to "cpuset.cpus" can affect the value of "cpuset.cpus.exclusive" due to the requirement that it has to be a subset of the former control file. Waiman Long (9): cgroup/cpuset: Inherit parent's load balance state in v2 cgroup/cpuset: Extract out CS_CPU_EXCLUSIVE & CS_SCHED_LOAD_BALANCE handling cgroup/cpuset: Improve temporary cpumasks handling cgroup/cpuset: Allow suppression of sched domain rebuild in update_cpumasks_hier() cgroup/cpuset: Add cpuset.cpus.exclusive for v2 cgroup/cpuset: Introduce remote partition cgroup/cpuset: Check partition conflict with housekeeping setup cgroup/cpuset: Documentation update for partition cgroup/cpuset: Extend test_cpuset_prs.sh to test remote partition Documentation/admin-guide/cgroup-v2.rst | 100 +- kernel/cgroup/cpuset.c | 1347 ++++++++++++----- .../selftests/cgroup/test_cpuset_prs.sh | 398 +++-- 3 files changed, 1291 insertions(+), 554 deletions(-) -- 2.31.1

10 months, 3 weeks

2
21
0 0

[PATCH bpf-next v4 0/7] Add SO_REUSEPORT support for TC bpf_sk_assign

by Lorenz Bauer

We want to replace iptables TPROXY with a BPF program at TC ingress. To make this work in all cases we need to assign a SO_REUSEPORT socket to an skb, which is currently prohibited. This series adds support for such sockets to bpf_sk_assing. I did some refactoring to cut down on the amount of duplicate code. The key to this is to use INDIRECT_CALL in the reuseport helpers. To show that this approach is not just beneficial to TC sk_assign I removed duplicate code for bpf_sk_lookup as well. Joint work with Daniel Borkmann. Signed-off-by: Lorenz Bauer <lmb(a)isovalent.com> --- Changes in v4: - WARN_ON_ONCE if reuseport socket is refcounted (Kuniyuki) - Use inet[6]_ehashfn_t to shorten function declarations (Kuniyuki) - Shuffle documentation patch around (Kuniyuki) - Update commit message to explain why IPv6 needs EXPORT_SYMBOL - Link to v3: https://lore.kernel.org/r/20230613-so-reuseport-v3-0-907b4cbb7b99@isovalent… Changes in v3: - Fix warning re udp_ehashfn and udp6_ehashfn (Simon) - Return higher scoring connected UDP reuseport sockets (Kuniyuki) - Fix ipv6 module builds - Link to v2: https://lore.kernel.org/r/20230613-so-reuseport-v2-0-b7c69a342613@isovalent… Changes in v2: - Correct commit abbrev length (Kuniyuki) - Reduce duplication (Kuniyuki) - Add checks on sk_state (Martin) - Split exporting inet[6]_lookup_reuseport into separate patch (Eric) --- Daniel Borkmann (1): selftests/bpf: Test that SO_REUSEPORT can be used with sk_assign helper Lorenz Bauer (6): udp: re-score reuseport groups when connected sockets are present net: export inet_lookup_reuseport and inet6_lookup_reuseport net: remove duplicate reuseport_lookup functions net: document inet[6]_lookup_reuseport sk_state requirements net: remove duplicate sk_lookup helpers bpf, net: Support SO_REUSEPORT sockets with bpf_sk_assign include/net/inet6_hashtables.h | 81 ++++++++- include/net/inet_hashtables.h | 74 +++++++- include/net/sock.h | 7 +- include/uapi/linux/bpf.h | 3 - net/core/filter.c | 2 - net/ipv4/inet_hashtables.c | 67 ++++--- net/ipv4/udp.c | 88 ++++----- net/ipv6/inet6_hashtables.c | 70 +++++--- net/ipv6/udp.c | 98 ++++------ tools/include/uapi/linux/bpf.h | 3 - tools/testing/selftests/bpf/network_helpers.c | 3 + .../selftests/bpf/prog_tests/assign_reuse.c | 197 +++++++++++++++++++++ .../selftests/bpf/progs/test_assign_reuse.c | 142 +++++++++++++++ 13 files changed, 656 insertions(+), 179 deletions(-) --- base-commit: 970308a7b544fa1c7ee98a2721faba3765be8dd8 change-id: 20230613-so-reuseport-e92c526173ee Best regards, -- Lorenz Bauer <lmb(a)isovalent.com>

10 months, 3 weeks

3
19
0 0

[PATCH v7 00/19] Add iommufd physical device operations for replace and alloc hwpt

by Jason Gunthorpe

This is the basic functionality for iommufd to support iommufd_device_replace() and IOMMU_HWPT_ALLOC for physical devices. iommufd_device_replace() allows changing the HWPT associated with the device to a new IOAS or HWPT. Replace does this in way that failure leaves things unchanged, and utilizes the iommu iommu_group_replace_domain() API to allow the iommu driver to perform an optional non-disruptive change. IOMMU_HWPT_ALLOC allows HWPTs to be explicitly allocated by the user and used by attach or replace. At this point it isn't very useful since the HWPT is the same as the automatically managed HWPT from the IOAS. However a following series will allow userspace to customize the created HWPT. The implementation is complicated because we have to introduce some per-iommu_group memory in iommufd and redo how we think about multi-device groups to be more explicit. This solves all the locking problems in the prior attempts. This series is infrastructure work for the following series which: - Add replace for attach - Expose replace through VFIO APIs - Implement driver parameters for HWPT creation (nesting) Once review of this is complete I will keep it on a side branch and accumulate the following series when they are ready so we can have a stable base and make more incremental progress. When we have all the parts together to get a full implementation it can go to Linus. This is on github: https://github.com/jgunthorpe/linux/commits/iommufd_hwpt v7: - Rebase to v6.4-rc2, update to new signature of iommufd_get_ioas() v6: https://lore.kernel.org/r/0-v6-fdb604df649a+369-iommufd_alloc_jgg@nvidia.com - Go back to the v4 locking arragnment with now both the attach/detach igroup->locks inside the functions, Kevin says he needs this for a followup series. This still fixes the syzkaller bug - Fix two more error unwind locking bugs where iommufd_object_abort_and_destroy(hwpt) would deadlock or be mislocked. Make sure fail_nth will catch these mistakes - Add a patch allowing objects to have different abort than destroy function, it allows hwpt abort to require the caller to continue to hold the lock and enforces this with lockdep. v5: https://lore.kernel.org/r/0-v5-6716da355392+c5-iommufd_alloc_jgg@nvidia.com - Go back to the v3 version of the code, keep the comment changes from v4. Syzkaller says the group lock change in v4 didn't work. - Adjust the fail_nth test to cover the path syzkaller found. We need to have an ioas with a mapped page installed to inject a failure during domain attachment. v4: https://lore.kernel.org/r/0-v4-9cd79ad52ee8+13f5-iommufd_alloc_jgg@nvidia.c… - Refine comments and commit messages - Move the group lock into iommufd_hw_pagetable_attach() - Fix error unwind in iommufd_device_do_replace() v3: https://lore.kernel.org/r/0-v3-61d41fd9e13e+1f5-iommufd_alloc_jgg@nvidia.com - Refine comments and commit messages - Adjust the flow in iommufd_device_auto_get_domain() so pt_id is only set on success - Reject replace on non-attached devices - Add missing __reserved check for IOMMU_HWPT_ALLOC v2: https://lore.kernel.org/r/0-v2-51b9896e7862+8a8c-iommufd_alloc_jgg@nvidia.c… - Use WARN_ON for the igroup->group test and move that logic to a function iommufd_group_try_get() - Change igroup->devices to igroup->device list Replace will need to iterate over all attached idevs - Rename to iommufd_group_setup_msi() - New patch to export iommu_get_resv_regions() - New patch to use per-device reserved regions instead of per-group regions - Split out the reorganizing of iommufd_device_change_pt() from the replace patch - Replace uses the per-dev reserved regions - Use stdev_id in a few more places in the selftest - Fix error handling in IOMMU_HWPT_ALLOC - Clarify comments - Rebase on v6.3-rc1 v1: https://lore.kernel.org/all/0-v1-7612f88c19f5+2f21-iommufd_alloc_jgg@nvidia… Jason Gunthorpe (17): iommufd: Move isolated msi enforcement to iommufd_device_bind() iommufd: Add iommufd_group iommufd: Replace the hwpt->devices list with iommufd_group iommu: Export iommu_get_resv_regions() iommufd: Keep track of each device's reserved regions instead of groups iommufd: Use the iommufd_group to avoid duplicate MSI setup iommufd: Make sw_msi_start a group global iommufd: Move putting a hwpt to a helper function iommufd: Add enforced_cache_coherency to iommufd_hw_pagetable_alloc() iommufd: Allow a hwpt to be aborted after allocation iommufd: Fix locking around hwpt allocation iommufd: Reorganize iommufd_device_attach into iommufd_device_change_pt iommufd: Add iommufd_device_replace() iommufd: Make destroy_rwsem use a lock class per object type iommufd: Add IOMMU_HWPT_ALLOC iommufd/selftest: Return the real idev id from selftest mock_domain iommufd/selftest: Add a selftest for IOMMU_HWPT_ALLOC Nicolin Chen (2): iommu: Introduce a new iommu_group_replace_domain() API iommufd/selftest: Test iommufd_device_replace() drivers/iommu/iommu-priv.h | 10 + drivers/iommu/iommu.c | 41 +- drivers/iommu/iommufd/device.c | 553 +++++++++++++----- drivers/iommu/iommufd/hw_pagetable.c | 112 +++- drivers/iommu/iommufd/io_pagetable.c | 32 +- drivers/iommu/iommufd/iommufd_private.h | 52 +- drivers/iommu/iommufd/iommufd_test.h | 6 + drivers/iommu/iommufd/main.c | 24 +- drivers/iommu/iommufd/selftest.c | 40 ++ include/linux/iommufd.h | 1 + include/uapi/linux/iommufd.h | 26 + tools/testing/selftests/iommu/iommufd.c | 67 ++- .../selftests/iommu/iommufd_fail_nth.c | 67 ++- tools/testing/selftests/iommu/iommufd_utils.h | 63 +- 14 files changed, 868 insertions(+), 226 deletions(-) create mode 100644 drivers/iommu/iommu-priv.h base-commit: f1fcbaa18b28dec10281551dfe6ed3a3ed80e3d6 -- 2.40.1

10 months, 4 weeks

5
36
0 0

ww_mutex.sh hangs since v5.16-rc1

by Li Zhijian

Hi Folks LKP/0Day found that ww_mutex.sh cannot complete since v5.16-rc1, but I'm pretty sorry that we failed to bisect the FBC, instead, the bisection pointed to a/below merge commit(91e1c99e17) finally. Due to this hang, other tests in the same group are also blocked in 0Day, we hope we can fix this hang ASAP. So if you have any idea about this, or need more debug information, feel free to let me know :) BTW, ww_mutex.sh was failed in v5.15 without hang, and looks it cannot reproduce on a vm. Our box: root@lkp-knm01 ~# lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian Address sizes: 46 bits physical, 48 bits virtual CPU(s): 288 On-line CPU(s) list: 0-287 Thread(s) per core: 4 Core(s) per socket: 72 Socket(s): 1 NUMA node(s): 2 Vendor ID: GenuineIntel CPU family: 6 Model: 133 Model name: Intel(R) Xeon Phi(TM) CPU 7295 @ 1.50GHz Stepping: 0 CPU MHz: 1385.255 CPU max MHz: 1600.0000 CPU min MHz: 1000.0000 BogoMIPS: 2992.76 Virtualization: VT-x L1d cache: 32K L1i cache: 32K L2 cache: 1024K NUMA node0 CPU(s): 0-287 NUMA node1 CPU(s): Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 fma cx16 xtpr pdcm sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch ring3mwait cpuid_fault epb pti tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms avx512f rdseed adx avx512pf avx512er avx512cd xsaveopt dtherm ida arat pln pts avx512_vpopcntdq avx512_4vnniw avx512_4fmaps Below the call stack in v5.16-rc2 [ 1000.374954][ T2713] make: Leaving directory '/usr/src/perf_selftests-x86_64-rhel-8.3-kselftests-136057256686de39cc3a07c2e39ef6bc43003ff6/tools/testing/selftests/locking' [ 1000.375030][ T2713] [ 1000.428791][ T2713] 2021-11-22 22:21:27 make run_tests -C locking [ 1000.428864][ T2713] [ 1000.491043][ T2713] make: Entering directory '/usr/src/perf_selftests-x86_64-rhel-8.3-kselftests-136057256686de39cc3a07c2e39ef6bc43003ff6/tools/testing/selftests/locking' [ 1000.491121][ T2713] [ 1000.540807][ T2713] TAP version 13 [ 1000.540882][ T2713] [ 1000.576050][ T2713] 1..1 [ 1000.576282][ T2713] [ 1000.612980][ T2713] # selftests: locking: ww_mutex.sh [ 1000.613288][ T2713] [ 1495.201324][ T1577] INFO: task kworker/u576:16:1470 blocked for more than 491 seconds. [ 1495.220059][ T1577] Tainted: G B 5.16.0-rc2 #1 [ 1495.240902][ T1577] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1495.265617][ T1577] task:kworker/u576:16 state:D stack: 0 pid: 1470 ppid: 2 flags:0x00004000 [ 1495.289054][ T1577] Workqueue: test-ww_mutex test_cycle_work [test_ww_mutex] [ 1495.310936][ T1577] Call Trace: [ 1495.327809][ T1577] <TASK> [ 1495.344735][ T1577] __schedule+0xdb0/0x25c0 [ 1495.362764][ T1577] ? io_schedule_timeout+0x180/0x180 [ 1495.382013][ T1577] ? lock_downgrade+0x680/0x680 [ 1495.400894][ T1577] ? do_raw_spin_lock+0x125/0x2c0 [ 1495.418866][ T1577] schedule+0xe4/0x280 [ 1495.435597][ T1577] schedule_preempt_disabled+0x18/0x40 [ 1495.454588][ T1577] __ww_mutex_lock+0x1248/0x34c0 [ 1495.476189][ T1577] ? test_cycle_work+0x1bb/0x500 [test_ww_mutex] [ 1495.497763][ T1577] ? mutex_lock_interruptible_nested+0x40/0x40 [ 1495.518959][ T1577] ? lock_downgrade+0x680/0x680 [ 1495.536861][ T1577] ? wait_for_completion_interruptible+0x340/0x340 [ 1495.556253][ T1577] ? ww_mutex_lock+0x3e/0x380 [ 1495.574003][ T1577] ww_mutex_lock+0x3e/0x380 [ 1495.591958][ T1577] test_cycle_work+0x1bb/0x500 [test_ww_mutex] [ 1495.612260][ T1577] ? stress_reorder_work+0xa00/0xa00 [test_ww_mutex] [ 1495.632857][ T1577] ? 0xffffffff81000000 [ 1495.649027][ T1577] ? rcu_read_lock_sched_held+0x5f/0x100 [ 1495.668211][ T1577] ? rcu_read_lock_bh_held+0xc0/0xc0 [ 1495.687010][ T1577] process_one_work+0x817/0x13c0 [ 1495.704991][ T1577] ? rcu_read_unlock+0x40/0x40 [ 1495.723024][ T1577] ? pwq_dec_nr_in_flight+0x280/0x280 [ 1495.740211][ T1577] ? rwlock_bug+0xc0/0xc0 [ 1495.758038][ T1577] worker_thread+0x8b/0xd80 [ 1495.775008][ T1577] ? process_one_work+0x13c0/0x13c0 [ 1495.793017][ T1577] kthread+0x3b9/0x4c0 [ 1495.810782][ T1577] ? set_kthread_struct+0x100/0x100 [ 1495.829988][ T1577] ret_from_fork+0x22/0x30 [ 1495.845811][ T1577] </TASK> [ 1495.859087][ T1577] INFO: task kworker/u576:36:1490 blocked for more than 492 seconds. [ 1495.879048][ T1577] Tainted: G B 5.16.0-rc2 #1 [ 1495.897879][ T1577] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1495.919582][ T1577] task:kworker/u576:36 state:D stack: 0 pid: 1490 ppid: 2 flags:0x00004000 [ 1495.941865][ T1577] Workqueue: test-ww_mutex test_cycle_work [test_ww_mutex] [ 1495.959889][ T1577] Call Trace: [ 1495.974816][ T1577] <TASK> [ 1495.988759][ T1577] __schedule+0xdb0/0x25c0 [ 1495.988759][ T1577] __schedule+0xdb0/0x25c0 [ 1496.003849][ T1577] ? io_schedule_timeout+0x180/0x180 [ 1496.020839][ T1577] ? lock_downgrade+0x680/0x680 [ 1496.036854][ T1577] ? do_raw_spin_lock+0x125/0x2c0 [ 1496.051976][ T1577] schedule+0xe4/0x280 [ 1496.067780][ T1577] schedule_preempt_disabled+0x18/0x40 [ 1496.085004][ T1577] __ww_mutex_lock+0x1248/0x34c0 [ 1496.101895][ T1577] ? test_cycle_work+0x1bb/0x500 [test_ww_mutex] [ 1496.119889][ T1577] ? mutex_lock_interruptible_nested+0x40/0x40 [ 1496.137873][ T1577] ? lock_downgrade+0x680/0x680 [ 1496.152657][ T1577] ? wait_for_completion_interruptible+0x340/0x340 [ 1496.168773][ T1577] ? ww_mutex_lock+0x3e/0x380 [ 1496.184862][ T1577] ww_mutex_lock+0x3e/0x380 [ 1496.199979][ T1577] test_cycle_work+0x1bb/0x500 [test_ww_mutex] [ 1496.216277][ T1577] ? stress_reorder_work+0xa00/0xa00 [test_ww_mutex] [ 1496.234904][ T1577] ? 0xffffffff81000000 [ 1496.249856][ T1577] ? rcu_read_lock_sched_held+0x5f/0x100 [ 1496.265951][ T1577] ? rcu_read_lock_bh_held+0xc0/0xc0 [ 1496.282815][ T1577] process_one_work+0x817/0x13c0 [ 1496.299791][ T1577] ? rcu_read_unlock+0x40/0x40 [ 1496.314754][ T1577] ? pwq_dec_nr_in_flight+0x280/0x280 [ 1496.331779][ T1577] ? rwlock_bug+0xc0/0xc0 [ 1496.348007][ T1577] worker_thread+0x8b/0xd80 [ 1496.362905][ T1577] ? process_one_work+0x13c0/0x13c0 [ 1496.378975][ T1577] kthread+0x3b9/0x4c0 [ 1496.393866][ T1577] ? set_kthread_struct+0x100/0x100 [ 1496.408827][ T1577] ret_from_fork+0x22/0x30 [ 1496.423901][ T1577] </TASK> [ 1496.437994][ T1577] INFO: task kworker/u576:0:15113 blocked for more than 492 seconds. [ 1496.455862][ T1577] Tainted: G B 5.16.0-rc2 #1 [ 1496.473759][ T1577] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1496.494808][ T1577] task:kworker/u576:0 state:D stack: 0 pid:15113 ppid: 2 flags:0x00004000 [ 1496.517000][ T1577] Workqueue: test-ww_mutex test_cycle_work [test_ww_mutex] [ 1496.537035][ T1577] Call Trace: [ 1496.551187][ T1577] <TASK> [ 1496.566405][ T1577] __schedule+0xdb0/0x25c0 [ 1496.582012][ T1577] ? io_schedule_timeout+0x180/0x180 [ 1496.598049][ T1577] ? lock_downgrade+0x680/0x680 [ 1496.615360][ T1577] ? do_raw_spin_lock+0x125/0x2c0 [ 1496.631835][ T1577] schedule+0xe4/0x280 [ 1496.645972][ T1577] schedule_preempt_disabled+0x18/0x40 [ 1496.663774][ T1577] __ww_mutex_lock+0x1248/0x34c0 [ 1496.681795][ T1577] ? test_cycle_work+0x1bb/0x500 [test_ww_mutex] [ 1496.698731][ T1577] ? mutex_lock_interruptible_nested+0x40/0x40 [ 1496.714996][ T1577] ? lock_downgrade+0x680/0x680 [ 1496.730888][ T1577] ? wait_for_completion_interruptible+0x340/0x340 [ 1496.747926][ T1577] ? ww_mutex_lock+0x3e/0x380 [ 1496.762482][ T1577] ww_mutex_lock+0x3e/0x380 [ 1496.778844][ T1577] test_cycle_work+0x1bb/0x500 [test_ww_mutex] And, we found that it occasionally hangs on v5.16-rc3 (1/3 runs), below is a good dmesg. [ 962.136756][ T2950] make: Entering directory '/usr/src/perf_selftests-x86_64-rhel-8.3-kselftests-d58071a8a76d779eedab38033ae4c821c30295a5/tools/testing/selftests/locking' [ 962.136831][ T2950]- [ 962.205036][ T2950] TAP version 13 [ 962.206003][ T2950]- [ 962.298458][ T2950] 1..1 [ 962.299657][ T2950]- [ 962.345588][ T2950] # selftests: locking: ww_mutex.sh [ 962.345657][ T2950]- [ 973.641869][T25509] All ww mutex selftests passed [ 973.773996][ T2950] # locking/ww_mutex: ok [ 973.774068][ T2950]- [ 973.774236][ T2960] # locking/ww_mutex: ok [ 973.802355][ T2960]- [ 973.829966][ T2950] ok 1 selftests: locking: ww_mutex.sh [ 973.834748][ T2950]- [ 973.838302][ T2960] ok 1 selftests: locking: ww_mutex.sh [ 973.899815][ T2960]- [ 973.921431][ T2950] make: Leaving directory '/usr/src/perf_selftests-x86_64-rhel-8.3-kselftests-d58071a8a76d779eedab38033ae4c821c30295a5/tools/testing/selftests/locking' [ 973.932312][ T2950]- [ 973.957345][ T2960] make: Leaving directory '/usr/src/perf_selftests-x86_64-rhel-8.3-kselftests-d58071a8a76d779eedab38033ae4c821c30295a5/tools/testing/selftests/locking' Thanks Zhijian@0Day

11 months

3
3
0 0

[PATCH v22 0/5] Implement IOCTL to get and optionally clear info about PTEs

by Muhammad Usama Anjum

Changes in v22: - Interface change: - Replace [start start + len) with [start, end) - Return the ending address of the address walk in start Changes in v21: - Abort walk instead of returning error if WP is to be performed on partial hugetlb *Changes in v20* - Correct PAGE_IS_FILE and add PAGE_IS_PFNZERO *Changes in v19* - Minor changes and interface updates *Changes in v18* - Rebase on top of next-20230613 - Minor updates *Changes in v17* - Rebase on top of next-20230606 - Minor improvements in PAGEMAP_SCAN IOCTL patch *Changes in v16* - Fix a corner case - Add exclusive PM_SCAN_OP_WP back *Changes in v15* - Build fix (Add missed build fix in RESEND) *Changes in v14* - Fix build error caused by #ifdef added at last minute in some configs *Changes in v13* - Rebase on top of next-20230414 - Give-up on using uffd_wp_range() and write new helpers, flush tlb only once *Changes in v12* - Update and other memory types to UFFD_FEATURE_WP_ASYNC - Rebaase on top of next-20230406 - Review updates *Changes in v11* - Rebase on top of next-20230307 - Base patches on UFFD_FEATURE_WP_UNPOPULATED - Do a lot of cosmetic changes and review updates - Remove ENGAGE_WP + !GET operation as it can be performed with UFFDIO_WRITEPROTECT *Changes in v10* - Add specific condition to return error if hugetlb is used with wp async - Move changes in tools/include/uapi/linux/fs.h to separate patch - Add documentation *Changes in v9:* - Correct fault resolution for userfaultfd wp async - Fix build warnings and errors which were happening on some configs - Simplify pagemap ioctl's code *Changes in v8:* - Update uffd async wp implementation - Improve PAGEMAP_IOCTL implementation *Changes in v7:* - Add uffd wp async - Update the IOCTL to use uffd under the hood instead of soft-dirty flags *Motivation* The real motivation for adding PAGEMAP_SCAN IOCTL is to emulate Windows GetWriteWatch() syscall [1]. The GetWriteWatch{} retrieves the addresses of the pages that are written to in a region of virtual memory. This syscall is used in Windows applications and games etc. This syscall is being emulated in pretty slow manner in userspace. Our purpose is to enhance the kernel such that we translate it efficiently in a better way. Currently some out of tree hack patches are being used to efficiently emulate it in some kernels. We intend to replace those with these patches. So the whole gaming on Linux can effectively get benefit from this. It means there would be tons of users of this code. CRIU use case [2] was mentioned by Andrei and Danylo: > Use cases for migrating sparse VMAs are binaries sanitized with ASAN, > MSAN or TSAN [3]. All of these sanitizers produce sparse mappings of > shadow memory [4]. Being able to migrate such binaries allows to highly > reduce the amount of work needed to identify and fix post-migration > crashes, which happen constantly. Andrei's defines the following uses of this code: * it is more granular and allows us to track changed pages more effectively. The current interface can clear dirty bits for the entire process only. In addition, reading info about pages is a separate operation. It means we must freeze the process to read information about all its pages, reset dirty bits, only then we can start dumping pages. The information about pages becomes more and more outdated, while we are processing pages. The new interface solves both these downsides. First, it allows us to read pte bits and clear the soft-dirty bit atomically. It means that CRIU will not need to freeze processes to pre-dump their memory. Second, it clears soft-dirty bits for a specified region of memory. It means CRIU will have actual info about pages to the moment of dumping them. * The new interface has to be much faster because basic page filtering is happening in the kernel. With the old interface, we have to read pagemap for each page. *Implementation Evolution (Short Summary)* From the definition of GetWriteWatch(), we feel like kernel's soft-dirty feature can be used under the hood with some additions like: * reset soft-dirty flag for only a specific region of memory instead of clearing the flag for the entire process * get and clear soft-dirty flag for a specific region atomically So we decided to use ioctl on pagemap file to read or/and reset soft-dirty flag. But using soft-dirty flag, sometimes we get extra pages which weren't even written. They had become soft-dirty because of VMA merging and VM_SOFTDIRTY flag. This breaks the definition of GetWriteWatch(). We were able to by-pass this short coming by ignoring VM_SOFTDIRTY until David reported that mprotect etc messes up the soft-dirty flag while ignoring VM_SOFTDIRTY [5]. This wasn't happening until [6] got introduced. We discussed if we can revert these patches. But we could not reach to any conclusion. So at this point, I made couple of tries to solve this whole VM_SOFTDIRTY issue by correcting the soft-dirty implementation: * [7] Correct the bug fixed wrongly back in 2014. It had potential to cause regression. We left it behind. * [8] Keep a list of soft-dirty part of a VMA across splits and merges. I got the reply don't increase the size of the VMA by 8 bytes. At this point, we left soft-dirty considering it is too much delicate and userfaultfd [9] seemed like the only way forward. From there onward, we have been basing soft-dirty emulation on userfaultfd wp feature where kernel resolves the faults itself when WP_ASYNC feature is used. It was straight forward to add WP_ASYNC feature in userfautlfd. Now we get only those pages dirty or written-to which are really written in reality. (PS There is another WP_UNPOPULATED userfautfd feature is required which is needed to avoid pre-faulting memory before write-protecting [9].) All the different masks were added on the request of CRIU devs to create interface more generic and better. [1] https://learn.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-… [2] https://lore.kernel.org/all/20221014134802.1361436-1-mdanylo@google.com [3] https://github.com/google/sanitizers [4] https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm#64-bit [5] https://lore.kernel.org/all/bfcae708-db21-04b4-0bbe-712badd03071@redhat.com [6] https://lore.kernel.org/all/20220725142048.30450-1-peterx@redhat.com/ [7] https://lore.kernel.org/all/20221122115007.2787017-1-usama.anjum@collabora.… [8] https://lore.kernel.org/all/20221220162606.1595355-1-usama.anjum@collabora.… [9] https://lore.kernel.org/all/20230306213925.617814-1-peterx@redhat.com [10] https://lore.kernel.org/all/20230125144529.1630917-1-mdanylo@google.com * Original Cover letter from v8* Hello, Note: Soft-dirty pages and pages which have been written-to are synonyms. As kernel already has soft-dirty feature inside which we have given up to use, we are using written-to terminology while using UFFD async WP under the hood. This IOCTL, PAGEMAP_SCAN on pagemap file can be used to get and/or clear the info about page table entries. The following operations are supported in this ioctl: - Get the information if the pages have been written-to (PAGE_IS_WRITTEN), file mapped (PAGE_IS_FILE), present (PAGE_IS_PRESENT) or swapped (PAGE_IS_SWAPPED). - Write-protect the pages (PAGEMAP_WP_ENGAGE) to start finding which pages have been written-to. - Find pages which have been written-to and write protect the pages (atomic PAGE_IS_WRITTEN + PAGEMAP_WP_ENGAGE) It is possible to find and clear soft-dirty pages entirely in userspace. But it isn't efficient: - The mprotect and SIGSEGV handler for bookkeeping - The userfaultfd wp (synchronous) with the handler for bookkeeping Some benchmarks can be seen here[1]. This series adds features that weren't present earlier: - There is no atomic get soft-dirty/Written-to status and clear present in the kernel. - The pages which have been written-to can not be found in accurate way. (Kernel's soft-dirty PTE bit + sof_dirty VMA bit shows more soft-dirty pages than there actually are.) Historically, soft-dirty PTE bit tracking has been used in the CRIU project. The procfs interface is enough for finding the soft-dirty bit status and clearing the soft-dirty bit of all the pages of a process. We have the use case where we need to track the soft-dirty PTE bit for only specific pages on-demand. We need this tracking and clear mechanism of a region of memory while the process is running to emulate the getWriteWatch() syscall of Windows. *(Moved to using UFFD instead of soft-dirtyi feature to find pages which have been written-to from v7 patch series)*: Stop using the soft-dirty flags for finding which pages have been written to. It is too delicate and wrong as it shows more soft-dirty pages than the actual soft-dirty pages. There is no interest in correcting it [2][3] as this is how the feature was written years ago. It shouldn't be updated to changed behaviour. Peter Xu has suggested using the async version of the UFFD WP [4] as it is based inherently on the PTEs. So in this patch series, I've added a new mode to the UFFD which is asynchronous version of the write protect. When this variant of the UFFD WP is used, the page faults are resolved automatically by the kernel. The pages which have been written-to can be found by reading pagemap file (!PM_UFFD_WP). This feature can be used successfully to find which pages have been written to from the time the pages were write protected. This works just like the soft-dirty flag without showing any extra pages which aren't soft-dirty in reality. The information related to pages if the page is file mapped, present and swapped is required for the CRIU project [5][6]. The addition of the required mask, any mask, excluded mask and return masks are also required for the CRIU project [5]. The IOCTL returns the addresses of the pages which match the specific masks. The page addresses are returned in struct page_region in a compact form. The max_pages is needed to support a use case where user only wants to get a specific number of pages. So there is no need to find all the pages of interest in the range when max_pages is specified. The IOCTL returns when the maximum number of the pages are found. The max_pages is optional. If max_pages is specified, it must be equal or greater than the vec_size. This restriction is needed to handle worse case when one page_region only contains info of one page and it cannot be compacted. This is needed to emulate the Windows getWriteWatch() syscall. The patch series include the detailed selftest which can be used as an example for the uffd async wp test and PAGEMAP_IOCTL. It shows the interface usages as well. [1] https://lore.kernel.org/lkml/54d4c322-cd6e-eefd-b161-2af2b56aae24@collabora… [2] https://lore.kernel.org/all/20221220162606.1595355-1-usama.anjum@collabora.… [3] https://lore.kernel.org/all/20221122115007.2787017-1-usama.anjum@collabora.… [4] https://lore.kernel.org/all/Y6Hc2d+7eTKs7AiH@x1n [5] https://lore.kernel.org/all/YyiDg79flhWoMDZB@gmail.com/ [6] https://lore.kernel.org/all/20221014134802.1361436-1-mdanylo@google.com/ Regards, Muhammad Usama Anjum Muhammad Usama Anjum (4): fs/proc/task_mmu: Implement IOCTL to get and optionally clear info about PTEs tools headers UAPI: Update linux/fs.h with the kernel sources mm/pagemap: add documentation of PAGEMAP_SCAN IOCTL selftests: mm: add pagemap ioctl tests Peter Xu (1): userfaultfd: UFFD_FEATURE_WP_ASYNC Documentation/admin-guide/mm/pagemap.rst | 58 + Documentation/admin-guide/mm/userfaultfd.rst | 35 + fs/proc/task_mmu.c | 565 +++++++ fs/userfaultfd.c | 26 +- include/linux/hugetlb.h | 1 + include/linux/userfaultfd_k.h | 21 +- include/uapi/linux/fs.h | 55 + include/uapi/linux/userfaultfd.h | 9 +- mm/hugetlb.c | 34 +- mm/memory.c | 27 +- tools/include/uapi/linux/fs.h | 55 + tools/testing/selftests/mm/.gitignore | 2 + tools/testing/selftests/mm/Makefile | 3 +- tools/testing/selftests/mm/config | 1 + tools/testing/selftests/mm/pagemap_ioctl.c | 1464 ++++++++++++++++++ tools/testing/selftests/mm/run_vmtests.sh | 4 + 16 files changed, 2336 insertions(+), 24 deletions(-) create mode 100644 tools/testing/selftests/mm/pagemap_ioctl.c mode change 100644 => 100755 tools/testing/selftests/mm/run_vmtests.sh -- 2.39.2

11 months

4
13
0 0

[PATCH v2 1/6] mm: userfaultfd: add new UFFDIO_POISON ioctl

by Axel Rasmussen

The basic idea here is to "simulate" memory poisoning for VMs. A VM running on some host might encounter a memory error, after which some page(s) are poisoned (i.e., future accesses SIGBUS). They expect that once poisoned, pages can never become "un-poisoned". So, when we live migrate the VM, we need to preserve the poisoned status of these pages. When live migrating, we try to get the guest running on its new host as quickly as possible. So, we start it running before all memory has been copied, and before we're certain which pages should be poisoned or not. So the basic way to use this new feature is: - On the new host, the guest's memory is registered with userfaultfd, in either MISSING or MINOR mode (doesn't really matter for this purpose). - On any first access, we get a userfaultfd event. At this point we can communicate with the old host to find out if the page was poisoned. - If so, we can respond with a UFFDIO_POISON - this places a swap marker so any future accesses will SIGBUS. Because the pte is now "present", future accesses won't generate more userfaultfd events, they'll just SIGBUS directly. UFFDIO_POISON does not handle unmapping previously-present PTEs. This isn't needed, because during live migration we want to intercept all accesses with userfaultfd (not just writes, so WP mode isn't useful for this). So whether minor or missing mode is being used (or both), the PTE won't be present in any case, so handling that case isn't needed. Why return VM_FAULT_HWPOISON instead of VM_FAULT_SIGBUS when one of these markers is encountered? For "normal" userspace programs there isn't a big difference, both yield a SIGBUS. The difference for KVM is key though: VM_FAULT_HWPOISON will result in an MCE being injected into the guest (which is the behavior we want). With VM_FAULT_SIGBUS, the hypervisor would need to catch the SIGBUS and deal with the MCE injection itself. Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com> --- fs/userfaultfd.c | 63 ++++++++++++++++++++++++++++++++ include/linux/swapops.h | 3 +- include/linux/userfaultfd_k.h | 4 ++ include/uapi/linux/userfaultfd.h | 25 +++++++++++-- mm/memory.c | 4 ++ mm/userfaultfd.c | 62 ++++++++++++++++++++++++++++++- 6 files changed, 156 insertions(+), 5 deletions(-) diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 7cecd49e078b..c26a883399c9 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1965,6 +1965,66 @@ static int userfaultfd_continue(struct userfaultfd_ctx *ctx, unsigned long arg) return ret; } +static inline int userfaultfd_poison(struct userfaultfd_ctx *ctx, unsigned long arg) +{ + __s64 ret; + struct uffdio_poison uffdio_poison; + struct uffdio_poison __user *user_uffdio_poison; + struct userfaultfd_wake_range range; + + user_uffdio_poison = (struct uffdio_poison __user *)arg; + + ret = -EAGAIN; + if (atomic_read(&ctx->mmap_changing)) + goto out; + + ret = -EFAULT; + if (copy_from_user(&uffdio_poison, user_uffdio_poison, + /* don't copy the output fields */ + sizeof(uffdio_poison) - (sizeof(__s64)))) + goto out; + + ret = validate_range(ctx->mm, uffdio_poison.range.start, + uffdio_poison.range.len); + if (ret) + goto out; + + ret = -EINVAL; + /* double check for wraparound just in case. */ + if (uffdio_poison.range.start + uffdio_poison.range.len <= + uffdio_poison.range.start) { + goto out; + } + if (uffdio_poison.mode & ~UFFDIO_POISON_MODE_DONTWAKE) + goto out; + + if (mmget_not_zero(ctx->mm)) { + ret = mfill_atomic_poison(ctx->mm, uffdio_poison.range.start, + uffdio_poison.range.len, + &ctx->mmap_changing, 0); + mmput(ctx->mm); + } else { + return -ESRCH; + } + + if (unlikely(put_user(ret, &user_uffdio_poison->updated))) + return -EFAULT; + if (ret < 0) + goto out; + + /* len == 0 would wake all */ + BUG_ON(!ret); + range.len = ret; + if (!(uffdio_poison.mode & UFFDIO_POISON_MODE_DONTWAKE)) { + range.start = uffdio_poison.range.start; + wake_userfault(ctx, &range); + } + ret = range.len == uffdio_poison.range.len ? 0 : -EAGAIN; + +out: + return ret; +} + static inline unsigned int uffd_ctx_features(__u64 user_features) { /* @@ -2066,6 +2126,9 @@ static long userfaultfd_ioctl(struct file *file, unsigned cmd, case UFFDIO_CONTINUE: ret = userfaultfd_continue(ctx, arg); break; + case UFFDIO_POISON: + ret = userfaultfd_poison(ctx, arg); + break; } return ret; } diff --git a/include/linux/swapops.h b/include/linux/swapops.h index 4c932cb45e0b..8259fee32421 100644 --- a/include/linux/swapops.h +++ b/include/linux/swapops.h @@ -394,7 +394,8 @@ typedef unsigned long pte_marker; #define PTE_MARKER_UFFD_WP BIT(0) #define PTE_MARKER_SWAPIN_ERROR BIT(1) -#define PTE_MARKER_MASK (BIT(2) - 1) +#define PTE_MARKER_UFFD_POISON BIT(2) +#define PTE_MARKER_MASK (BIT(3) - 1) static inline swp_entry_t make_pte_marker_entry(pte_marker marker) { diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index ac7b0c96d351..ac8c6854097c 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -46,6 +46,7 @@ enum mfill_atomic_mode { MFILL_ATOMIC_COPY, MFILL_ATOMIC_ZEROPAGE, MFILL_ATOMIC_CONTINUE, + MFILL_ATOMIC_POISON, NR_MFILL_ATOMIC_MODES, }; @@ -83,6 +84,9 @@ extern ssize_t mfill_atomic_zeropage(struct mm_struct *dst_mm, extern ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long len, atomic_t *mmap_changing, uffd_flags_t flags); +extern ssize_t mfill_atomic_poison(struct mm_struct *dst_mm, unsigned long start, + unsigned long len, atomic_t *mmap_changing, + uffd_flags_t flags); extern int mwriteprotect_range(struct mm_struct *dst_mm, unsigned long start, unsigned long len, bool enable_wp, atomic_t *mmap_changing); diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h index 66dd4cd277bd..62151706c5a3 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -39,7 +39,8 @@ UFFD_FEATURE_MINOR_SHMEM | \ UFFD_FEATURE_EXACT_ADDRESS | \ UFFD_FEATURE_WP_HUGETLBFS_SHMEM | \ - UFFD_FEATURE_WP_UNPOPULATED) + UFFD_FEATURE_WP_UNPOPULATED | \ + UFFD_FEATURE_POISON) #define UFFD_API_IOCTLS \ ((__u64)1 << _UFFDIO_REGISTER | \ (__u64)1 << _UFFDIO_UNREGISTER | \ @@ -49,12 +50,14 @@ (__u64)1 << _UFFDIO_COPY | \ (__u64)1 << _UFFDIO_ZEROPAGE | \ (__u64)1 << _UFFDIO_WRITEPROTECT | \ - (__u64)1 << _UFFDIO_CONTINUE) + (__u64)1 << _UFFDIO_CONTINUE | \ + (__u64)1 << _UFFDIO_POISON) #define UFFD_API_RANGE_IOCTLS_BASIC \ ((__u64)1 << _UFFDIO_WAKE | \ (__u64)1 << _UFFDIO_COPY | \ + (__u64)1 << _UFFDIO_WRITEPROTECT | \ (__u64)1 << _UFFDIO_CONTINUE | \ - (__u64)1 << _UFFDIO_WRITEPROTECT) + (__u64)1 << _UFFDIO_POISON) /* * Valid ioctl command number range with this API is from 0x00 to @@ -71,6 +74,7 @@ #define _UFFDIO_ZEROPAGE (0x04) #define _UFFDIO_WRITEPROTECT (0x06) #define _UFFDIO_CONTINUE (0x07) +#define _UFFDIO_POISON (0x08) #define _UFFDIO_API (0x3F) /* userfaultfd ioctl ids */ @@ -91,6 +95,8 @@ struct uffdio_writeprotect) #define UFFDIO_CONTINUE _IOWR(UFFDIO, _UFFDIO_CONTINUE, \ struct uffdio_continue) +#define UFFDIO_POISON _IOWR(UFFDIO, _UFFDIO_POISON, \ + struct uffdio_poison) /* read() structure */ struct uffd_msg { @@ -225,6 +231,7 @@ struct uffdio_api { #define UFFD_FEATURE_EXACT_ADDRESS (1<<11) #define UFFD_FEATURE_WP_HUGETLBFS_SHMEM (1<<12) #define UFFD_FEATURE_WP_UNPOPULATED (1<<13) +#define UFFD_FEATURE_POISON (1<<14) __u64 features; __u64 ioctls; @@ -321,6 +328,18 @@ struct uffdio_continue { __s64 mapped; }; +struct uffdio_poison { + struct uffdio_range range; +#define UFFDIO_POISON_MODE_DONTWAKE ((__u64)1<<0) + __u64 mode; + + /* + * Fields below here are written by the ioctl and must be at the end: + * the copy_from_user will not read past here. + */ + __s64 updated; +}; + /* * Flags for the userfaultfd(2) system call itself. */ diff --git a/mm/memory.c b/mm/memory.c index d8a9a770b1f1..7fbda39e060d 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3692,6 +3692,10 @@ static vm_fault_t handle_pte_marker(struct vm_fault *vmf) if (WARN_ON_ONCE(!marker)) return VM_FAULT_SIGBUS; + /* Poison emulation explicitly requested for this PTE. */ + if (marker & PTE_MARKER_UFFD_POISON) + return VM_FAULT_HWPOISON; + /* Higher priority than uffd-wp when data corrupted */ if (marker & PTE_MARKER_SWAPIN_ERROR) return VM_FAULT_SIGBUS; diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index a2bf37ee276d..87b62ca1e09e 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -286,6 +286,51 @@ static int mfill_atomic_pte_continue(pmd_t *dst_pmd, goto out; } +/* Handles UFFDIO_POISON for all non-hugetlb VMAs. */ +static int mfill_atomic_pte_poison(pmd_t *dst_pmd, + struct vm_area_struct *dst_vma, + unsigned long dst_addr, + uffd_flags_t flags) +{ + int ret; + struct mm_struct *dst_mm = dst_vma->vm_mm; + pte_t _dst_pte, *dst_pte; + spinlock_t *ptl; + + _dst_pte = make_pte_marker(PTE_MARKER_UFFD_POISON); + dst_pte = pte_offset_map_lock(dst_mm, dst_pmd, dst_addr, &ptl); + + if (vma_is_shmem(dst_vma)) { + struct inode *inode; + pgoff_t offset, max_off; + + /* serialize against truncate with the page table lock */ + inode = dst_vma->vm_file->f_inode; + offset = linear_page_index(dst_vma, dst_addr); + max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); + ret = -EFAULT; + if (unlikely(offset >= max_off)) + goto out_unlock; + } + + ret = -EEXIST; + /* + * For now, we don't handle unmapping pages, so only support filling in + * none PTEs, or replacing PTE markers. + */ + if (!pte_none_mostly(*dst_pte)) + goto out_unlock; + + set_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte); + + /* No need to invalidate - it was non-present before */ + update_mmu_cache(dst_vma, dst_addr, dst_pte); + ret = 0; +out_unlock: + pte_unmap_unlock(dst_pte, ptl); + return ret; +} + static pmd_t *mm_alloc_pmd(struct mm_struct *mm, unsigned long address) { pgd_t *pgd; @@ -336,8 +381,12 @@ static __always_inline ssize_t mfill_atomic_hugetlb( * supported by hugetlb. A PMD_SIZE huge pages may exist as used * by THP. Since we can not reliably insert a zero page, this * feature is not supported. + * + * PTE marker handling for hugetlb is a bit special, so for now + * UFFDIO_POISON is not supported. */ - if (uffd_flags_mode_is(flags, MFILL_ATOMIC_ZEROPAGE)) { + if (uffd_flags_mode_is(flags, MFILL_ATOMIC_ZEROPAGE) || + uffd_flags_mode_is(flags, MFILL_ATOMIC_POISON)) { mmap_read_unlock(dst_mm); return -EINVAL; } @@ -481,6 +530,9 @@ static __always_inline ssize_t mfill_atomic_pte(pmd_t *dst_pmd, if (uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE)) { return mfill_atomic_pte_continue(dst_pmd, dst_vma, dst_addr, flags); + } else if (uffd_flags_mode_is(flags, MFILL_ATOMIC_POISON)) { + return mfill_atomic_pte_poison(dst_pmd, dst_vma, + dst_addr, flags); } /* @@ -702,6 +754,14 @@ ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long start, uffd_flags_set_mode(flags, MFILL_ATOMIC_CONTINUE)); } +ssize_t mfill_atomic_poison(struct mm_struct *dst_mm, unsigned long start, + unsigned long len, atomic_t *mmap_changing, + uffd_flags_t flags) +{ + return mfill_atomic(dst_mm, start, 0, len, mmap_changing, + uffd_flags_set_mode(flags, MFILL_ATOMIC_POISON)); +} + long uffd_wp_range(struct vm_area_struct *dst_vma, unsigned long start, unsigned long len, bool enable_wp) { -- 2.41.0.255.g8b1d071c50-goog

11 months

5
22
0 0

[PATCH] kunit: tool: undo type subscripts for subprocess.Popen

by Daniel Latypov

Writing `subprocess.Popen[str]` requires python 3.9+. kunit.py has an assertion that the python version is 3.7+, so we should try to stay backwards compatible. This conflicts a bit with commit 1da2e6220e11 ("kunit: tool: fix pre-existing `mypy --strict` errors and update run_checks.py"), since mypy complains like so > kunit_kernel.py:95: error: Missing type parameters for generic type "Popen" [type-arg] Note: `mypy --strict --python-version 3.7` does not work. We could annotate each file with comments like `# mypy: disable-error-code="type-arg" but then we might still get nudged to break back-compat in other files. This patch adds a `mypy.ini` file since it seems like the only way to disable specific error codes for all our files. Note: run_checks.py doesn't need to specify `--config_file mypy.ini`, but I think being explicit is better, particularly since most kernel devs won't be familiar with how mypy works. Fixes: 695e26030858 ("kunit: tool: add subscripts for type annotations where appropriate") Reported-by: SeongJae Park <sj(a)kernel.org> Link: https://lore.kernel.org/linux-kselftest/20230501171520.138753-1-sj@kernel.o… Signed-off-by: Daniel Latypov <dlatypov(a)google.com> --- tools/testing/kunit/kunit_kernel.py | 6 +++--- tools/testing/kunit/mypy.ini | 6 ++++++ tools/testing/kunit/run_checks.py | 2 +- 3 files changed, 10 insertions(+), 4 deletions(-) create mode 100644 tools/testing/kunit/mypy.ini diff --git a/tools/testing/kunit/kunit_kernel.py b/tools/testing/kunit/kunit_kernel.py index f01f94106129..7f648802caf6 100644 --- a/tools/testing/kunit/kunit_kernel.py +++ b/tools/testing/kunit/kunit_kernel.py @@ -92,7 +92,7 @@ class LinuxSourceTreeOperations: if stderr: # likely only due to build warnings print(stderr.decode()) - def start(self, params: List[str], build_dir: str) -> subprocess.Popen[str]: + def start(self, params: List[str], build_dir: str) -> subprocess.Popen: raise RuntimeError('not implemented!') @@ -113,7 +113,7 @@ class LinuxSourceTreeOperationsQemu(LinuxSourceTreeOperations): kconfig.merge_in_entries(base_kunitconfig) return kconfig - def start(self, params: List[str], build_dir: str) -> subprocess.Popen[str]: + def start(self, params: List[str], build_dir: str) -> subprocess.Popen: kernel_path = os.path.join(build_dir, self._kernel_path) qemu_command = ['qemu-system-' + self._qemu_arch, '-nodefaults', @@ -142,7 +142,7 @@ class LinuxSourceTreeOperationsUml(LinuxSourceTreeOperations): kconfig.merge_in_entries(base_kunitconfig) return kconfig - def start(self, params: List[str], build_dir: str) -> subprocess.Popen[str]: + def start(self, params: List[str], build_dir: str) -> subprocess.Popen: """Runs the Linux UML binary. Must be named 'linux'.""" linux_bin = os.path.join(build_dir, 'linux') params.extend(['mem=1G', 'console=tty', 'kunit_shutdown=halt']) diff --git a/tools/testing/kunit/mypy.ini b/tools/testing/kunit/mypy.ini new file mode 100644 index 000000000000..ddd288309efa --- /dev/null +++ b/tools/testing/kunit/mypy.ini @@ -0,0 +1,6 @@ +[mypy] +strict = True + +# E.g. we can't write subprocess.Popen[str] until Python 3.9+. +# But kunit.py tries to support Python 3.7+, so let's disable it. +disable_error_code = type-arg diff --git a/tools/testing/kunit/run_checks.py b/tools/testing/kunit/run_checks.py index 8208c3b3135e..c6d494ea3373 100755 --- a/tools/testing/kunit/run_checks.py +++ b/tools/testing/kunit/run_checks.py @@ -23,7 +23,7 @@ commands: Dict[str, Sequence[str]] = { 'kunit_tool_test.py': ['./kunit_tool_test.py'], 'kunit smoke test': ['./kunit.py', 'run', '--kunitconfig=lib/kunit', '--build_dir=kunit_run_checks'], 'pytype': ['/bin/sh', '-c', 'pytype *.py'], - 'mypy': ['mypy', '--strict', '--exclude', '_test.py$', '--exclude', 'qemu_configs/', '.'], + 'mypy': ['mypy', '--config-file', 'mypy.ini', '--exclude', '_test.py$', '--exclude', 'qemu_configs/', '.'], } # The user might not have mypy or pytype installed, skip them if so. base-commit: a42077b787680cbc365a96446b30f32399fa3f6f -- 2.40.1.495.gc816e09b53d-goog

11 months

4
8
0 0

[PATCH v3 00/10] tracing: introducing eventfs

by Ajay Kaher

Events Tracing infrastructure contains lot of files, directories (internally in terms of inodes, dentries). And ends up by consuming memory in MBs. We can have multiple events of Events Tracing, which further requires more memory. Instead of creating inodes/dentries, eventfs could keep meta-data and skip the creation of inodes/dentries. As and when require, eventfs will create the inodes/dentries only for required files/directories. Also eventfs would delete the inodes/dentries once no more requires but preserve the meta data. Tracing events took ~9MB, with this approach it took ~4.5MB for ~10K files/dir. v2: Patch 01: new patch:'Require all trace events to have a TRACE_SYSTEM' Patch 02: moved from v1 1/9 Patch 03: moved from v1 2/9 As suggested by Zheng Yejian, introduced eventfs_prepare_ef() helper function to add files or directories to eventfs fix WARNING reported by kernel test robot in v1 8/9 Patch 04: moved from v1 3/9 used eventfs_prepare_ef() to add files fix WARNING reported by kernel test robot in v1 8/9 Patch 05: moved from v1 4/9 fix compiling warning reported by kernel test robot in v1 4/9 Patch 06: moved from v1 5/9 Patch 07: moved from v1 6/9 Patch 08: moved from v1 7/9 Patch 09: moved from v1 8/9 rebased because of v3 01/10 Patch 10: moved from v1 9/9 v1: Patch 1: add header file Patch 2: resolved kernel test robot issues protecting eventfs lists using nested eventfs_rwsem Patch 3: protecting eventfs lists using nested eventfs_rwsem Patch 4: improve events cleanup code to fix crashes Patch 5: resolved kernel test robot issues removed d_instantiate_anon() calls Patch 6: resolved kernel test robot issues fix kprobe test in eventfs_root_lookup() protecting eventfs lists using nested eventfs_rwsem Patch 7: remove header file Patch 8: pass eventfs_rwsem as argument to eventfs functions called eventfs_remove_events_dir() instead of tracefs_remove() from event_trace_del_tracer() Patch 9: new patch to fix kprobe test case fs/tracefs/Makefile | 1 + fs/tracefs/event_inode.c | 757 ++++++++++++++++++ fs/tracefs/inode.c | 124 ++- fs/tracefs/internal.h | 25 + include/linux/trace_events.h | 1 + include/linux/tracefs.h | 49 ++ kernel/trace/trace.h | 3 +- kernel/trace/trace_events.c | 78 +- .../ftrace/test.d/kprobe/kprobe_args_char.tc | 4 +- .../test.d/kprobe/kprobe_args_string.tc | 4 +- 10 files changed, 994 insertions(+), 52 deletions(-) create mode 100644 fs/tracefs/event_inode.c create mode 100644 fs/tracefs/internal.h -- 2.40.0

11 months

3
23
0 0

[PATCH v2 0/3] selftests/nolibc: improve test report support

by Zhangjin Wu

Hi, Willy Here is the v2 of our old patchset about test report [1]. The trailing '\r' fixup has been merged, so, here only resend the left parts with an additional patch to restore the failed tests print. This patchset is rebased on the dev.2023.06.14a branch of linux-rcu [2]. Tests have passed for 'x86 run': 138 test(s) passed, 0 skipped, 0 failed. See all results in /labs/linux-lab/src/linux-stable/tools/testing/selftests/nolibc/run.out Also did 'run-user' for x86, mips and arm64. Changes from v1 -> v2: 1. selftests/nolibc: add a standalone test report macro As Willy pointed out, the old method with additional test-report target not work in 'make -j'. A new macro is added to share the same report logic among the run-user, run and rerun targets, the path to test log file is 2. selftests/nolibc: always print the path to test log file Always print the path to test log file, but move it to a new line to avoid annoying people when the test pass without any failures. 3. selftests/nolibc: restore the failed tests print Restore printing of the failed tests to avoid manually opening the test log file when there are really failues. Best regards, Zhangjin --- [1]: https://lore.kernel.org/lkml/cover.1685936428.git.falcon@tinylab.org/ [2]: https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/ Zhangjin Wu (3): selftests/nolibc: add a standalone test report macro selftests/nolibc: always print the path to test log file selftests/nolibc: restore the failed tests print tools/testing/selftests/nolibc/Makefile | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) -- 2.25.1

11 months

2
5
0 0

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