/****************************************************************************** * * Module Name: getopt * *****************************************************************************/ /* * Copyright (C) 2000 - 2016, Intel Corp. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer, * without modification. * 2. Redistributions in binary form must reproduce at minimum a disclaimer * substantially similar to the "NO WARRANTY" disclaimer below * ("Disclaimer") and any redistribution must be conditioned upon * including a substantially similar Disclaimer requirement for further * binary redistribution. * 3. Neither the names of the above-listed copyright holders nor the names * of any contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * NO WARRANTY * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGES. */ /* * ACPICA getopt() implementation * * Option strings: * "f" - Option has no arguments * "f:" - Option requires an argument * "f+" - Option has an optional argument * "f^" - Option has optional single-char sub-options * "f|" - Option has required single-char sub-options */ #include #include "accommon.h" #include "acapps.h" #define ACPI_OPTION_ERROR(msg, badchar) \ if (acpi_gbl_opterr) {fprintf (stderr, "%s%c\n", msg, badchar);} int acpi_gbl_opterr = 1; int acpi_gbl_optind = 1; int acpi_gbl_sub_opt_char = 0; char *acpi_gbl_optarg; static int current_char_ptr = 1; /******************************************************************************* * * FUNCTION: acpi_getopt_argument * * PARAMETERS: argc, argv - from main * * RETURN: 0 if an argument was found, -1 otherwise. Sets acpi_gbl_Optarg * to point to the next argument. * * DESCRIPTION: Get the next argument. Used to obtain arguments for the * two-character options after the original call to acpi_getopt. * Note: Either the argument starts at the next character after * the option, or it is pointed to by the next argv entry. * (After call to acpi_getopt, we need to backup to the previous * argv entry). * ******************************************************************************/ int acpi_getopt_argument(int argc, char **argv) { acpi_gbl_optind--; current_char_ptr++; if (argv[acpi_gbl_optind][(int)(current_char_ptr + 1)] != '\0') { acpi_gbl_optarg = &argv[acpi_gbl_optind++][(int)(current_char_ptr + 1)]; } else if (++acpi_gbl_optind >= argc) { ACPI_OPTION_ERROR("\nOption requires an argument", 0); current_char_ptr = 1; return (-1); } else { acpi_gbl_optarg = argv[acpi_gbl_optind++]; } current_char_ptr = 1; return (0); } /******************************************************************************* * * FUNCTION: acpi_getopt * * PARAMETERS: argc, argv - from main * opts - options info list * * RETURN: Option character or ACPI_OPT_END * * DESCRIPTION: Get the next option * ******************************************************************************/ int acpi_getopt(int argc, char **argv, char *opts) { int current_char; char *opts_ptr; if (current_char_ptr == 1) { if (acpi_gbl_optind >= argc || argv[acpi_gbl_optind][0] != '-' || argv[acpi_gbl_optind][1] == '\0') { return (ACPI_OPT_END); } else if (strcmp(argv[acpi_gbl_optind], "--") == 0) { acpi_gbl_optind++; return (ACPI_OPT_END); } } /* Get the option */ current_char = argv[acpi_gbl_optind][current_char_ptr]; /* Make sure that the option is legal */ if (current_char == ':' || (opts_ptr = strchr(opts, current_char)) == NULL) { ACPI_OPTION_ERROR("Illegal option: -", current_char); if (argv[acpi_gbl_optind][++current_char_ptr] == '\0') { acpi_gbl_optind++; current_char_ptr = 1; } return ('?'); } /* Option requires an argument? */ if (*++opts_ptr == ':') { if (argv[acpi_gbl_optind][(int)(current_char_ptr + 1)] != '\0') { acpi_gbl_optarg = &argv[acpi_gbl_optind++][(int) (current_char_ptr + 1)]; } else if (++acpi_gbl_optind >= argc) { ACPI_OPTION_ERROR("Option requires an argument: -", current_char); current_char_ptr = 1; return ('?'); } else { acpi_gbl_optarg = argv[acpi_gbl_optind++]; } current_char_ptr = 1; } /* Option has an optional argument? */ else if (*opts_ptr == '+') { if (argv[acpi_gbl_optind][(int)(current_char_ptr + 1)] != '\0') { acpi_gbl_optarg = &argv[acpi_gbl_optind++][(int) (current_char_ptr + 1)]; } else if (++acpi_gbl_optind >= argc) { acpi_gbl_optarg = NULL; } else { acpi_gbl_optarg = argv[acpi_gbl_optind++]; } current_char_ptr = 1; } /* Option has optional single-char arguments? */ else if (*opts_ptr == '^') { if (argv[acpi_gbl_optind][(int)(current_char_ptr + 1)] != '\0') { acpi_gbl_optarg = &argv[acpi_gbl_optind][(int)(current_char_ptr + 1)]; } else { acpi_gbl_optarg = "^"; } acpi_gbl_sub_opt_char = acpi_gbl_optarg[0]; acpi_gbl_optind++; current_char_ptr = 1; } /* Option has a required single-char argument? */ else if (*opts_ptr == '|') { if (argv[acpi_gbl_optind][(int)(current_char_ptr + 1)] != '\0') { acpi_gbl_optarg = &argv[acpi_gbl_optind][(int)(current_char_ptr + 1)]; } else { ACPI_OPTION_ERROR ("Option requires a single-character suboption: -", current_char); current_char_ptr = 1; return ('?'); } acpi_gbl_sub_opt_char = acpi_gbl_optarg[0]; acpi_gbl_optind++; current_char_ptr = 1; } /* Option with no arguments */ else { if (argv[acpi_gbl_optind][++current_char_ptr] == '\0') { current_char_ptr = 1; acpi_gbl_optind++; } acpi_gbl_optarg = NULL; } return (current_char); } n "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'tools/testing/selftests/powerpc/signal/Makefile')