/* * Ptrace test for TAR, PPR, DSCR registers * * Copyright (C) 2015 Anshuman Khandual, IBM Corporation. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include "ptrace.h" #include "ptrace-tar.h" /* Tracer and Tracee Shared Data */ int shm_id; int *cptr; int *pptr; void tar(void) { unsigned long reg[3]; int ret; cptr = (int *)shmat(shm_id, NULL, 0); printf("%-30s TAR: %u PPR: %lx DSCR: %u\n", user_write, TAR_1, PPR_1, DSCR_1); mtspr(SPRN_TAR, TAR_1); mtspr(SPRN_PPR, PPR_1); mtspr(SPRN_DSCR, DSCR_1); cptr[2] = 1; /* Wait on parent */ while (!cptr[0]) asm volatile("" : : : "memory"); reg[0] = mfspr(SPRN_TAR); reg[1] = mfspr(SPRN_PPR); reg[2] = mfspr(SPRN_DSCR); printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n", user_read, reg[0], reg[1], reg[2]); /* Unblock the parent now */ cptr[1] = 1; shmdt((int *)cptr); ret = validate_tar_registers(reg, TAR_2, PPR_2, DSCR_2); if (ret) exit(1); exit(0); } int trace_tar(pid_t child) { unsigned long reg[3]; FAIL_IF(start_trace(child)); FAIL_IF(show_tar_registers(child, reg)); printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n", ptrace_read_running, reg[0], reg[1], reg[2]); FAIL_IF(validate_tar_registers(reg, TAR_1, PPR_1, DSCR_1)); FAIL_IF(stop_trace(child)); return TEST_PASS; } int trace_tar_write(pid_t child) { FAIL_IF(start_trace(child)); FAIL_IF(write_tar_registers(child, TAR_2, PPR_2, DSCR_2)); printf("%-30s TAR: %u PPR: %lx DSCR: %u\n", ptrace_write_running, TAR_2, PPR_2, DSCR_2); FAIL_IF(stop_trace(child)); return TEST_PASS; } int ptrace_tar(void) { pid_t pid; int ret, status; shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT); pid = fork(); if (pid < 0) { perror("fork() failed"); return TEST_FAIL; } if (pid == 0) tar(); if (pid) { pptr = (int *)shmat(shm_id, NULL, 0); pptr[0] = 0; pptr[1] = 0; while (!pptr[2]) asm volatile("" : : : "memory"); ret = trace_tar(pid); if (ret) return ret; ret = trace_tar_write(pid); if (ret) return ret; /* Unblock the child now */ pptr[0] = 1; /* Wait on child */ while (!pptr[1]) asm volatile("" : : : "memory"); shmdt((int *)pptr); ret = wait(&status); shmctl(shm_id, IPC_RMID, NULL); if (ret != pid) { printf("Child's exit status not captured\n"); return TEST_PASS; } return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL : TEST_PASS; } return TEST_PASS; } int main(int argc, char *argv[]) { return test_harness(ptrace_tar, "ptrace_tar"); } t/commit/?id=d7df2443cd5f67fc6ee7c05a88e4996e8177f91b'>root/sound/pci/ymfpci/ymfpci.c
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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2017-02-03 17:10:28 +1100
committerMichael Ellerman <mpe@ellerman.id.au>2017-02-08 23:36:29 +1100
commitd7df2443cd5f67fc6ee7c05a88e4996e8177f91b (patch)
tree098a7c0ca4fceb8a65cb1f693c9d71990388933d /sound/pci/ymfpci/ymfpci.c
parenta0615a16f7d0ceb5804d295203c302d496d8ee91 (diff)
powerpc/mm: Fix spurrious segfaults on radix with autonuma
When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'sound/pci/ymfpci/ymfpci.c')