Revision 809b1e4945774c9ec5619a8f4e2189b7b3833c0c authored by Hannes Reinecke on 21 January 2021, 17:50:56 UTC, committed by Mike Snitzer on 21 January 2021, 20:06:45 UTC
This reverts commit 644bda6f3460 ("dm table: fall back to getting device using name_to_dev_t()") dm_get_dev_t() is just used to convert an arbitrary 'path' string into a dev_t. It doesn't presume that the device is present; that check will be done later, as the only caller is dm_get_device(), which does a dm_get_table_device() later on, which will properly open the device. So if the path string already _is_ in major:minor representation we can convert it directly, avoiding a recursion into the filesystem to lookup the block device. This avoids a hang in multipath_message() when the filesystem is inaccessible. Fixes: 644bda6f3460 ("dm table: fall back to getting device using name_to_dev_t()") Cc: stable@vger.kernel.org Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Martin Wilck <mwilck@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
1 parent 004b8ae
backtracetest.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Simple stack backtrace regression test module
*
* (C) Copyright 2008 Intel Corporation
* Author: Arjan van de Ven <arjan@linux.intel.com>
*/
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/stacktrace.h>
static void backtrace_test_normal(void)
{
pr_info("Testing a backtrace from process context.\n");
pr_info("The following trace is a kernel self test and not a bug!\n");
dump_stack();
}
static DECLARE_COMPLETION(backtrace_work);
static void backtrace_test_irq_callback(unsigned long data)
{
dump_stack();
complete(&backtrace_work);
}
static DECLARE_TASKLET_OLD(backtrace_tasklet, &backtrace_test_irq_callback);
static void backtrace_test_irq(void)
{
pr_info("Testing a backtrace from irq context.\n");
pr_info("The following trace is a kernel self test and not a bug!\n");
init_completion(&backtrace_work);
tasklet_schedule(&backtrace_tasklet);
wait_for_completion(&backtrace_work);
}
#ifdef CONFIG_STACKTRACE
static void backtrace_test_saved(void)
{
unsigned long entries[8];
unsigned int nr_entries;
pr_info("Testing a saved backtrace.\n");
pr_info("The following trace is a kernel self test and not a bug!\n");
nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0);
stack_trace_print(entries, nr_entries, 0);
}
#else
static void backtrace_test_saved(void)
{
pr_info("Saved backtrace test skipped.\n");
}
#endif
static int backtrace_regression_test(void)
{
pr_info("====[ backtrace testing ]===========\n");
backtrace_test_normal();
backtrace_test_irq();
backtrace_test_saved();
pr_info("====[ end of backtrace testing ]====\n");
return 0;
}
static void exitf(void)
{
}
module_init(backtrace_regression_test);
module_exit(exitf);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...