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2022-12-27selftests/rseq: arm64: Template memory ordering and percpu access modeMathieu Desnoyers
Introduce a rseq-arm64-bits.h template header which is internally included to generate the static inline functions covering: - relaxed and release memory ordering, - per-cpu-id and per-mm-cid per-cpu data access. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-14-mathieu.desnoyers@efficios.com
2022-12-27selftests/rseq: arm: Template memory ordering and percpu access modeMathieu Desnoyers
Introduce a rseq-arm-bits.h template header which is internally included to generate the static inline functions covering: - relaxed and release memory ordering, - per-cpu-id and per-mm-cid per-cpu data access. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-13-mathieu.desnoyers@efficios.com
2022-12-27selftests/rseq: x86: Template memory ordering and percpu access modeMathieu Desnoyers
Introduce a rseq-x86-bits.h template header which is internally included to generate the static inline functions covering: - relaxed and release memory ordering, - per-cpu-id and per-mm-cid per-cpu data access. This introduces changes to the rseq.h selftests API which require to update the rseq selftest programs. Similar API/templating changes need to be done for other architectures. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-12-mathieu.desnoyers@efficios.com
2022-12-27selftests/rseq: Implement rseq mm_cid field supportMathieu Desnoyers
Add support for the mm_cid field (per-memory-map concurrency ID) of struct rseq to rseq selftests. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-11-mathieu.desnoyers@efficios.com
2022-12-27selftests/rseq: Remove RSEQ_SKIP_FASTPATH codeMathieu Desnoyers
This code is not currently build by the test Makefile, adds complexity, and is not overall useful considering that the abort handling loops to retry the fast-path. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-10-mathieu.desnoyers@efficios.com
2022-12-27rseq: Extend struct rseq with per-memory-map concurrency IDMathieu Desnoyers
If a memory map has fewer threads than there are cores on the system, or is limited to run on few cores concurrently through sched affinity or cgroup cpusets, the concurrency IDs will be values close to 0, thus allowing efficient use of user-space memory for per-cpu data structures. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-9-mathieu.desnoyers@efficios.com
2022-12-27sched: Introduce per-memory-map concurrency IDMathieu Desnoyers
This feature allows the scheduler to expose a per-memory map concurrency ID to user-space. This concurrency ID is within the possible cpus range, and is temporarily (and uniquely) assigned while threads are actively running within a memory map. If a memory map has fewer threads than cores, or is limited to run on few cores concurrently through sched affinity or cgroup cpusets, the concurrency IDs will be values close to 0, thus allowing efficient use of user-space memory for per-cpu data structures. This feature is meant to be exposed by a new rseq thread area field. The primary purpose of this feature is to do the heavy-lifting needed by memory allocators to allow them to use per-cpu data structures efficiently in the following situations: - Single-threaded applications, - Multi-threaded applications on large systems (many cores) with limited cpu affinity mask, - Multi-threaded applications on large systems (many cores) with restricted cgroup cpuset per container. One of the key concern from scheduler maintainers is the overhead associated with additional spin locks or atomic operations in the scheduler fast-path. This is why the following optimization is implemented. On context switch between threads belonging to the same memory map, transfer the mm_cid from prev to next without any atomic ops. This takes care of use-cases involving frequent context switch between threads belonging to the same memory map. Additional optimizations can be done if the spin locks added when context switching between threads belonging to different memory maps end up being a performance bottleneck. Those are left out of this patch though. A performance impact would have to be clearly demonstrated to justify the added complexity. The credit goes to Paul Turner (Google) for the original virtual cpu id idea. This feature is implemented based on the discussions with Paul Turner and Peter Oskolkov (Google), but I took the liberty to implement scheduler fast-path optimizations and my own NUMA-awareness scheme. The rumor has it that Google have been running a rseq vcpu_id extension internally in production for a year. The tcmalloc source code indeed has comments hinting at a vcpu_id prototype extension to the rseq system call [1]. The following benchmarks do not show any significant overhead added to the scheduler context switch by this feature: * perf bench sched messaging (process) Baseline: 86.5±0.3 ms With mm_cid: 86.7±2.6 ms * perf bench sched messaging (threaded) Baseline: 84.3±3.0 ms With mm_cid: 84.7±2.6 ms * hackbench (process) Baseline: 82.9±2.7 ms With mm_cid: 82.9±2.9 ms * hackbench (threaded) Baseline: 85.2±2.6 ms With mm_cid: 84.4±2.9 ms [1] https://github.com/google/tcmalloc/blob/master/tcmalloc/internal/linux_syscall_support.h#L26 Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-8-mathieu.desnoyers@efficios.com
2022-12-27selftests/rseq: Implement rseq numa node id field selftestMathieu Desnoyers
Test the NUMA node id extension rseq field. Compare it against the value returned by the getcpu(2) system call while pinned on a specific core. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-7-mathieu.desnoyers@efficios.com
2022-12-27selftests/rseq: Use ELF auxiliary vector for extensible rseqMathieu Desnoyers
Use the ELF auxiliary vector AT_RSEQ_FEATURE_SIZE to detect the RSEQ features supported by the kernel. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-6-mathieu.desnoyers@efficios.com
2022-12-27rseq: Extend struct rseq with numa node idMathieu Desnoyers
Adding the NUMA node id to struct rseq is a straightforward thing to do, and a good way to figure out if anything in the user-space ecosystem prevents extending struct rseq. This NUMA node id field allows memory allocators such as tcmalloc to take advantage of fast access to the current NUMA node id to perform NUMA-aware memory allocation. It can also be useful for implementing fast-paths for NUMA-aware user-space mutexes. It also allows implementing getcpu(2) purely in user-space. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-5-mathieu.desnoyers@efficios.com
2022-12-27rseq: Introduce extensible rseq ABIMathieu Desnoyers
Introduce the extensible rseq ABI, where the feature size supported by the kernel and the required alignment are communicated to user-space through ELF auxiliary vectors. This allows user-space to call rseq registration with a rseq_len of either 32 bytes for the original struct rseq size (which includes padding), or larger. If rseq_len is larger than 32 bytes, then it must be large enough to contain the feature size communicated to user-space through ELF auxiliary vectors. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-4-mathieu.desnoyers@efficios.com
2022-12-27rseq: Introduce feature size and alignment ELF auxiliary vector entriesMathieu Desnoyers
Export the rseq feature size supported by the kernel as well as the required allocation alignment for the rseq per-thread area to user-space through ELF auxiliary vector entries. This is part of the extensible rseq ABI. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-3-mathieu.desnoyers@efficios.com
2022-12-27selftests/rseq: Fix: Fail thread registration when CONFIG_RSEQ=nMathieu Desnoyers
When linking the selftests against a libc which does not handle rseq registration (before 2.35), rseq thread registration silently succeed even with CONFIG_RSEQ=n because it erroneously thinks that libc is handling rseq registration. This is caused by setting the rseq ownership flag only after the rseq_available() check. It should rather be set before the rseq_available() check. Set the rseq_size to 0 (error value) immediately after the rseq_available() check fails rather than in the thread registration functions. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-2-mathieu.desnoyers@efficios.com
2022-12-27sched: Async unthrottling for cfs bandwidthJosh Don
CFS bandwidth currently distributes new runtime and unthrottles cfs_rq's inline in an hrtimer callback. Runtime distribution is a per-cpu operation, and unthrottling is a per-cgroup operation, since a tg walk is required. On machines with a large number of cpus and large cgroup hierarchies, this cpus*cgroups work can be too much to do in a single hrtimer callback: since IRQ are disabled, hard lockups may easily occur. Specifically, we've found this scalability issue on configurations with 256 cpus, O(1000) cgroups in the hierarchy being throttled, and high memory bandwidth usage. To fix this, we can instead unthrottle cfs_rq's asynchronously via a CSD. Each cpu is responsible for unthrottling itself, thus sharding the total work more fairly across the system, and avoiding hard lockups. Signed-off-by: Josh Don <joshdon@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20221117005418.3499691-1-joshdon@google.com
2022-12-27sched/topology: Add __init for init_defrootdomainBing Huang
init_defrootdomain is only used in initialization Signed-off-by: Bing Huang <huangbing@kylinos.cn> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Valentin Schneider <vschneid@redhat.com> Link: https://lkml.kernel.org/r/20221118034208.267330-1-huangbing775@126.com
2022-12-27futex: Fix futex_waitv() hrtimer debug object leak on kcalloc errorMathieu Desnoyers
In a scenario where kcalloc() fails to allocate memory, the futex_waitv system call immediately returns -ENOMEM without invoking destroy_hrtimer_on_stack(). When CONFIG_DEBUG_OBJECTS_TIMERS=y, this results in leaking a timer debug object. Fixes: bf69bad38cf6 ("futex: Implement sys_futex_waitv()") Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Cc: stable@vger.kernel.org Cc: stable@vger.kernel.org # v5.16+ Link: https://lore.kernel.org/r/20221214222008.200393-1-mathieu.desnoyers@efficios.com
2022-12-27x86/kprobes: Fix optprobe optimization check with CONFIG_RETHUNKMasami Hiramatsu (Google)
Since the CONFIG_RETHUNK and CONFIG_SLS will use INT3 for stopping speculative execution after function return, kprobe jump optimization always fails on the functions with such INT3 inside the function body. (It already checks the INT3 padding between functions, but not inside the function) To avoid this issue, as same as kprobes, check whether the INT3 comes from kgdb or not, and if so, stop decoding and make it fail. The other INT3 will come from CONFIG_RETHUNK/CONFIG_SLS and those can be treated as a one-byte instruction. Fixes: e463a09af2f0 ("x86: Add straight-line-speculation mitigation") Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/167146051929.1374301.7419382929328081706.stgit@devnote3
2022-12-27x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNKMasami Hiramatsu (Google)
Since the CONFIG_RETHUNK and CONFIG_SLS will use INT3 for stopping speculative execution after RET instruction, kprobes always failes to check the probed instruction boundary by decoding the function body if the probed address is after such sequence. (Note that some conditional code blocks will be placed after function return, if compiler decides it is not on the hot path.) This is because kprobes expects kgdb puts the INT3 as a software breakpoint and it will replace the original instruction. But these INT3 are not such purpose, it doesn't need to recover the original instruction. To avoid this issue, kprobes checks whether the INT3 is owned by kgdb or not, and if so, stop decoding and make it fail. The other INT3 will come from CONFIG_RETHUNK/CONFIG_SLS and those can be treated as a one-byte instruction. Fixes: e463a09af2f0 ("x86: Add straight-line-speculation mitigation") Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/167146051026.1374301.392728975473572291.stgit@devnote3
2022-12-27x86/calldepth: Fix incorrect init section referencesArnd Bergmann
The addition of callthunks_translate_call_dest means that skip_addr() and patch_dest() can no longer be discarded as part of the __init section freeing: WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> skip_addr (section: .init.text) WARNING: modpost: vmlinux.o: section mismatch in reference: callthunks_translate_call_dest.cold (section: .text.unlikely) -> patch_dest (section: .init.text) WARNING: modpost: vmlinux.o: section mismatch in reference: is_callthunk.cold (section: .text.unlikely) -> skip_addr (section: .init.text) ERROR: modpost: Section mismatches detected. Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them. Fixes: b2e9dfe54be4 ("x86/bpf: Emit call depth accounting if required") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20221215164334.968863-1-arnd@kernel.org
2022-12-27perf/core: Call LSM hook after copying perf_event_attrNamhyung Kim
It passes the attr struct to the security_perf_event_open() but it's not initialized yet. Fixes: da97e18458fb ("perf_event: Add support for LSM and SELinux checks") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20221220223140.4020470-1-namhyung@kernel.org
2022-12-27perf: Fix use-after-free in error pathPeter Zijlstra
The syscall error path has a use-after-free; put_pmu_ctx() will reference ctx, therefore we must ensure ctx is destroyed after pmu_ctx is. Fixes: bd2756811766 ("perf: Rewrite core context handling") Reported-by: syzbot+b8e8c01c8ade4fe6e48f@syzkaller.appspotmail.com Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Chengming Zhou <zhouchengming@bytedance.com> Link: https://lkml.kernel.org/r/Y6B3xEgkbmFUCeni@hirez.programming.kicks-ass.net
2022-12-27perf/x86/amd: fix potential integer overflow on shift of a intColin Ian King
The left shift of int 32 bit integer constant 1 is evaluated using 32 bit arithmetic and then passed as a 64 bit function argument. In the case where i is 32 or more this can lead to an overflow. Avoid this by shifting using the BIT_ULL macro instead. Fixes: 471af006a747 ("perf/x86/amd: Constrain Large Increment per Cycle events") Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ian Rogers <irogers@google.com> Acked-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/20221202135149.1797974-1-colin.i.king@gmail.com
2022-12-27perf/core: Fix cgroup events trackingChengming Zhou
We encounter perf warnings when using cgroup events like: cd /sys/fs/cgroup mkdir test perf stat -e cycles -a -G test Which then triggers: WARNING: CPU: 0 PID: 690 at kernel/events/core.c:849 perf_cgroup_switch+0xb2/0xc0 Call Trace: <TASK> __schedule+0x4ae/0x9f0 ? _raw_spin_unlock_irqrestore+0x23/0x40 ? __cond_resched+0x18/0x20 preempt_schedule_common+0x2d/0x70 __cond_resched+0x18/0x20 wait_for_completion+0x2f/0x160 ? cpu_stop_queue_work+0x9e/0x130 affine_move_task+0x18a/0x4f0 WARNING: CPU: 0 PID: 690 at kernel/events/core.c:829 ctx_sched_in+0x1cf/0x1e0 Call Trace: <TASK> ? ctx_sched_out+0xb7/0x1b0 perf_cgroup_switch+0x88/0xc0 __schedule+0x4ae/0x9f0 ? _raw_spin_unlock_irqrestore+0x23/0x40 ? __cond_resched+0x18/0x20 preempt_schedule_common+0x2d/0x70 __cond_resched+0x18/0x20 wait_for_completion+0x2f/0x160 ? cpu_stop_queue_work+0x9e/0x130 affine_move_task+0x18a/0x4f0 The above two warnings are not complete here since I remove other unimportant information. The problem is caused by the perf cgroup events tracking: CPU0 CPU1 perf_event_open() perf_event_alloc() account_event() account_event_cpu() atomic_inc(perf_cgroup_events) __perf_event_task_sched_out() if (atomic_read(perf_cgroup_events)) perf_cgroup_switch() // kernel/events/core.c:849 WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0) if (READ_ONCE(cpuctx->cgrp) == cgrp) // false return perf_ctx_lock() ctx_sched_out() cpuctx->cgrp = cgrp ctx_sched_in() perf_cgroup_set_timestamp() // kernel/events/core.c:829 WARN_ON_ONCE(!ctx->nr_cgroups) perf_ctx_unlock() perf_install_in_context() cpu_function_call() __perf_install_in_context() add_event_to_ctx() list_add_event() perf_cgroup_event_enable() ctx->nr_cgroups++ cpuctx->cgrp = X We can see from above that we wrongly use percpu atomic perf_cgroup_events to check if we need to perf_cgroup_switch(), which should only be used when we know this CPU has cgroup events enabled. The commit bd2756811766 ("perf: Rewrite core context handling") change to have only one context per-CPU, so we can just use cpuctx->cgrp to check if this CPU has cgroup events enabled. So percpu atomic perf_cgroup_events is not needed. Fixes: bd2756811766 ("perf: Rewrite core context handling") Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lkml.kernel.org/r/20221207124023.66252-1-zhouchengming@bytedance.com
2022-12-27perf core: Return error pointer if inherit_event() fails to find pmu_ctxRavi Bangoria
inherit_event() returns NULL only when it finds orphaned events otherwise it returns either valid child_event pointer or an error pointer. Follow the same when it fails to find pmu_ctx. Fixes: bd2756811766 ("perf: Rewrite core context handling") Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20221118051539.820-1-ravi.bangoria@amd.com
2022-12-27platform/x86: ideapad-laptop: Add Legion 5 15ARH05 DMI id to ↵Hans de Goede
set_fn_lock_led_list[] The Lenovo Legion 5 15ARH05 needs ideapad-laptop to call SALS_FNLOCK_ON / SALS_FNLOCK_OFF on Fn-lock state change to get the LED in the Fn key to correctly reflect the Fn-lock state. Add a DMI match for the Legion 5 15ARH05 to the set_fn_lock_led_list[] table for this. Fixes: 81a5603a0f50 ("platform/x86: ideapad-laptop: Fix interrupt storm on fn-lock toggle on some Yoga laptops") Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20221215154357.123876-1-hdegoede@redhat.com
2022-12-27platform/x86: sony-laptop: Don't turn off 0x153 keyboard backlight during probeHans de Goede
The 0x153 version of the kbd backlight control SNC handle has no separate address to probe if the backlight is there. This turns the probe call into a set keyboard backlight call with a value of 0 turning off the keyboard backlight. Skip probing when there is no separate probe address to avoid this. Link: https://bugzilla.redhat.com/show_bug.cgi?id=1583752 Fixes: 800f20170dcf ("Keyboard backlight control for some Vaio Fit models") Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mattia Dongili <malattia@linux.it> Link: https://lore.kernel.org/r/20221213122943.11123-1-hdegoede@redhat.com
2022-12-27KVM: x86/xen: Documentation updates and clarificationsDavid Woodhouse
Most notably, the KVM_XEN_EVTCHN_RESET feature had escaped documentation entirely. Along with how to turn most stuff off on SHUTDOWN_soft_reset. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20221226120320.1125390-6-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: x86/xen: Add KVM_XEN_INVALID_GPA and KVM_XEN_INVALID_GFN to uapiDavid Woodhouse
These are (uint64_t)-1 magic values are a userspace ABI, allowing the shared info pages and other enlightenments to be disabled. This isn't a Xen ABI because Xen doesn't let the guest turn these off except with the full SHUTDOWN_soft_reset mechanism. Under KVM, the userspace VMM is expected to handle soft reset, and tear down the kernel parts of the enlightenments accordingly. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20221226120320.1125390-5-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: x86/xen: Simplify eventfd IOCTLsMichal Luczaj
Port number is validated in kvm_xen_setattr_evtchn(). Remove superfluous checks in kvm_xen_eventfd_assign() and kvm_xen_eventfd_update(). Signed-off-by: Michal Luczaj <mhal@rbox.co> Message-Id: <20221222203021.1944101-3-mhal@rbox.co> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20221226120320.1125390-4-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: x86/xen: Fix SRCU/RCU usage in readers of evtchn_portsPaolo Bonzini
The evtchnfd structure itself must be protected by either kvm->lock or SRCU. Use the former in kvm_xen_eventfd_update(), since the lock is being taken anyway; kvm_xen_hcall_evtchn_send() instead is a reader and does not need kvm->lock, and is called in SRCU critical section from the kvm_x86_handle_exit function. It is also important to use rcu_read_{lock,unlock}() in kvm_xen_hcall_evtchn_send(), because idr_remove() will *not* use synchronize_srcu() to wait for readers to complete. Remove a superfluous if (kvm) check before calling synchronize_srcu() in kvm_xen_eventfd_deassign() where kvm has been dereferenced already. Co-developed-by: Michal Luczaj <mhal@rbox.co> Signed-off-by: Michal Luczaj <mhal@rbox.co> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20221226120320.1125390-3-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: x86/xen: Use kvm_read_guest_virt() instead of open-coding it badlyDavid Woodhouse
In particular, we shouldn't assume that being contiguous in guest virtual address space means being contiguous in guest *physical* address space. In dropping the manual calls to kvm_mmu_gva_to_gpa_system(), also drop the srcu_read_lock() that was around them. All call sites are reached from kvm_xen_hypercall() which is called from the handle_exit function with the read lock already held. 536395260 ("KVM: x86/xen: handle PV timers oneshot mode") 1a65105a5 ("KVM: x86/xen: handle PV spinlocks slowpath") Fixes: 2fd6df2f2 ("KVM: x86/xen: intercept EVTCHNOP_send from guests") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20221226120320.1125390-2-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: x86/xen: Fix memory leak in kvm_xen_write_hypercall_page()Michal Luczaj
Release page irrespectively of kvm_vcpu_write_guest() return value. Suggested-by: Paul Durrant <paul@xen.org> Fixes: 23200b7a30de ("KVM: x86/xen: intercept xen hypercalls if enabled") Signed-off-by: Michal Luczaj <mhal@rbox.co> Message-Id: <20221220151454.712165-1-mhal@rbox.co> Reviewed-by: Paul Durrant <paul@xen.org> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20221226120320.1125390-1-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: Delete extra block of "};" in the KVM API documentationSean Christopherson
Delete an extra block of code/documentation that snuck in when KVM's documentation was converted to ReST format. Fixes: 106ee47dc633 ("docs: kvm: Convert api.txt to ReST format") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221207003637.2041211-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27kvm: x86/mmu: Remove duplicated "be split" in spte.hLai Jiangshan
"be split be split" -> "be split" Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com> Message-Id: <20221207120505.9175-1-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27kvm: Remove the unused macro KVM_MMU_READ_{,UN}LOCK()Lai Jiangshan
No code is using KVM_MMU_READ_LOCK() or KVM_MMU_READ_UNLOCK(). They used to be in virt/kvm/pfncache.c: KVM_MMU_READ_LOCK(kvm); retry = mmu_notifier_retry_hva(kvm, mmu_seq, uhva); KVM_MMU_READ_UNLOCK(kvm); However, since 58cd407ca4c6 ("KVM: Fix multiple races in gfn=>pfn cache refresh", 2022-05-25) the code is only relying on the MMU notifier's invalidation count and sequence number. Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com> Message-Id: <20221207120617.9409-1-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27MAINTAINERS: adjust entry after renaming the vmx hyperv filesLukas Bulwahn
Commit a789aeba4196 ("KVM: VMX: Rename "vmx/evmcs.{ch}" to "vmx/hyperv.{ch}"") renames the VMX specific Hyper-V files, but does not adjust the entry in MAINTAINERS. Hence, ./scripts/get_maintainer.pl --self-test=patterns complains about a broken reference. Repair this file reference in KVM X86 HYPER-V (KVM/hyper-v). Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Fixes: a789aeba4196 ("KVM: VMX: Rename "vmx/evmcs.{ch}" to "vmx/hyperv.{ch}"") Reviewed-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221205082044.10141-1-lukas.bulwahn@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Mark correct page as mapped in virt_map()Oliver Upton
The loop marks vaddr as mapped after incrementing it by page size, thereby marking the *next* page as mapped. Set the bit in vpages_mapped first instead. Fixes: 56fc7732031d ("KVM: selftests: Fill in vm->vpages_mapped bitmap in virt_map() too") Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Message-Id: <20221209015307.1781352-4-oliver.upton@linux.dev> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: arm64: selftests: Don't identity map the ucall MMIO holeOliver Upton
Currently the ucall MMIO hole is placed immediately after slot0, which is a relatively safe address in the PA space. However, it is possible that the same address has already been used for something else (like the guest program image) in the VA space. At least in my own testing, building the vgic_irq test with clang leads to the MMIO hole appearing underneath gicv3_ops. Stop identity mapping the MMIO hole and instead find an unused VA to map to it. Yet another subtle detail of the KVM selftests library is that virt_pg_map() does not update vm->vpages_mapped. Switch over to virt_map() instead to guarantee that the chosen VA isn't to something else. Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Message-Id: <20221209015307.1781352-6-oliver.upton@linux.dev> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: document the default implementation of vm_vaddr_populate_bitmapPaolo Bonzini
Explain the meaning of the bit manipulations of vm_vaddr_populate_bitmap. These correspond to the "canonical addresses" of x86 and other architectures, but that is not obvious. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Use magic value to signal ucall_alloc() failureSean Christopherson
Use a magic value to signal a ucall_alloc() failure instead of simply doing GUEST_ASSERT(). GUEST_ASSERT() relies on ucall_alloc() and so a failure puts the guest into an infinite loop. Use -1 as the magic value, as a real ucall struct should never wrap. Reported-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Disable "gnu-variable-sized-type-not-at-end" warningSean Christopherson
Disable gnu-variable-sized-type-not-at-end so that tests and libraries can create overlays of variable sized arrays at the end of structs when using a fixed number of entries, e.g. to get/set a single MSR. It's possible to fudge around the warning, e.g. by defining a custom struct that hardcodes the number of entries, but that is a burden for both developers and readers of the code. lib/x86_64/processor.c:664:19: warning: field 'header' with variable sized type 'struct kvm_msrs' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_msrs header; ^ lib/x86_64/processor.c:772:19: warning: field 'header' with variable sized type 'struct kvm_msrs' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_msrs header; ^ lib/x86_64/processor.c:787:19: warning: field 'header' with variable sized type 'struct kvm_msrs' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_msrs header; ^ 3 warnings generated. x86_64/hyperv_tlb_flush.c:54:18: warning: field 'hv_vp_set' with variable sized type 'struct hv_vpset' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct hv_vpset hv_vp_set; ^ 1 warning generated. x86_64/xen_shinfo_test.c:137:25: warning: field 'info' with variable sized type 'struct kvm_irq_routing' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end] struct kvm_irq_routing info; ^ 1 warning generated. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-12-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Include lib.mk before consuming $(CC)Sean Christopherson
Include lib.mk before consuming $(CC) and document that lib.mk overwrites $(CC) unless make was invoked with -e or $(CC) was specified after make (which makes the environment override the Makefile). Including lib.mk after using it for probing, e.g. for -no-pie, can lead to weirdness. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-11-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Explicitly disable builtins for mem*() overridesSean Christopherson
Explicitly disable the compiler's builtin memcmp(), memcpy(), and memset(). Because only lib/string_override.c is built with -ffreestanding, the compiler reserves the right to do what it wants and can try to link the non-freestanding code to its own crud. /usr/bin/x86_64-linux-gnu-ld: /lib/x86_64-linux-gnu/libc.a(memcmp.o): in function `memcmp_ifunc': (.text+0x0): multiple definition of `memcmp'; tools/testing/selftests/kvm/lib/string_override.o: tools/testing/selftests/kvm/lib/string_override.c:15: first defined here clang: error: linker command failed with exit code 1 (use -v to see invocation) Fixes: 6b6f71484bf4 ("KVM: selftests: Implement memcmp(), memcpy(), and memset() for guest use") Reported-by: Aaron Lewis <aaronlewis@google.com> Reported-by: Raghavendra Rao Ananta <rananta@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-10-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Probe -no-pie with actual CFLAGS used to compileSean Christopherson
Probe -no-pie with the actual set of CFLAGS used to compile the tests, clang whines about -no-pie being unused if the tests are compiled with -static. clang: warning: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-9-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Use proper function prototypes in probing codeSean Christopherson
Make the main() functions in the probing code proper prototypes so that compiling the probing code with more strict flags won't generate false negatives. <stdin>:1:5: error: function declaration isn’t a prototype [-Werror=strict-prototypes] Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-8-seanjc@google.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Rename UNAME_M to ARCH_DIR, fill explicitly for x86Sean Christopherson
Rename UNAME_M to ARCH_DIR and explicitly set it directly for x86. At this point, the name of the arch directory really doesn't have anything to do with `uname -m`, and UNAME_M is unnecessarily confusing given that its purpose is purely to identify the arch specific directory. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-7-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Fix a typo in x86-64's kvm_get_cpu_address_width()Sean Christopherson
Fix a == vs. = typo in kvm_get_cpu_address_width() that results in @pa_bits being left unset if the CPU doesn't support enumerating its MAX_PHY_ADDR. Flagged by clang's unusued-value warning. lib/x86_64/processor.c:1034:51: warning: expression result unused [-Wunused-value] *pa_bits == kvm_cpu_has(X86_FEATURE_PAE) ? 36 : 32; Fixes: 3bd396353d18 ("KVM: selftests: Add X86_FEATURE_PAE and use it calc "fallback" MAXPHYADDR") Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Message-Id: <20221213001653.3852042-6-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Use pattern matching in .gitignoreSean Christopherson
Use pattern matching to exclude everything except .c, .h, .S, and .sh files from Git. Manually adding every test target has an absurd maintenance cost, is comically error prone, and leads to bikeshedding over whether or not the targets should be listed in alphabetical order. Deliberately do not include the one-off assets, e.g. config, settings, .gitignore itself, etc as Git doesn't ignore files that are already in the repository. Adding the one-off assets won't prevent mistakes where developers forget to --force add files that don't match the "allowed". Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Fix divide-by-zero bug in memslot_perf_testSean Christopherson
Check that the number of pages per slot is non-zero in get_max_slots() prior to computing the remaining number of pages. clang generates code that uses an actual DIV for calculating the remaining, which causes a #DE if the total number of pages is less than the number of slots. traps: memslot_perf_te[97611] trap divide error ip:4030c4 sp:7ffd18ae58f0 error:0 in memslot_perf_test[401000+cb000] Fixes: a69170c65acd ("KVM: selftests: memslot_perf_test: Report optimal memory slots") Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Message-Id: <20221213001653.3852042-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-27KVM: selftests: Delete dead code in x86_64/vmx_tsc_adjust_test.cSean Christopherson
Delete an unused struct definition in x86_64/vmx_tsc_adjust_test.c. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221213001653.3852042-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>