Suzuki K Poulose 3ff44563db coresight: tmc-etr: Do not call smp_processor_id() from preemptible ... During a perf session we try to allocate buffers on the "node" associated with the CPU the event is bound to. If it's not bound to a CPU, we use the current CPU node, using smp_processor_id(). However this is unsafe in a pre-emptible context and could generate the splats as below : BUG: using smp_processor_id() in preemptible [00000000] code: perf/1743 caller is alloc_etr_buf.isra.6+0x80/0xa0 CPU: 1 PID: 1743 Comm: perf Not tainted 5.1.0-rc6-147786-g116841e #344 Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Feb 1 2019 Call trace: dump_backtrace+0x0/0x150 show_stack+0x14/0x20 dump_stack+0x9c/0xc4 debug_smp_processor_id+0x10c/0x110 alloc_etr_buf.isra.6+0x80/0xa0 tmc_alloc_etr_buffer+0x12c/0x1f0 etm_setup_aux+0x1c4/0x230 rb_alloc_aux+0x1b8/0x2b8 perf_mmap+0x35c/0x478 mmap_region+0x34c/0x4f0 do_mmap+0x2d8/0x418 vm_mmap_pgoff+0xd0/0xf8 ksys_mmap_pgoff+0x88/0xf8 __arm64_sys_mmap+0x28/0x38 el0_svc_handler+0xd8/0x138 el0_svc+0x8/0xc Use NUMA_NO_NODE hint instead of using the current node for events not bound to CPUs. Fixes: 855ab61c16 ("coresight: tmc-etr: Refactor function tmc_etr_setup_perf_buf()") Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20190620221237.3536-2-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2019-07-03 21:15:33 +02:00
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coresight	coresight: tmc-etr: Do not call smp_processor_id() from preemptible	2019-07-03 21:15:33 +02:00
intel_th	intel_th: msu: Start read iterator from a non-empty window	2019-07-03 17:45:57 +02:00
stm	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00