summaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2020-06-11media: atomisp: get rid of hmm_vm.cMauro Carvalho Chehab
This is not used anywhere. So, let's trash it. Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-06-11media: atomisp: fix pipeline initialization codeMauro Carvalho Chehab
The code under load_primary_binaries() is complex and were hard to understand, because it used to have lots of ifdefs and broken identation. The patch which cleaned it and removed the version-specific ifdefs added a regression. Solve it. Fixes: 3c0538fbad9f ("media: atomisp: get rid of most checks for ISP2401 version") Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-06-11io_uring: fix io_kiocb.flags modification race in IOPOLL modeXiaoguang Wang
While testing io_uring in arm, we found sometimes io_sq_thread() keeps polling io requests even though there are not inflight io requests in block layer. After some investigations, found a possible race about io_kiocb.flags, see below race codes: 1) in the end of io_write() or io_read() req->flags &= ~REQ_F_NEED_CLEANUP; kfree(iovec); return ret; 2) in io_complete_rw_iopoll() if (res != -EAGAIN) req->flags |= REQ_F_IOPOLL_COMPLETED; In IOPOLL mode, io requests still maybe completed by interrupt, then above codes are not safe, concurrent modifications to req->flags, which is not protected by lock or is not atomic modifications. I also had disassemble io_complete_rw_iopoll() in arm: req->flags |= REQ_F_IOPOLL_COMPLETED; 0xffff000008387b18 <+76>: ldr w0, [x19,#104] 0xffff000008387b1c <+80>: orr w0, w0, #0x1000 0xffff000008387b20 <+84>: str w0, [x19,#104] Seems that the "req->flags |= REQ_F_IOPOLL_COMPLETED;" is load and modification, two instructions, which obviously is not atomic. To fix this issue, add a new iopoll_completed in io_kiocb to indicate whether io request is completed. Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11KVM: nVMX: Consult only the "basic" exit reason when routing nested exitSean Christopherson
Consult only the basic exit reason, i.e. bits 15:0 of vmcs.EXIT_REASON, when determining whether a nested VM-Exit should be reflected into L1 or handled by KVM in L0. For better or worse, the switch statement in nested_vmx_exit_reflected() currently defaults to "true", i.e. reflects any nested VM-Exit without dedicated logic. Because the case statements only contain the basic exit reason, any VM-Exit with modifier bits set will be reflected to L1, even if KVM intended to handle it in L0. Practically speaking, this only affects EXIT_REASON_MCE_DURING_VMENTRY, i.e. a #MC that occurs on nested VM-Enter would be incorrectly routed to L1, as "failed VM-Entry" is the only modifier that KVM can currently encounter. The SMM modifiers will never be generated as KVM doesn't support/employ a SMI Transfer Monitor. Ditto for "exit from enclave", as KVM doesn't yet support virtualizing SGX, i.e. it's impossible to enter an enclave in a KVM guest (L1 or L2). Fixes: 644d711aa0e1 ("KVM: nVMX: Deciding if L0 or L1 should handle an L2 exit") Cc: Jim Mattson <jmattson@google.com> Cc: Xiaoyao Li <xiaoyao.li@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200227174430.26371-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-11umem: remove redundant initialization of variable retColin Ian King
The variable ret is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Signed-off-by: Colin Ian King <colin.king@canonical.com> Addresses-Coverity: ("Unused value") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11pktcdvd: remove redundant initialization of variable retColin Ian King
The variable ret is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Signed-off-by: Colin Ian King <colin.king@canonical.com> Addresses-Coverity: ("Unused value") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11nvmet: fail outstanding host posted AEN reqChaitanya Kulkarni
In function nvmet_async_event_process() we only process AENs iff there is an open slot on the ctrl->async_event_cmds[] && aen event list posted by the target is not empty. This keeps host posted AEN outstanding if target generated AEN list is empty. We do cleanup the target generated entries from the aen list in nvmet_ctrl_free()-> nvmet_async_events_free() but we don't process AEN posted by the host. This leads to following problem :- When processing admin sq at the time of nvmet_sq_destroy() holds an extra percpu reference(atomic value = 1), so in the following code path after switching to atomic rcu, release function (nvmet_sq_free()) is not getting called which blocks the sq->free_done in nvmet_sq_destroy() :- nvmet_sq_destroy() percpu_ref_kill_and_confirm() - __percpu_ref_switch_mode() -- __percpu_ref_switch_to_atomic() --- call_rcu() -> percpu_ref_switch_to_atomic_rcu() ---- /* calls switch callback */ - percpu_ref_put() -- percpu_ref_put_many(ref, 1) --- else if (unlikely(atomic_long_sub_and_test(nr, &ref->count))) ---- ref->release(ref); <---- Not called. This results in indefinite hang:- void nvmet_sq_destroy(struct nvmet_sq *sq) ... if (ctrl && ctrl->sqs && ctrl->sqs[0] == sq) { nvmet_async_events_process(ctrl, status); percpu_ref_put(&sq->ref); } percpu_ref_kill_and_confirm(&sq->ref, nvmet_confirm_sq); wait_for_completion(&sq->confirm_done); wait_for_completion(&sq->free_done); <-- Hang here Which breaks the further disconnect sequence. This problem seems to be introduced after commit 64f5e9cdd711b ("nvmet: fix memory leak when removing namespaces and controllers concurrently"). This patch processes ctrl->async_event_cmds[] in the admin sq destroy() context irrespetive of aen_list. Also we get rid of the controller's aen_list processing in the nvmet_sq_destroy() context and just ignore ctrl->aen_list. This results in nvmet_async_events_process() being called from workqueue context so we adjust the code accordingly. Fixes: 64f5e9cdd711 ("nvmet: fix memory leak when removing namespaces and controllers concurrently ") Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11nvme-pci: use simple suspend when a HMB is enabledChristoph Hellwig
While the NVMe specification allows the device to access the host memory buffer in host DRAM from all power states, hosts will fail access to DRAM during S3 and similar power states. Fixes: d916b1be94b6 ("nvme-pci: use host managed power state for suspend") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11nvme-fc: don't call nvme_cleanup_cmd() for AENsDaniel Wagner
Asynchronous event notifications do not have an associated request. When fcp_io() fails we unconditionally call nvme_cleanup_cmd() which leads to a crash. Fixes: 16686f3a6c3c ("nvme: move common call to nvme_cleanup_cmd to core layer") Signed-off-by: Daniel Wagner <dwagner@suse.de> Reviewed-by: Himanshu Madhani <hmadhani2024@gmail.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: James Smart <james.smart@broadcom.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11nvmet-tcp: constify nvmet_tcp_opsMax Gurtovoy
nvmet_tcp_ops is never modified and can be made const to allow the compiler to put it in read-only memory, as done in other transports. Before: text data bss dec hex filename 16164 160 12 16336 3fd0 drivers/nvme/target/tcp.o After: text data bss dec hex filename 16277 64 12 16353 3fe1 drivers/nvme/target/tcp.o Signed-off-by: Max Gurtovoy <maxg@mellanox.com> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Reviewed-by: Israel Rukshin <israelr@mellanox.com> Acked-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11nvme-tcp: constify nvme_tcp_mq_ops and nvme_tcp_admin_mq_opsRikard Falkeborn
nvme_tcp_mq_ops and nvme_tcp_admin_mq_ops are never modified and can be made const to allow the compiler to put them in read-only memory. Before: text data bss dec hex filename 53102 6885 576 60563 ec93 drivers/nvme/host/tcp.o After: text data bss dec hex filename 53422 6565 576 60563 ec93 drivers/nvme/host/tcp.o Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Acked-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11nvme: do not call del_gendisk() on a disk that was never addedNiklas Cassel
device_add_disk() is negated by del_gendisk(). alloc_disk_node() is negated by put_disk(). In nvme_alloc_ns(), device_add_disk() is one of the last things being called in the success case, and only void functions are being called after this. Therefore this call should not be negated in the error path. The superfluous call to del_gendisk() leads to the following prints: [ 7.839975] kobject: '(null)' (000000001ff73734): is not initialized, yet kobject_put() is being called. [ 7.840865] WARNING: CPU: 2 PID: 361 at lib/kobject.c:736 kobject_put+0x70/0x120 Fixes: 33cfdc2aa696 ("nvme: enforce extended LBA format for fabrics metadata") Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-11tools, bpftool: Fix memory leak in codegen error casesTobias Klauser
Free the memory allocated for the template on error paths in function codegen. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200610130804.21423-1-tklauser@distanz.ch
2020-06-11selftests/bpf: Add cgroup_skb/egress test for load_bytes_relativeYiFei Zhu
When cgroup_skb/egress triggers the MAC header is not set. Added a test that asserts reading MAC header is a -EFAULT but NET header succeeds. The test result from within the eBPF program is stored in an 1-element array map that the userspace then reads and asserts on. Another assertion is added that reading from a large offset, past the end of packet, returns -EFAULT. Signed-off-by: YiFei Zhu <zhuyifei@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/9028ccbea4385a620e69c0a104f469ffd655c01e.1591812755.git.zhuyifei@google.com
2020-06-11net/filter: Permit reading NET in load_bytes_relative when MAC not setYiFei Zhu
Added a check in the switch case on start_header that checks for the existence of the header, and in the case that MAC is not set and the caller requests for MAC, -EFAULT. If the caller requests for NET then MAC's existence is completely ignored. There is no function to check NET header's existence and as far as cgroup_skb/egress is concerned it should always be set. Removed for ptr >= the start of header, considering offset is bounded unsigned and should always be true. len <= end - mac is redundant to ptr + len <= end. Fixes: 3eee1f75f2b9 ("bpf: fix bpf_skb_load_bytes_relative pkt length check") Signed-off-by: YiFei Zhu <zhuyifei@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/76bb820ddb6a95f59a772ecbd8c8a336f646b362.1591812755.git.zhuyifei@google.com
2020-06-11x86/mce/dev-mcelog: Fix -Wstringop-truncation warning about strncpy()Tony Luck
The kbuild test robot reported this warning: arch/x86/kernel/cpu/mce/dev-mcelog.c: In function 'dev_mcelog_init_device': arch/x86/kernel/cpu/mce/dev-mcelog.c:346:2: warning: 'strncpy' output \ truncated before terminating nul copying 12 bytes from a string of the \ same length [-Wstringop-truncation] This is accurate, but I don't care that the trailing NUL character isn't copied. The string being copied is just a magic number signature so that crash dump tools can be sure they are decoding the right blob of memory. Use memcpy() instead of strncpy(). Fixes: d8ecca4043f2 ("x86/mce/dev-mcelog: Dynamically allocate space for machine check records") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200527182808.27737-1-tony.luck@intel.com
2020-06-11x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisonedTony Luck
An interesting thing happened when a guest Linux instance took a machine check. The VMM unmapped the bad page from guest physical space and passed the machine check to the guest. Linux took all the normal actions to offline the page from the process that was using it. But then guest Linux crashed because it said there was a second machine check inside the kernel with this stack trace: do_memory_failure set_mce_nospec set_memory_uc _set_memory_uc change_page_attr_set_clr cpa_flush clflush_cache_range_opt This was odd, because a CLFLUSH instruction shouldn't raise a machine check (it isn't consuming the data). Further investigation showed that the VMM had passed in another machine check because is appeared that the guest was accessing the bad page. Fix is to check the scope of the poison by checking the MCi_MISC register. If the entire page is affected, then unmap the page. If only part of the page is affected, then mark the page as uncacheable. This assumes that VMMs will do the logical thing and pass in the "whole page scope" via the MCi_MISC register (since they unmapped the entire page). [ bp: Adjust to x86/entry changes. ] Fixes: 284ce4011ba6 ("x86/memory_failure: Introduce {set, clear}_mce_nospec()") Reported-by: Jue Wang <juew@google.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jue Wang <juew@google.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200520163546.GA7977@agluck-desk2.amr.corp.intel.com
2020-06-11Merge branch 'x86/entry' into ras/coreThomas Gleixner
to fixup conflicts in arch/x86/kernel/cpu/mce/core.c so MCE specific follow up patches can be applied without creating a horrible merge conflict afterwards.
2020-06-11x86/entry: Unbreak __irqentry_text_start/end magicThomas Gleixner
The entry rework moved interrupt entry code from the irqentry to the noinstr section which made the irqentry section empty. This breaks boundary checks which rely on the __irqentry_text_start/end markers to find out whether a function in a stack trace is interrupt/exception entry code. This affects the function graph tracer and filter_irq_stacks(). As the IDT entry points are all sequentialy emitted this is rather simple to unbreak by injecting __irqentry_text_start/end as global labels. To make this work correctly: - Remove the IRQENTRY_TEXT section from the x86 linker script - Define __irqentry so it breaks the build if it's used - Adjust the entry mirroring in PTI - Remove the redundant kprobes and unwinder bound checks Reported-by: Qian Cai <cai@lca.pw> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-06-11x86/entry: __always_inline CR2 for noinstrPeter Zijlstra
vmlinux.o: warning: objtool: exc_page_fault()+0x9: call to read_cr2() leaves .noinstr.text section vmlinux.o: warning: objtool: exc_page_fault()+0x24: call to prefetchw() leaves .noinstr.text section vmlinux.o: warning: objtool: exc_page_fault()+0x21: call to kvm_handle_async_pf.isra.0() leaves .noinstr.text section vmlinux.o: warning: objtool: exc_nmi()+0x1cc: call to write_cr2() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200603114052.243227806@infradead.org
2020-06-11lockdep: __always_inline more for noinstrPeter Zijlstra
vmlinux.o: warning: objtool: debug_locks_off()+0xd: call to __debug_locks_off() leaves .noinstr.text section vmlinux.o: warning: objtool: match_held_lock()+0x6a: call to look_up_lock_class.isra.0() leaves .noinstr.text section vmlinux.o: warning: objtool: lock_is_held_type()+0x90: call to lockdep_recursion_finish() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200603114052.185201076@infradead.org
2020-06-11x86/entry: Re-order #DB handler to avoid *SAN instrumentationPeter Zijlstra
vmlinux.o: warning: objtool: exc_debug()+0xbb: call to clear_ti_thread_flag.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: noist_exc_debug()+0x55: call to clear_ti_thread_flag.constprop.0() leaves .noinstr.text section Rework things so that handle_debug() looses the noinstr and move the clear_thread_flag() into that. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200603114052.127756554@infradead.org
2020-06-11x86/entry: __always_inline arch_atomic_* for noinstrPeter Zijlstra
vmlinux.o: warning: objtool: rcu_dynticks_eqs_exit()+0x33: call to arch_atomic_and.constprop.0() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200603114052.070166551@infradead.org
2020-06-11x86/entry: __always_inline irqflags for noinstrPeter Zijlstra
vmlinux.o: warning: objtool: lockdep_hardirqs_on()+0x65: call to arch_local_save_flags() leaves .noinstr.text section vmlinux.o: warning: objtool: lockdep_hardirqs_off()+0x5d: call to arch_local_save_flags() leaves .noinstr.text section vmlinux.o: warning: objtool: lock_is_held_type()+0x35: call to arch_local_irq_save() leaves .noinstr.text section vmlinux.o: warning: objtool: check_preemption_disabled()+0x31: call to arch_local_save_flags() leaves .noinstr.text section vmlinux.o: warning: objtool: check_preemption_disabled()+0x33: call to arch_irqs_disabled_flags() leaves .noinstr.text section vmlinux.o: warning: objtool: lock_is_held_type()+0x2f: call to native_irq_disable() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200603114052.012171668@infradead.org
2020-06-11x86/entry: __always_inline debugreg for noinstrPeter Zijlstra
vmlinux.o: warning: objtool: exc_debug()+0x21: call to native_get_debugreg() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200603114051.954401211@infradead.org
2020-06-11x86/idt: Consolidate idt functionalityThomas Gleixner
- Move load_current_idt() out of line and replace the hideous comment with a lockdep assert. This allows to make idt_table and idt_descr static. - Mark idt_table read only after the IDT initialization is complete. - Shuffle code around to consolidate the #ifdef sections into one. - Adapt the F00F bug code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200528145523.084915381@linutronix.de
2020-06-11x86/idt: Cleanup trap_init()Thomas Gleixner
No point in having all the IDT cruft in trap_init(). Move it into the IDT code and fixup the comments. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200528145522.992376498@linutronix.de
2020-06-11x86/idt: Use proper constants for table sizeThomas Gleixner
Use the actual struct size to calculate the IDT table size instead of hardcoded values. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200528145522.898591501@linutronix.de
2020-06-11x86/idt: Add comments about early #PF handlingThomas Gleixner
The difference between 32 and 64 bit vs. early #PF handling is not documented. Replace the FIXME at idt_setup_early_pf() with proper comments. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200528145522.807135882@linutronix.de
2020-06-11x86/idt: Mark init only functions __initThomas Gleixner
Since 8175cfbbbfcb ("x86/idt: Remove update_intr_gate()") set_intr_gate() and idt_setup_from_table() are only called from __init functions. Mark them as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200528145522.715816477@linutronix.de
2020-06-11x86/entry: Rename trace_hardirqs_off_prepare()Peter Zijlstra
The typical pattern for trace_hardirqs_off_prepare() is: ENTRY lockdep_hardirqs_off(); // because hardware ... do entry magic instrumentation_begin(); trace_hardirqs_off_prepare(); ... do actual work trace_hardirqs_on_prepare(); lockdep_hardirqs_on_prepare(); instrumentation_end(); ... do exit magic lockdep_hardirqs_on(); which shows that it's named wrong, rename it to trace_hardirqs_off_finish(), as it concludes the hardirq_off transition. Also, given that the above is the only correct order, make the traditional all-in-one trace_hardirqs_off() follow suit. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.415774872@infradead.org
2020-06-11x86/entry: Clarify irq_{enter,exit}_rcu()Peter Zijlstra
Because: irq_enter_rcu() includes lockdep_hardirq_enter() irq_exit_rcu() does *NOT* include lockdep_hardirq_exit() Which resulted in two 'stray' lockdep_hardirq_exit() calls in idtentry.h, and me spending a long time trying to find the matching enter calls. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.359433429@infradead.org
2020-06-11x86/entry: Remove DBn stacksPeter Zijlstra
Both #DB itself, as all other IST users (NMI, #MC) now clear DR7 on entry. Combined with not allowing breakpoints on entry/noinstr/NOKPROBE text and no single step (EFLAGS.TF) inside the #DB handler should guarantee no nested #DB. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.303027161@infradead.org
2020-06-11x86/entry: Remove debug IDT frobbingPeter Zijlstra
This is all unused now. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.245019500@infradead.org
2020-06-11x86/entry: Optimize local_db_save() for virtPeter Zijlstra
Because DRn access is 'difficult' with virt; but the DR7 read is cheaper than a cacheline miss on native, add a virt specific fast path to local_db_save(), such that when breakpoints are not in use to avoid touching DRn entirely. Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.187833200@infradead.org
2020-06-11x86/entry, mce: Disallow #DB during #MCPeter Zijlstra
#MC is fragile as heck, don't tempt fate. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.131187767@infradead.org
2020-06-11x86/entry, nmi: Disable #DBPeter Zijlstra
Instead of playing stupid games with IST stacks, fully disallow #DB during NMIs. There is absolutely no reason to allow them, and killing this saves a heap of trouble. #DB is already forbidden on noinstr and CEA, so there can't be a #DB before this. Disabling it right after nmi_enter() ensures that the full NMI code is protected. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.069223695@infradead.org
2020-06-11x86/entry: Introduce local_db_{save,restore}()Peter Zijlstra
In order to allow other exceptions than #DB to disable breakpoints, provide common helpers. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.012060983@infradead.org
2020-06-11x86/hw_breakpoint: Prevent data breakpoints on user_pcid_flush_maskLai Jiangshan
The per-CPU user_pcid_flush_mask is used in the low level entry code. A data breakpoint can cause #DB recursion. Protect the full cpu_tlbstate structure for simplicity. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200526014221.2119-5-laijs@linux.alibaba.com Link: https://lkml.kernel.org/r/20200529213320.955117574@infradead.org
2020-06-11x86/hw_breakpoint: Prevent data breakpoints on per_cpu cpu_tss_rwLai Jiangshan
cpu_tss_rw is not directly referenced by hardware, but cpu_tss_rw is accessed in CPU entry code, especially when #DB shifts its stacks. If a data breakpoint would be set on cpu_tss_rw.x86_tss.ist[IST_INDEX_DB], it would cause recursive #DB ending up in a double fault. Add it to the list of protected items. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200526014221.2119-4-laijs@linux.alibaba.com Link: https://lkml.kernel.org/r/20200529213320.897976479@infradead.org
2020-06-11x86/hw_breakpoint: Prevent data breakpoints on direct GDTLai Jiangshan
A data breakpoint on the GDT can be fatal and must be avoided. The GDT in the CPU entry area is already protected, but not the direct GDT. Add the necessary protection. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200526014221.2119-3-laijs@linux.alibaba.com Link: https://lkml.kernel.org/r/20200529213320.840953950@infradead.org
2020-06-11x86/hw_breakpoint: Add within_area() to check data breakpointsLai Jiangshan
Add a within_area() helper to checking whether the data breakpoints overlap with cpu_entry_area. It will be used to completely prevent data breakpoints on GDT, IDT, or TSS. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200526014221.2119-2-laijs@linux.alibaba.com Link: https://lkml.kernel.org/r/20200529213320.784524504@infradead.org
2020-06-11xen: Move xen_setup_callback_vector() definition to include/xen/hvm.hVitaly Kuznetsov
Kbuild test robot reports the following problem on ARM: for 'xen_setup_callback_vector' [-Wmissing-prototypes] 1664 | void xen_setup_callback_vector(void) {} | ^~~~~~~~~~~~~~~~~~~~~~~~~ The problem is that xen_setup_callback_vector is a x86 only thing, its definition is present in arch/x86/xen/xen-ops.h but not on ARM. In events_base.c there is a stub for !CONFIG_XEN_PVHVM but it is not declared as 'static'. On x86 the situation is hardly better: drivers/xen/events/events_base.c doesn't include 'xen-ops.h' from arch/x86/xen/, it includes its namesake from include/xen/ which also results in a 'no previous prototype' warning. Currently, xen_setup_callback_vector() has two call sites: one in drivers/xen/events_base.c and another in arch/x86/xen/suspend_hvm.c. The former is placed under #ifdef CONFIG_X86 and the later is only compiled in when CONFIG_XEN_PVHVM. Resolve the issue by moving xen_setup_callback_vector() declaration to arch neutral 'include/xen/hvm.h' as the implementation lives in arch neutral drivers/xen/events/events_base.c. Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lkml.kernel.org/r/20200520161600.361895-1-vkuznets@redhat.com
2020-06-11x86/entry: Remove the TRACE_IRQS cruftThomas Gleixner
No more users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202120.523289762@linutronix.de
2020-06-11x86/entry: Move paranoid irq tracing out of ASM codeThomas Gleixner
The last step to remove the irq tracing cruft from ASM. Ignore #DF as the maschine is going to die anyway. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202120.414043330@linutronix.de
2020-06-11x86/entry/64: Remove TRACE_IRQS_*_DEBUGThomas Gleixner
Since INT3/#BP no longer runs on an IST, this workaround is no longer required. Tested by running lockdep+ftrace as described in the initial commit: 5963e317b1e9 ("ftrace/x86: Do not change stacks in DEBUG when calling lockdep") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202120.319418546@linutronix.de
2020-06-11x86/entry/32: Remove redundant irq disable codeThomas Gleixner
All exceptions/interrupts return with interrupts disabled now. No point in doing this in ASM again. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202120.221223450@linutronix.de
2020-06-11x86/entry: Make enter_from_user_mode() staticThomas Gleixner
The ASM users are gone. All callers are local. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202120.129232680@linutronix.de
2020-06-11x86/entry/64: Remove IRQ stack switching ASMThomas Gleixner
No more users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202120.021462159@linutronix.de
2020-06-11x86/entry: Remove the apic/BUILD interrupt leftoversThomas Gleixner
Remove all the code which was there to emit the system vector stubs. All users are gone. Move the now unused GET_CR2_INTO macro muck to head_64.S where the last user is. Fixup the eye hurting comment there while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202119.927433002@linutronix.de