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| * | blk-mq: order adding requests to hctx->dispatch and checking SCHED_RESTARTMing Lei2020-08-172-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SCHED_RESTART code path is relied to re-run queue for dispatch requests in hctx->dispatch. Meantime the SCHED_RSTART flag is checked when adding requests to hctx->dispatch. memory barriers have to be used for ordering the following two pair of OPs: 1) adding requests to hctx->dispatch and checking SCHED_RESTART in blk_mq_dispatch_rq_list() 2) clearing SCHED_RESTART and checking if there is request in hctx->dispatch in blk_mq_sched_restart(). Without the added memory barrier, either: 1) blk_mq_sched_restart() may miss requests added to hctx->dispatch meantime blk_mq_dispatch_rq_list() observes SCHED_RESTART, and not run queue in dispatch side or 2) blk_mq_dispatch_rq_list still sees SCHED_RESTART, and not run queue in dispatch side, meantime checking if there is request in hctx->dispatch from blk_mq_sched_restart() is missed. IO hang in ltp/fs_fill test is reported by kernel test robot: https://lkml.org/lkml/2020/7/26/77 Turns out it is caused by the above out-of-order OPs. And the IO hang can't be observed any more after applying this patch. Fixes: bd166ef183c2 ("blk-mq-sched: add framework for MQ capable IO schedulers") Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Christoph Hellwig <hch@lst.de> Cc: David Jeffery <djeffery@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | bsg-lib: convert comma to semicolonXu Wang2020-08-161-1/+1
| | | | | | | | | | | | | | | | | | | | | Replace a comma between expression statements by a semicolon. Signed-off-by: Xu Wang <vulab@iscas.ac.cn> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: blk-mq.c: fix @at_head kernel-doc warningRandy Dunlap2020-08-161-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a kernel-doc warning in block/blk-mq.c: ../block/blk-mq.c:1844: warning: Function parameter or member 'at_head' not described in 'blk_mq_request_bypass_insert' Fixes: 01e99aeca397 ("blk-mq: insert passthrough request into hctx->dispatch directly") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: André Almeida <andrealmeid@collabora.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Ming Lei <ming.lei@redhat.com> Cc: linux-block@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | Merge tag 'fallthrough-pseudo-keyword-5.9-rc3' of ↵Linus Torvalds2020-08-241148-2737/+2667
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux Pull 'fallthrough' keyword conversion from Gustavo A. R. Silva: "A tree-wide patch that replaces tons (2484) of /* fall through */ comments, and its variants, with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. There are currently 1167 intances of this fallthrough pseudo-keyword macro in mainline (5.9-rc2), that have been introduced over the last couple of development cycles: $ git grep -nw 'fallthrough;' | wc -l 1167 The global adoption of the fallthrough pseudo-keyword is something certain to happen; so, better sooner than later. :) This will also save everybody's time and thousands of lines of unnecessarily repetitive changelog text. After applying this patch on top of 5.9-rc2, we'll have a total of 3651 instances of this macro: $ git grep -nw 'fallthrough;' | wc -l 3651 This treewide patch doesn't address ALL fall-through markings in all subsystems at once because I have previously sent out patches for some of such subsystems separately, and I will follow up on them; however, this definitely contributes most of the work needed to replace all the fall-through markings with the fallthrough pseudo-keyword macro in the whole codebase. I have build-tested this patch on 10 different architectures: x86_64, i386, arm64, powerpc, s390, sparc64, sh, m68k, powerpc64 and alpha (allyesconfig for all of them). This is in linux-next already and kernel test robot has also helped me to successfully build-test early versions of this patch[2][3][4][5]" [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through [2] https://lore.kernel.org/lkml/5f3cc99a.HgvOW3rH0mD0RmkM%25lkp@intel.com/ [3] https://lore.kernel.org/lkml/5f3dd1d2.l1axczH+t4hMBZ63%25lkp@intel.com/ [4] https://lore.kernel.org/lkml/5f3e977a.mwYHUIObbR4SHr0B%25lkp@intel.com/ [5] https://lore.kernel.org/lkml/5f3f9e1c.qsyb%2FaySkiXNpkO4%25lkp@intel.com/ * tag 'fallthrough-pseudo-keyword-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: treewide: Use fallthrough pseudo-keyword
| * | | treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2020-08-231148-2737/+2667
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
* | | Linux 5.9-rc2v5.9-rc2Linus Torvalds2020-08-231-1/+1
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* | | Merge tag 'powerpc-5.9-3' of ↵Linus Torvalds2020-08-2321-25/+161
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Add perf support for emitting extended registers for power10. - A fix for CPU hotplug on pseries, where on large/loaded systems we may not wait long enough for the CPU to be offlined, leading to crashes. - Addition of a raw cputable entry for Power10, which is not required to boot, but is required to make our PMU setup work correctly in guests. - Three fixes for the recent changes on 32-bit Book3S to move modules into their own segment for strict RWX. - A fix for a recent change in our powernv PCI code that could lead to crashes. - A change to our perf interrupt accounting to avoid soft lockups when using some events, found by syzkaller. - A change in the way we handle power loss events from the hypervisor on pseries. We no longer immediately shut down if we're told we're running on a UPS. - A few other minor fixes. Thanks to Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju T Sudhakar, Athira Rajeev, Christophe Leroy, Frederic Barrat, Greg Kurz, Kajol Jain, Madhavan Srinivasan, Michael Neuling, Michael Roth, Nageswara R Sastry, Oliver O'Halloran, Thiago Jung Bauermann, Vaidyanathan Srinivasan, Vasant Hegde. * tag 'powerpc-5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/perf/hv-24x7: Move cpumask file to top folder of hv-24x7 driver powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000 powerpc/pseries: Do not initiate shutdown when system is running on UPS powerpc/perf: Fix soft lockups due to missed interrupt accounting powerpc/powernv/pci: Fix possible crash when releasing DMA resources powerpc/pseries/hotplug-cpu: wait indefinitely for vCPU death powerpc/32s: Fix is_module_segment() when MODULES_VADDR is defined powerpc/kasan: Fix KASAN_SHADOW_START on BOOK3S_32 powerpc/fixmap: Fix the size of the early debug area powerpc/pkeys: Fix build error with PPC_MEM_KEYS disabled powerpc/kernel: Cleanup machine check function declarations powerpc: Add POWER10 raw mode cputable entry powerpc/perf: Add extended regs support for power10 platform powerpc/perf: Add support for outputting extended regs in perf intr_regs powerpc: Fix P10 PVR revision in /proc/cpuinfo for SMT4 cores
| * | | powerpc/perf/hv-24x7: Move cpumask file to top folder of hv-24x7 driverKajol Jain2020-08-212-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 792f73f747b8 ("powerpc/hv-24x7: Add sysfs files inside hv-24x7 device to show cpumask") added cpumask file as part of hv-24x7 driver inside the interface folder. The cpumask file is supposed to be in the top folder of the PMU driver in order to make hotplug work. This patch fixes that issue and creates new group 'cpumask_attr_group' to add cpumask file and make sure it added in top folder. command:# cat /sys/devices/hv_24x7/cpumask 0 Fixes: 792f73f747b8 ("powerpc/hv-24x7: Add sysfs files inside hv-24x7 device to show cpumask") Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200821080610.123997-1-kjain@linux.ibm.com
| * | | powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000Christophe Leroy2020-08-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In is_module_segment(), when VMALLOC_END is over 0xf0000000, ALIGN(VMALLOC_END, SZ_256M) has value 0. In that case, addr >= ALIGN(VMALLOC_END, SZ_256M) is always true then is_module_segment() always returns false. Use (ALIGN(VMALLOC_END, SZ_256M) - 1) which will have value 0xffffffff and will be suitable for the comparison. Fixes: c49643319715 ("powerpc/32s: Only leave NX unset on segments used for modules") Reported-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/09fc73fe9c7423c6b4cf93f93df9bb0ed8eefab5.1597994047.git.christophe.leroy@csgroup.eu
| * | | powerpc/pseries: Do not initiate shutdown when system is running on UPSVasant Hegde2020-08-201-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As per PAPR we have to look for both EPOW sensor value and event modifier to identify the type of event and take appropriate action. In LoPAPR v1.1 section 10.2.2 includes table 136 "EPOW Action Codes": SYSTEM_SHUTDOWN 3 The system must be shut down. An EPOW-aware OS logs the EPOW error log information, then schedules the system to be shut down to begin after an OS defined delay internal (default is 10 minutes.) Then in section 10.3.2.2.8 there is table 146 "Platform Event Log Format, Version 6, EPOW Section", which includes the "EPOW Event Modifier": For EPOW sensor value = 3 0x01 = Normal system shutdown with no additional delay 0x02 = Loss of utility power, system is running on UPS/Battery 0x03 = Loss of system critical functions, system should be shutdown 0x04 = Ambient temperature too high All other values = reserved We have a user space tool (rtas_errd) on LPAR to monitor for EPOW_SHUTDOWN_ON_UPS. Once it gets an event it initiates shutdown after predefined time. It also starts monitoring for any new EPOW events. If it receives "Power restored" event before predefined time it will cancel the shutdown. Otherwise after predefined time it will shutdown the system. Commit 79872e35469b ("powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown") changed our handling of the "on UPS/Battery" case, to immediately shutdown the system. This breaks existing setups that rely on the userspace tool to delay shutdown and let the system run on the UPS. Fixes: 79872e35469b ("powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown") Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> [mpe: Massage change log and add PAPR references] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200820061844.306460-1-hegdevasant@linux.vnet.ibm.com
| * | | powerpc/perf: Fix soft lockups due to missed interrupt accountingAthira Rajeev2020-08-201-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Performance monitor interrupt handler checks if any counter has overflown and calls record_and_restart() in core-book3s which invokes perf_event_overflow() to record the sample information. Apart from creating sample, perf_event_overflow() also does the interrupt and period checks via perf_event_account_interrupt(). Currently we record information only if the SIAR (Sampled Instruction Address Register) valid bit is set (using siar_valid() check) and hence the interrupt check. But it is possible that we do sampling for some events that are not generating valid SIAR, and hence there is no chance to disable the event if interrupts are more than max_samples_per_tick. This leads to soft lockup. Fix this by adding perf_event_account_interrupt() in the invalid SIAR code path for a sampling event. ie if SIAR is invalid, just do interrupt check and don't record the sample information. Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1596717992-7321-1-git-send-email-atrajeev@linux.vnet.ibm.com
| * | | powerpc/powernv/pci: Fix possible crash when releasing DMA resourcesFrederic Barrat2020-08-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a typo introduced during recent code cleanup, which could lead to silently not freeing resources or an oops message (on PCI hotplug or CAPI reset). Only impacts ioda2, the code path for ioda1 is correct. Fixes: 01e12629af4e ("powerpc/powernv/pci: Add explicit tracking of the DMA setup state") Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Reviewed-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200819130741.16769-1-fbarrat@linux.ibm.com
| * | | powerpc/pseries/hotplug-cpu: wait indefinitely for vCPU deathMichael Roth2020-08-181-6/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For a power9 KVM guest with XIVE enabled, running a test loop where we hotplug 384 vcpus and then unplug them, the following traces can be seen (generally within a few loops) either from the unplugged vcpu: cpu 65 (hwid 65) Ready to die... Querying DEAD? cpu 66 (66) shows 2 list_del corruption. next->prev should be c00a000002470208, but was c00a000002470048 ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:56! Oops: Exception in kernel mode, sig: 5 [#1] LE SMP NR_CPUS=2048 NUMA pSeries Modules linked in: fuse nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 ... CPU: 66 PID: 0 Comm: swapper/66 Kdump: loaded Not tainted 4.18.0-221.el8.ppc64le #1 NIP: c0000000007ab50c LR: c0000000007ab508 CTR: 00000000000003ac REGS: c0000009e5a17840 TRAP: 0700 Not tainted (4.18.0-221.el8.ppc64le) MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 28000842 XER: 20040000 ... NIP __list_del_entry_valid+0xac/0x100 LR __list_del_entry_valid+0xa8/0x100 Call Trace: __list_del_entry_valid+0xa8/0x100 (unreliable) free_pcppages_bulk+0x1f8/0x940 free_unref_page+0xd0/0x100 xive_spapr_cleanup_queue+0x148/0x1b0 xive_teardown_cpu+0x1bc/0x240 pseries_mach_cpu_die+0x78/0x2f0 cpu_die+0x48/0x70 arch_cpu_idle_dead+0x20/0x40 do_idle+0x2f4/0x4c0 cpu_startup_entry+0x38/0x40 start_secondary+0x7bc/0x8f0 start_secondary_prolog+0x10/0x14 or on the worker thread handling the unplug: pseries-hotplug-cpu: Attempting to remove CPU <NULL>, drc index: 1000013a Querying DEAD? cpu 314 (314) shows 2 BUG: Bad page state in process kworker/u768:3 pfn:95de1 cpu 314 (hwid 314) Ready to die... page:c00a000002577840 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 flags: 0x5ffffc00000000() raw: 005ffffc00000000 5deadbeef0000100 5deadbeef0000200 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffff7f 0000000000000000 page dumped because: nonzero mapcount Modules linked in: kvm xt_CHECKSUM ipt_MASQUERADE xt_conntrack ... CPU: 0 PID: 548 Comm: kworker/u768:3 Kdump: loaded Not tainted 4.18.0-224.el8.bz1856588.ppc64le #1 Workqueue: pseries hotplug workque pseries_hp_work_fn Call Trace: dump_stack+0xb0/0xf4 (unreliable) bad_page+0x12c/0x1b0 free_pcppages_bulk+0x5bc/0x940 page_alloc_cpu_dead+0x118/0x120 cpuhp_invoke_callback.constprop.5+0xb8/0x760 _cpu_down+0x188/0x340 cpu_down+0x5c/0xa0 cpu_subsys_offline+0x24/0x40 device_offline+0xf0/0x130 dlpar_offline_cpu+0x1c4/0x2a0 dlpar_cpu_remove+0xb8/0x190 dlpar_cpu_remove_by_index+0x12c/0x150 dlpar_cpu+0x94/0x800 pseries_hp_work_fn+0x128/0x1e0 process_one_work+0x304/0x5d0 worker_thread+0xcc/0x7a0 kthread+0x1ac/0x1c0 ret_from_kernel_thread+0x5c/0x80 The latter trace is due to the following sequence: page_alloc_cpu_dead drain_pages drain_pages_zone free_pcppages_bulk where drain_pages() in this case is called under the assumption that the unplugged cpu is no longer executing. To ensure that is the case, and early call is made to __cpu_die()->pseries_cpu_die(), which runs a loop that waits for the cpu to reach a halted state by polling its status via query-cpu-stopped-state RTAS calls. It only polls for 25 iterations before giving up, however, and in the trace above this results in the following being printed only .1 seconds after the hotplug worker thread begins processing the unplug request: pseries-hotplug-cpu: Attempting to remove CPU <NULL>, drc index: 1000013a Querying DEAD? cpu 314 (314) shows 2 At that point the worker thread assumes the unplugged CPU is in some unknown/dead state and procedes with the cleanup, causing the race with the XIVE cleanup code executed by the unplugged CPU. Fix this by waiting indefinitely, but also making an effort to avoid spurious lockup messages by allowing for rescheduling after polling the CPU status and printing a warning if we wait for longer than 120s. Fixes: eac1e731b59ee ("powerpc/xive: guest exploitation of the XIVE interrupt controller") Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Tested-by: Greg Kurz <groug@kaod.org> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Reviewed-by: Greg Kurz <groug@kaod.org> [mpe: Trim oopses in change log slightly for readability] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200811161544.10513-1-mdroth@linux.vnet.ibm.com
| * | | powerpc/32s: Fix is_module_segment() when MODULES_VADDR is definedChristophe Leroy2020-08-181-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When MODULES_VADDR is defined, is_module_segment() shall check the address against it instead of checking agains VMALLOC_START. Fixes: 6ca055322da8 ("powerpc/32s: Use dedicated segment for modules with STRICT_KERNEL_RWX") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/07884ed033c31e074747b7eb8eaa329d15db07ec.1596641219.git.christophe.leroy@csgroup.eu
| * | | powerpc/kasan: Fix KASAN_SHADOW_START on BOOK3S_32Christophe Leroy2020-08-181-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On BOOK3S_32, when we have modules and strict kernel RWX, modules are not in vmalloc space but in a dedicated segment that is below PAGE_OFFSET. So KASAN_SHADOW_START must take it into account. MODULES_VADDR can't be used because it is not defined yet in kasan.h Fixes: 6ca055322da8 ("powerpc/32s: Use dedicated segment for modules with STRICT_KERNEL_RWX") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/6eddca2d5611fd57312a88eae31278c87a8fc99d.1596641224.git.christophe.leroy@csgroup.eu
| * | | powerpc/fixmap: Fix the size of the early debug areaChristophe Leroy2020-08-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ("03fd42d458fb powerpc/fixmap: Fix FIX_EARLY_DEBUG_BASE when page size is 256k") reworked the setup of the early debug area and mistakenly replaced 128 * 1024 by SZ_128. Change to SZ_128K to restore the original 128 kbytes size of the area. Fixes: 03fd42d458fb ("powerpc/fixmap: Fix FIX_EARLY_DEBUG_BASE when page size is 256k") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/996184974d674ff984643778cf1cdd7fe58cc065.1597644194.git.christophe.leroy@csgroup.eu
| * | | powerpc/pkeys: Fix build error with PPC_MEM_KEYS disabledAneesh Kumar K.V2020-08-171-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | IS_ENABLED() instead of #ifdef still requires variable declaration. In this specific case, default_uamor is declared in asm/pkeys.h which is only included if PPC_MEM_KEYS is enabled. arch/powerpc/mm/book3s64/hash_utils.c: In function ‘hash__early_init_mmu_secondary’: arch/powerpc/mm/book3s64/hash_utils.c:1119:21: error: ‘default_uamor’ undeclared (first use in this function) 1119 | mtspr(SPRN_UAMOR, default_uamor); | ^~~~~~~~~~~~~ Fixes: 6553fb799f60 ("powerpc/pkeys: Fix boot failures with Nemo board (A-EON AmigaOne X1000)") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200817103301.158836-1-aneesh.kumar@linux.ibm.com
| * | | powerpc/kernel: Cleanup machine check function declarationsMadhavan Srinivasan2020-08-174-8/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __machine_check_early_realmode_p*() are currently declared as extern in cputable.c and because of this when compiled with "C=1" (which enables semantic checker) produces these warnings. CHECK arch/powerpc/kernel/mce_power.c arch/powerpc/kernel/mce_power.c:709:6: warning: symbol '__machine_check_early_realmode_p7' was not declared. Should it be static? arch/powerpc/kernel/mce_power.c:717:6: warning: symbol '__machine_check_early_realmode_p8' was not declared. Should it be static? arch/powerpc/kernel/mce_power.c:722:6: warning: symbol '__machine_check_early_realmode_p9' was not declared. Should it be static? arch/powerpc/kernel/mce_power.c:740:6: warning: symbol '__machine_check_early_realmode_p10' was not declared. Should it be static? Patch here moves the declaration to asm/mce.h and includes the same in cputable.c Fixes: ae744f3432d3 ("powerpc/book3s: Flush SLB/TLBs if we get SLB/TLB machine check errors on power8") Fixes: 7b9f71f974a1 ("powerpc/64s: POWER9 machine check handler") Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200817005618.3305028-1-maddy@linux.ibm.com
| * | | powerpc: Add POWER10 raw mode cputable entryMadhavan Srinivasan2020-08-171-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a raw mode cputable entry for POWER10. Copies most of the fields from commit a3ea40d5c736 ("powerpc: Add POWER10 architected mode") except for oprofile_cpu_type, machine_check_early, pvr_mask and pvr_mask fields. On bare metal systems we use DT CPU features, which doesn't need a cputable entry. But in VMs we still rely on the raw cputable entry to set the correct values for the PMU related fields. Fixes: a3ea40d5c736 ("powerpc: Add POWER10 architected mode") Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> [mpe: Reorder vs cleanup patch and add Fixes tag] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200817005618.3305028-2-maddy@linux.ibm.com
| * | | powerpc/perf: Add extended regs support for power10 platformAthira Rajeev2020-08-173-1/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Include capability flag PERF_PMU_CAP_EXTENDED_REGS for power10 and expose MMCR3, SIER2, SIER3 registers as part of extended regs. Also introduce PERF_REG_PMU_MASK_31 to define extended mask value at runtime for power10. Suggested-by: Ryan Grimm <grimm@linux.ibm.com> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Tested-by: Nageswara R Sastry <nasastry@in.ibm.com> Reviewed-by: Kajol Jain <kjain@linux.ibm.com> Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1596794701-23530-3-git-send-email-atrajeev@linux.vnet.ibm.com
| * | | powerpc/perf: Add support for outputting extended regs in perf intr_regsAnju T Sudhakar2020-08-176-4/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for perf extended register capability in powerpc. The capability flag PERF_PMU_CAP_EXTENDED_REGS, is used to indicate the PMU which support extended registers. The generic code define the mask of extended registers as 0 for non supported architectures. Patch adds extended regs support for power9 platform by exposing MMCR0, MMCR1 and MMCR2 registers. REG_RESERVED mask needs update to include extended regs. PERF_REG_EXTENDED_MASK, contains mask value of the supported registers, is defined at runtime in the kernel based on platform since the supported registers may differ from one processor version to another and hence the MASK value. With the patch: available registers: r0 r1 r2 r3 r4 r5 r6 r7 r8 r9 r10 r11 r12 r13 r14 r15 r16 r17 r18 r19 r20 r21 r22 r23 r24 r25 r26 r27 r28 r29 r30 r31 nip msr orig_r3 ctr link xer ccr softe trap dar dsisr sier mmcra mmcr0 mmcr1 mmcr2 PERF_RECORD_SAMPLE(IP, 0x1): 4784/4784: 0 period: 1 addr: 0 ... intr regs: mask 0xffffffffffff ABI 64-bit .... r0 0xc00000000012b77c .... r1 0xc000003fe5e03930 .... r2 0xc000000001b0e000 .... r3 0xc000003fdcddf800 .... r4 0xc000003fc7880000 .... r5 0x9c422724be .... r6 0xc000003fe5e03908 .... r7 0xffffff63bddc8706 .... r8 0x9e4 .... r9 0x0 .... r10 0x1 .... r11 0x0 .... r12 0xc0000000001299c0 .... r13 0xc000003ffffc4800 .... r14 0x0 .... r15 0x7fffdd8b8b00 .... r16 0x0 .... r17 0x7fffdd8be6b8 .... r18 0x7e7076607730 .... r19 0x2f .... r20 0xc00000001fc26c68 .... r21 0xc0002041e4227e00 .... r22 0xc00000002018fb60 .... r23 0x1 .... r24 0xc000003ffec4d900 .... r25 0x80000000 .... r26 0x0 .... r27 0x1 .... r28 0x1 .... r29 0xc000000001be1260 .... r30 0x6008010 .... r31 0xc000003ffebb7218 .... nip 0xc00000000012b910 .... msr 0x9000000000009033 .... orig_r3 0xc00000000012b86c .... ctr 0xc0000000001299c0 .... link 0xc00000000012b77c .... xer 0x0 .... ccr 0x28002222 .... softe 0x1 .... trap 0xf00 .... dar 0x0 .... dsisr 0x80000000000 .... sier 0x0 .... mmcra 0x80000000000 .... mmcr0 0x82008090 .... mmcr1 0x1e000000 .... mmcr2 0x0 ... thread: perf:4784 Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Tested-by: Nageswara R Sastry <nasastry@in.ibm.com> Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Reviewed-by: Kajol Jain <kjain@linux.ibm.com> Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1596794701-23530-2-git-send-email-atrajeev@linux.vnet.ibm.com
| * | | powerpc: Fix P10 PVR revision in /proc/cpuinfo for SMT4 coresMichael Neuling2020-08-171-0/+1
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On POWER10 bit 12 in the PVR indicates if the core is SMT4 or SMT8. Bit 12 is set for SMT4. Without this patch, /proc/cpuinfo on a SMT4 DD1 POWER10 looks like this: cpu : POWER10, altivec supported revision : 17.0 (pvr 0080 1100) Fixes: a3ea40d5c736 ("powerpc: Add POWER10 architected mode") Cc: stable@vger.kernel.org # v5.8 Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200803035600.1820371-1-mikey@neuling.org
* | | Merge tag 'x86-urgent-2020-08-23' of ↵Linus Torvalds2020-08-231-4/+6
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fix from Thomas Gleixner: "A single fix for x86 which removes the RDPID usage from the paranoid entry path and unconditionally uses LSL to retrieve the CPU number. RDPID depends on MSR_TSX_AUX. KVM has an optmization to avoid expensive MRS read/writes on VMENTER/EXIT. It caches the MSR values and restores them either when leaving the run loop, on preemption or when going out to user space. MSR_TSX_AUX is part of that lazy MSR set, so after writing the guest value and before the lazy restore any exception using the paranoid entry will read the guest value and use it as CPU number to retrieve the GSBASE value for the current CPU when FSGSBASE is enabled. As RDPID is only used in that particular entry path, there is no reason to burden VMENTER/EXIT with two extra MSR writes. Remove the RDPID optimization, which is not even backed by numbers from the paranoid entry path instead" * tag 'x86-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry/64: Do not use RDPID in paranoid entry to accomodate KVM
| * | | x86/entry/64: Do not use RDPID in paranoid entry to accomodate KVMSean Christopherson2020-08-211-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM has an optmization to avoid expensive MRS read/writes on VMENTER/EXIT. It caches the MSR values and restores them either when leaving the run loop, on preemption or when going out to user space. The affected MSRs are not required for kernel context operations. This changed with the recently introduced mechanism to handle FSGSBASE in the paranoid entry code which has to retrieve the kernel GSBASE value by accessing per CPU memory. The mechanism needs to retrieve the CPU number and uses either LSL or RDPID if the processor supports it. Unfortunately RDPID uses MSR_TSC_AUX which is in the list of cached and lazily restored MSRs, which means between the point where the guest value is written and the point of restore, MSR_TSC_AUX contains a random number. If an NMI or any other exception which uses the paranoid entry path happens in such a context, then RDPID returns the random guest MSR_TSC_AUX value. As a consequence this reads from the wrong memory location to retrieve the kernel GSBASE value. Kernel GS is used to for all regular this_cpu_*() operations. If the GSBASE in the exception handler points to the per CPU memory of a different CPU then this has the obvious consequences of data corruption and crashes. As the paranoid entry path is the only place which accesses MSR_TSX_AUX (via RDPID) and the fallback via LSL is not significantly slower, remove the RDPID alternative from the entry path and always use LSL. The alternative would be to write MSR_TSC_AUX on every VMENTER and VMEXIT which would be inflicting massive overhead on that code path. [ tglx: Rewrote changelog ] Fixes: eaad981291ee3 ("x86/entry/64: Introduce the FIND_PERCPU_BASE macro") Reported-by: Tom Lendacky <thomas.lendacky@amd.com> Debugged-by: Tom Lendacky <thomas.lendacky@amd.com> Suggested-by: Andy Lutomirski <luto@kernel.org> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20200821105229.18938-1-pbonzini@redhat.com
* | | | Merge tag 'perf-urgent-2020-08-23' of ↵Linus Torvalds2020-08-231-3/+49
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 perf fix from Thomas Gleixner: "A single update for perf on x86 which has support for the broken down bandwith counters" * tag 'perf-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/uncore: Add BW counters for GT, IA and IO breakdown
| * | | | perf/x86/intel/uncore: Add BW counters for GT, IA and IO breakdownVaibhav Shankar2020-08-151-3/+49
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linux only has support to read total DDR reads and writes. Here we add support to enable bandwidth breakdown-GT, IA and IO. Breakdown of BW is important to debug and optimize memory access. This can also be used for telemetry and improving the system software.The offsets for GT, IA and IO are added and these free running counters can be accessed via MMIO space. The BW breakdown can be measured using the following cmd: perf stat -e uncore_imc/gt_requests/,uncore_imc/ia_requests/,uncore_imc/io_requests/ 30.57 MiB uncore_imc/gt_requests/ 1346.13 MiB uncore_imc/ia_requests/ 190.97 MiB uncore_imc/io_requests/ 5.984572733 seconds time elapsed BW/s = <gt,ia,io>_requests/time elapsed Signed-off-by: Vaibhav Shankar <vaibhav.shankar@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200814022234.23605-1-vaibhav.shankar@intel.com
* | | | Merge tag 'efi-urgent-2020-08-23' of ↵Linus Torvalds2020-08-237-92/+52
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fixes from Thomas Gleixner: - Enforce NX on RO data in mixed EFI mode - Destroy workqueue in an error handling path to prevent UAF - Stop argument parser at '--' which is the delimiter for init - Treat a NULL command line pointer as empty instead of dereferncing it unconditionally. - Handle an unterminated command line correctly - Cleanup the 32bit code leftovers and remove obsolete documentation * tag 'efi-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Documentation: efi: remove description of efi=old_map efi/x86: Move 32-bit code into efi_32.c efi/libstub: Handle unterminated cmdline efi/libstub: Handle NULL cmdline efi/libstub: Stop parsing arguments at "--" efi: add missed destroy_workqueue when efisubsys_init fails efi/x86: Mark kernel rodata non-executable for mixed mode
| * | | | Documentation: efi: remove description of efi=old_mapArd Biesheuvel2020-08-201-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The old EFI runtime region mapping logic that was kept around for some time has finally been removed entirely, along with the SGI UV1 support code that was its last remaining user. So remove any mention of the efi=old_map command line parameter from the docs. Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| * | | | efi/x86: Move 32-bit code into efi_32.cArd Biesheuvel2020-08-203-86/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the old memmap code has been removed, some code that was left behind in arch/x86/platform/efi/efi.c is only used for 32-bit builds, which means it can live in efi_32.c as well. So move it over. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| * | | | efi/libstub: Handle unterminated cmdlineArvind Sankar2020-08-201-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the command line parsing more robust, by handling the case it is not NUL-terminated. Use strnlen instead of strlen, and make sure that the temporary copy is NUL-terminated before parsing. Cc: <stable@vger.kernel.org> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200813185811.554051-4-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| * | | | efi/libstub: Handle NULL cmdlineArvind Sankar2020-08-201-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Treat a NULL cmdline the same as empty. Although this is unlikely to happen in practice, the x86 kernel entry does check for NULL cmdline and handles it, so do it here as well. Cc: <stable@vger.kernel.org> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200729193300.598448-1-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| * | | | efi/libstub: Stop parsing arguments at "--"Arvind Sankar2020-08-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Arguments after "--" are arguments for init, not for the kernel. Cc: <stable@vger.kernel.org> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200725155916.1376773-1-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| * | | | efi: add missed destroy_workqueue when efisubsys_init failsLi Heng2020-08-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | destroy_workqueue() should be called to destroy efi_rts_wq when efisubsys_init() init resources fails. Cc: <stable@vger.kernel.org> Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Li Heng <liheng40@huawei.com> Link: https://lore.kernel.org/r/1595229738-10087-1-git-send-email-liheng40@huawei.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| * | | | efi/x86: Mark kernel rodata non-executable for mixed modeArvind Sankar2020-08-201-0/+2
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When remapping the kernel rodata section RO in the EFI pagetables, the protection flags that were used for the text section are being reused, but the rodata section should not be marked executable. Cc: <stable@vger.kernel.org> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200717194526.3452089-1-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
* | | | Merge tag 'core-urgent-2020-08-23' of ↵Linus Torvalds2020-08-231-1/+2
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull entry fix from Thomas Gleixner: "A single bug fix for the common entry code. The transcription of the x86 version messed up the reload of the syscall number from pt_regs after ptrace and seccomp which breaks syscall number rewriting" * tag 'core-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: core/entry: Respect syscall number rewrites
| * | | | core/entry: Respect syscall number rewritesThomas Gleixner2020-08-211-1/+2
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The transcript of the x86 entry code to the generic version failed to reload the syscall number from ptregs after ptrace and seccomp have run, which both can modify the syscall number in ptregs. It returns the original syscall number instead which is obviously not the right thing to do. Reload the syscall number to fix that. Fixes: 142781e108b1 ("entry: Provide generic syscall entry functionality") Reported-by: Kyle Huey <me@kylehuey.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Tested-by: Kees Cook <keescook@chromium.org> Acked-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/87blj6ifo8.fsf@nanos.tec.linutronix.de
* | | | Merge tag 'edac_urgent_for_v5.9_rc2' of ↵Linus Torvalds2020-08-234-7/+7
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras Pull EDAC fix from Borislav Petkov: "A single fix correcting a reversed error severity determination check which lead to a recoverable error getting marked as fatal, by Tony Luck" * tag 'edac_urgent_for_v5.9_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras: EDAC/{i7core,sb,pnd2,skx}: Fix error event severity
| * | | | EDAC/{i7core,sb,pnd2,skx}: Fix error event severityTony Luck2020-08-184-7/+7
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | IA32_MCG_STATUS.RIPV indicates whether the return RIP value pushed onto the stack as part of machine check delivery is valid or not. Various drivers copied a code fragment that uses the RIPV bit to determine the severity of the error as either HW_EVENT_ERR_UNCORRECTED or HW_EVENT_ERR_FATAL, but this check is reversed (marking errors where RIPV is set as "FATAL"). Reverse the tests so that the error is marked fatal when RIPV is not set. Reported-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200707194324.14884-1-tony.luck@intel.com
* | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds2020-08-2344-163/+310
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: "Nothing earth shattering here, lots of small fixes (f.e. missing RCU protection, bad ref counting, missing memset(), etc.) all over the place: 1) Use get_file_rcu() in task_file iterator, from Yonghong Song. 2) There are two ways to set remote source MAC addresses in macvlan driver, but only one of which validates things properly. Fix this. From Alvin Šipraga. 3) Missing of_node_put() in gianfar probing, from Sumera Priyadarsini. 4) Preserve device wanted feature bits across multiple netlink ethtool requests, from Maxim Mikityanskiy. 5) Fix rcu_sched stall in task and task_file bpf iterators, from Yonghong Song. 6) Avoid reset after device destroy in ena driver, from Shay Agroskin. 7) Missing memset() in netlink policy export reallocation path, from Johannes Berg. 8) Fix info leak in __smc_diag_dump(), from Peilin Ye. 9) Decapsulate ECN properly for ipv6 in ipv4 tunnels, from Mark Tomlinson. 10) Fix number of data stream negotiation in SCTP, from David Laight. 11) Fix double free in connection tracker action module, from Alaa Hleihel. 12) Don't allow empty NHA_GROUP attributes, from Nikolay Aleksandrov" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (46 commits) net: nexthop: don't allow empty NHA_GROUP bpf: Fix two typos in uapi/linux/bpf.h net: dsa: b53: check for timeout tipc: call rcu_read_lock() in tipc_aead_encrypt_done() net/sched: act_ct: Fix skb double-free in tcf_ct_handle_fragments() error flow net: sctp: Fix negotiation of the number of data streams. dt-bindings: net: renesas, ether: Improve schema validation gre6: Fix reception with IP6_TNL_F_RCV_DSCP_COPY hv_netvsc: Fix the queue_mapping in netvsc_vf_xmit() hv_netvsc: Remove "unlikely" from netvsc_select_queue bpf: selftests: global_funcs: Check err_str before strstr bpf: xdp: Fix XDP mode when no mode flags specified selftests/bpf: Remove test_align leftovers tools/resolve_btfids: Fix sections with wrong alignment net/smc: Prevent kernel-infoleak in __smc_diag_dump() sfc: fix build warnings on 32-bit net: phy: mscc: Fix a couple of spelling mistakes "spcified" -> "specified" libbpf: Fix map index used in error message net: gemini: Fix missing free_netdev() in error path of gemini_ethernet_port_probe() net: atlantic: Use readx_poll_timeout() for large timeout ...
| * | | | net: nexthop: don't allow empty NHA_GROUPNikolay Aleksandrov2020-08-221-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the nexthop code will use an empty NHA_GROUP attribute, but it requires at least 1 entry in order to function properly. Otherwise we end up derefencing null or random pointers all over the place due to not having any nh_grp_entry members allocated, nexthop code relies on having at least the first member present. Empty NHA_GROUP doesn't make any sense so just disallow it. Also add a WARN_ON for any future users of nexthop_create_group(). BUG: kernel NULL pointer dereference, address: 0000000000000080 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 0 PID: 558 Comm: ip Not tainted 5.9.0-rc1+ #93 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014 RIP: 0010:fib_check_nexthop+0x4a/0xaa Code: 0f 84 83 00 00 00 48 c7 02 80 03 f7 81 c3 40 80 fe fe 75 12 b8 ea ff ff ff 48 85 d2 74 6b 48 c7 02 40 03 f7 81 c3 48 8b 40 10 <48> 8b 80 80 00 00 00 eb 36 80 78 1a 00 74 12 b8 ea ff ff ff 48 85 RSP: 0018:ffff88807983ba00 EFLAGS: 00010213 RAX: 0000000000000000 RBX: ffff88807983bc00 RCX: 0000000000000000 RDX: ffff88807983bc00 RSI: 0000000000000000 RDI: ffff88807bdd0a80 RBP: ffff88807983baf8 R08: 0000000000000dc0 R09: 000000000000040a R10: 0000000000000000 R11: ffff88807bdd0ae8 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88807bea3100 R15: 0000000000000001 FS: 00007f10db393700(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000080 CR3: 000000007bd0f004 CR4: 00000000003706f0 Call Trace: fib_create_info+0x64d/0xaf7 fib_table_insert+0xf6/0x581 ? __vma_adjust+0x3b6/0x4d4 inet_rtm_newroute+0x56/0x70 rtnetlink_rcv_msg+0x1e3/0x20d ? rtnl_calcit.isra.0+0xb8/0xb8 netlink_rcv_skb+0x5b/0xac netlink_unicast+0xfa/0x17b netlink_sendmsg+0x334/0x353 sock_sendmsg_nosec+0xf/0x3f ____sys_sendmsg+0x1a0/0x1fc ? copy_msghdr_from_user+0x4c/0x61 ___sys_sendmsg+0x63/0x84 ? handle_mm_fault+0xa39/0x11b5 ? sockfd_lookup_light+0x72/0x9a __sys_sendmsg+0x50/0x6e do_syscall_64+0x54/0xbe entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f10dacc0bb7 Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb cd 66 0f 1f 44 00 00 8b 05 9a 4b 2b 00 85 c0 75 2e 48 63 ff 48 63 d2 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 b1 f2 2a 00 f7 d8 64 89 02 48 RSP: 002b:00007ffcbe628bf8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ffcbe628f80 RCX: 00007f10dacc0bb7 RDX: 0000000000000000 RSI: 00007ffcbe628c60 RDI: 0000000000000003 RBP: 000000005f41099c R08: 0000000000000001 R09: 0000000000000008 R10: 00000000000005e9 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffcbe628d70 R15: 0000563a86c6e440 Modules linked in: CR2: 0000000000000080 CC: David Ahern <dsahern@gmail.com> Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Reported-by: syzbot+a61aa19b0c14c8770bd9@syzkaller.appspotmail.com Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2020-08-2112-24/+78
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alexei Starovoitov says: ==================== pull-request: bpf 2020-08-21 The following pull-request contains BPF updates for your *net* tree. We've added 11 non-merge commits during the last 5 day(s) which contain a total of 12 files changed, 78 insertions(+), 24 deletions(-). The main changes are: 1) three fixes in BPF task iterator logic, from Yonghong. 2) fix for compressed dwarf sections in vmlinux, from Jiri. 3) fix xdp attach regression, from Andrii. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | * | | | bpf: Fix two typos in uapi/linux/bpf.hTobias Klauser2020-08-212-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also remove trailing whitespaces in bpf_skb_get_tunnel_key example code. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200821133642.18870-1-tklauser@distanz.ch
| | * | | | bpf: selftests: global_funcs: Check err_str before strstrYauheni Kaliuta2020-08-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The error path in libbpf.c:load_program() has calls to pr_warn() which ends up for global_funcs tests to test_global_funcs.c:libbpf_debug_print(). For the tests with no struct test_def::err_str initialized with a string, it causes call of strstr() with NULL as the second argument and it segfaults. Fix it by calling strstr() only for non-NULL err_str. Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200820115843.39454-1-yauheni.kaliuta@redhat.com
| | * | | | bpf: xdp: Fix XDP mode when no mode flags specifiedAndrii Nakryiko2020-08-201-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 7f0a838254bd ("bpf, xdp: Maintain info on attached XDP BPF programs in net_device") inadvertently changed which XDP mode is assumed when no mode flags are specified explicitly. Previously, driver mode was preferred, if driver supported it. If not, generic SKB mode was chosen. That commit changed default to SKB mode always. This patch fixes the issue and restores the original logic. Fixes: 7f0a838254bd ("bpf, xdp: Maintain info on attached XDP BPF programs in net_device") Reported-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/bpf/20200820052841.1559757-1-andriin@fb.com
| | * | | | selftests/bpf: Remove test_align leftoversVeronika Kabatova2020-08-202-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Calling generic selftests "make install" fails as rsync expects all files from TEST_GEN_PROGS to be present. The binary is not generated anymore (commit 3b09d27cc93d) so we can safely remove it from there and also from gitignore. Fixes: 3b09d27cc93d ("selftests/bpf: Move test_align under test_progs") Signed-off-by: Veronika Kabatova <vkabatov@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/20200819160710.1345956-1-vkabatov@redhat.com
| | * | | | tools/resolve_btfids: Fix sections with wrong alignmentJiri Olsa2020-08-201-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The data of compressed section should be aligned to 4 (for 32bit) or 8 (for 64 bit) bytes. The binutils ld sets sh_addralign to 1, which makes libelf fail with misaligned section error during the update as reported by Jesper: FAILED elf_update(WRITE): invalid section alignment While waiting for ld fix, we can fix compressed sections sh_addralign value manually. Adding warning in -vv mode when the fix is triggered: $ ./tools/bpf/resolve_btfids/resolve_btfids -vv vmlinux ... section(36) .comment, size 44, link 0, flags 30, type=1 section(37) .debug_aranges, size 45684, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 16, expected 8 section(38) .debug_info, size 129104957, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(39) .debug_abbrev, size 1152583, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(40) .debug_line, size 7374522, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(41) .debug_frame, size 702463, link 0, flags 800, type=1 section(42) .debug_str, size 1017571, link 0, flags 830, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(43) .debug_loc, size 3019453, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 1, expected 8 section(44) .debug_ranges, size 1744583, link 0, flags 800, type=1 - fixing wrong alignment sh_addralign 16, expected 8 section(45) .symtab, size 2955888, link 46, flags 0, type=2 section(46) .strtab, size 2613072, link 0, flags 0, type=3 ... update ok for vmlinux Another workaround is to disable compressed debug info data CONFIG_DEBUG_INFO_COMPRESSED kernel option. Fixes: fbbb68de80a4 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object") Reported-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Yonghong Song <yhs@fb.com> Cc: Mark Wielaard <mjw@redhat.com> Cc: Nick Clifton <nickc@redhat.com> Link: https://lore.kernel.org/bpf/20200819092342.259004-1-jolsa@kernel.org
| | * | | | libbpf: Fix map index used in error messageToke Høiland-Jørgensen2020-08-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The error message emitted by bpf_object__init_user_btf_maps() was using the wrong section ID. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200819110534.9058-1-toke@redhat.com
| | * | | | bpftool: Handle EAGAIN error code properly in pids collectionYonghong Song2020-08-181-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the error code is EAGAIN, the kernel signals the user space should retry the read() operation for bpf iterators. Let us do it. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200818222312.2181675-1-yhs@fb.com
| | * | | | bpf: Avoid visit same object multiple timesYonghong Song2020-08-181-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when traversing all tasks, the next tid is always increased by one. This may result in visiting the same task multiple times in a pid namespace. This patch fixed the issue by seting the next tid as pid_nr_ns(pid, ns) + 1, similar to funciton next_tgid(). Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Rik van Riel <riel@surriel.com> Link: https://lore.kernel.org/bpf/20200818222310.2181500-1-yhs@fb.com
| | * | | | bpf: Fix a rcu_sched stall issue with bpf task/task_file iteratorYonghong Song2020-08-181-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In our production system, we observed rcu stalls when 'bpftool prog` is running. rcu: INFO: rcu_sched self-detected stall on CPU rcu: \x097-....: (20999 ticks this GP) idle=302/1/0x4000000000000000 softirq=1508852/1508852 fqs=4913 \x09(t=21031 jiffies g=2534773 q=179750) NMI backtrace for cpu 7 CPU: 7 PID: 184195 Comm: bpftool Kdump: loaded Tainted: G W 5.8.0-00004-g68bfc7f8c1b4 #6 Hardware name: Quanta Twin Lakes MP/Twin Lakes Passive MP, BIOS F09_3A17 05/03/2019 Call Trace: <IRQ> dump_stack+0x57/0x70 nmi_cpu_backtrace.cold+0x14/0x53 ? lapic_can_unplug_cpu.cold+0x39/0x39 nmi_trigger_cpumask_backtrace+0xb7/0xc7 rcu_dump_cpu_stacks+0xa2/0xd0 rcu_sched_clock_irq.cold+0x1ff/0x3d9 ? tick_nohz_handler+0x100/0x100 update_process_times+0x5b/0x90 tick_sched_timer+0x5e/0xf0 __hrtimer_run_queues+0x12a/0x2a0 hrtimer_interrupt+0x10e/0x280 __sysvec_apic_timer_interrupt+0x51/0xe0 asm_call_on_stack+0xf/0x20 </IRQ> sysvec_apic_timer_interrupt+0x6f/0x80 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:task_file_seq_get_next+0x71/0x220 Code: 00 00 8b 53 1c 49 8b 7d 00 89 d6 48 8b 47 20 44 8b 18 41 39 d3 76 75 48 8b 4f 20 8b 01 39 d0 76 61 41 89 d1 49 39 c1 48 19 c0 <48> 8b 49 08 21 d0 48 8d 04 c1 4c 8b 08 4d 85 c9 74 46 49 8b 41 38 RSP: 0018:ffffc90006223e10 EFLAGS: 00000297 RAX: ffffffffffffffff RBX: ffff888f0d172388 RCX: ffff888c8c07c1c0 RDX: 00000000000f017b RSI: 00000000000f017b RDI: ffff888c254702c0 RBP: ffffc90006223e68 R08: ffff888be2a1c140 R09: 00000000000f017b R10: 0000000000000002 R11: 0000000000100000 R12: ffff888f23c24118 R13: ffffc90006223e60 R14: ffffffff828509a0 R15: 00000000ffffffff task_file_seq_next+0x52/0xa0 bpf_seq_read+0xb9/0x320 vfs_read+0x9d/0x180 ksys_read+0x5f/0xe0 do_syscall_64+0x38/0x60 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f8815f4f76e Code: c0 e9 f6 fe ff ff 55 48 8d 3d 76 70 0a 00 48 89 e5 e8 36 06 02 00 66 0f 1f 44 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 52 c3 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 RSP: 002b:00007fff8f9df578 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000000000170b9c0 RCX: 00007f8815f4f76e RDX: 0000000000001000 RSI: 00007fff8f9df5b0 RDI: 0000000000000007 RBP: 00007fff8f9e05f0 R08: 0000000000000049 R09: 0000000000000010 R10: 00007f881601fa40 R11: 0000000000000246 R12: 00007fff8f9e05a8 R13: 00007fff8f9e05a8 R14: 0000000001917f90 R15: 000000000000e22e Note that `bpftool prog` actually calls a task_file bpf iterator program to establish an association between prog/map/link/btf anon files and processes. In the case where the above rcu stall occured, we had a process having 1587 tasks and each task having roughly 81305 files. This implied 129 million bpf prog invocations. Unfortunwtely none of these files are prog/map/link/btf files so bpf iterator/prog needs to traverse all these files and not able to return to user space since there are no seq_file buffer overflow. This patch fixed the issue in bpf_seq_read() to limit the number of visited objects. If the maximum number of visited objects is reached, no more objects will be visited in the current syscall. If there is nothing written in the seq_file buffer, -EAGAIN will return to the user so user can try again. The maximum number of visited objects is set at 1 million. In our Intel Xeon D-2191 2.3GHZ 18-core server, bpf_seq_read() visiting 1 million files takes around 0.18 seconds. We did not use cond_resched() since for some iterators, e.g., netlink iterator, where rcu read_lock critical section spans between consecutive seq_ops->next(), which makes impossible to do cond_resched() in the key while loop of function bpf_seq_read(). Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/bpf/20200818222309.2181348-1-yhs@fb.com
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-18 23:30:14 +0000