2010-12-28 15:25:21 -07:00
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|
|
/*
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* Persistent Storage - platform driver interface parts.
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*
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2012-05-26 07:20:19 -06:00
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* Copyright (C) 2007-2008 Google, Inc.
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2010-12-28 15:25:21 -07:00
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* Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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2014-06-06 15:37:31 -06:00
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#define pr_fmt(fmt) "pstore: " fmt
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2010-12-28 15:25:21 -07:00
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#include <linux/atomic.h>
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#include <linux/types.h>
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/kmsg_dump.h>
|
2012-05-26 07:20:19 -06:00
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#include <linux/console.h>
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2010-12-28 15:25:21 -07:00
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#include <linux/module.h>
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|
|
#include <linux/pstore.h>
|
2016-02-18 07:04:22 -07:00
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|
|
#ifdef CONFIG_PSTORE_ZLIB_COMPRESS
|
2013-08-16 14:53:10 -06:00
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|
#include <linux/zlib.h>
|
2016-02-18 07:04:22 -07:00
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|
#endif
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|
|
#ifdef CONFIG_PSTORE_LZO_COMPRESS
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#include <linux/lzo.h>
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#endif
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#ifdef CONFIG_PSTORE_LZ4_COMPRESS
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#include <linux/lz4.h>
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|
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#endif
|
2010-12-28 15:25:21 -07:00
|
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|
#include <linux/string.h>
|
2011-08-11 16:14:39 -06:00
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|
#include <linux/timer.h>
|
2010-12-28 15:25:21 -07:00
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#include <linux/slab.h>
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|
|
#include <linux/uaccess.h>
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2011-08-12 11:54:51 -06:00
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#include <linux/hardirq.h>
|
2012-05-26 07:20:28 -06:00
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#include <linux/jiffies.h>
|
2011-08-11 16:14:39 -06:00
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#include <linux/workqueue.h>
|
2010-12-28 15:25:21 -07:00
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#include "internal.h"
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2011-08-11 16:14:39 -06:00
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/*
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* We defer making "oops" entries appear in pstore - see
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* whether the system is actually still running well enough
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* to let someone see the entry
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*/
|
pstore/platform: Disable automatic updates by default
Having automatic updates seems pointless for production system, and
even dangerous and thus counter-productive:
1. If we can mount pstore, or read files, we can as well read
/proc/kmsg. So, there's little point in duplicating the
functionality and present the same information but via another
userland ABI;
2. Expecting the kernel to behave sanely after oops/panic is naive.
It might work, but you'd rather not try it. Screwed up kernel
can do rather bad things, like recursive faults[1]; and pstore
rather provoking bad things to happen. It uses:
1. Timers (assumes sane interrupts state);
2. Workqueues and mutexes (assumes scheduler in a sane state);
3. kzalloc (a working slab allocator);
That's too much for a dead kernel, so the debugging facility
itself might just make debugging harder, which is not what
we want.
Maybe for non-oops message types it would make sense to re-enable
automatic updates, but so far I don't see any use case for this.
Even for tracing, it has its own run-time/normal ABI, so we're
only interested in pstore upon next boot, to retrieve what has
gone wrong with HW or SW.
So, let's disable the updates by default.
[1]
BUG: unable to handle kernel paging request at fffffffffffffff8
IP: [<ffffffff8104801b>] kthread_data+0xb/0x20
[...]
Process kworker/0:1 (pid: 14, threadinfo ffff8800072c0000, task ffff88000725b100)
[...
Call Trace:
[<ffffffff81043710>] wq_worker_sleeping+0x10/0xa0
[<ffffffff813687a8>] __schedule+0x568/0x7d0
[<ffffffff8106c24d>] ? trace_hardirqs_on+0xd/0x10
[<ffffffff81087e22>] ? call_rcu_sched+0x12/0x20
[<ffffffff8102b596>] ? release_task+0x156/0x2d0
[<ffffffff8102b45e>] ? release_task+0x1e/0x2d0
[<ffffffff8106c24d>] ? trace_hardirqs_on+0xd/0x10
[<ffffffff81368ac4>] schedule+0x24/0x70
[<ffffffff8102cba8>] do_exit+0x1f8/0x370
[<ffffffff810051e7>] oops_end+0x77/0xb0
[<ffffffff8135c301>] no_context+0x1a6/0x1b5
[<ffffffff8135c4de>] __bad_area_nosemaphore+0x1ce/0x1ed
[<ffffffff81053156>] ? ttwu_queue+0xc6/0xe0
[<ffffffff8135c50b>] bad_area_nosemaphore+0xe/0x10
[<ffffffff8101fa47>] do_page_fault+0x2c7/0x450
[<ffffffff8106e34b>] ? __lock_release+0x6b/0xe0
[<ffffffff8106bf21>] ? mark_held_locks+0x61/0x140
[<ffffffff810502fe>] ? __wake_up+0x4e/0x70
[<ffffffff81185f7d>] ? trace_hardirqs_off_thunk+0x3a/0x3c
[<ffffffff81158970>] ? pstore_register+0x120/0x120
[<ffffffff8136a37f>] page_fault+0x1f/0x30
[<ffffffff81158970>] ? pstore_register+0x120/0x120
[<ffffffff81185ab8>] ? memcpy+0x68/0x110
[<ffffffff8115875a>] ? pstore_get_records+0x3a/0x130
[<ffffffff811590f4>] ? persistent_ram_copy_old+0x64/0x90
[<ffffffff81158bf4>] ramoops_pstore_read+0x84/0x130
[<ffffffff81158799>] pstore_get_records+0x79/0x130
[<ffffffff81042536>] ? process_one_work+0x116/0x450
[<ffffffff81158970>] ? pstore_register+0x120/0x120
[<ffffffff8115897e>] pstore_dowork+0xe/0x10
[<ffffffff81042594>] process_one_work+0x174/0x450
[<ffffffff81042536>] ? process_one_work+0x116/0x450
[<ffffffff81042e13>] worker_thread+0x123/0x2d0
[<ffffffff81042cf0>] ? manage_workers.isra.28+0x120/0x120
[<ffffffff81047d8e>] kthread+0x8e/0xa0
[<ffffffff8136ba74>] kernel_thread_helper+0x4/0x10
[<ffffffff8136a199>] ? retint_restore_args+0xe/0xe
[<ffffffff81047d00>] ? __init_kthread_worker+0x70/0x70
[<ffffffff8136ba70>] ? gs_change+0xb/0xb
Code: be e2 00 00 00 48 c7 c7 d1 2a 4e 81 e8 bf fb fd ff 48 8b 5d f0 4c 8b 65 f8 c9 c3 0f 1f 44 00 00 48 8b 87 08 02 00 00 55 48 89 e5 <48> 8b 40 f8 5d c3 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00
RIP [<ffffffff8104801b>] kthread_data+0xb/0x20
RSP <ffff8800072c1888>
CR2: fffffffffffffff8
---[ end trace 996a332dc399111d ]---
Fixing recursive fault but reboot is needed!
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-26 07:20:29 -06:00
|
|
|
static int pstore_update_ms = -1;
|
2012-05-26 07:20:28 -06:00
|
|
|
module_param_named(update_ms, pstore_update_ms, int, 0600);
|
|
|
|
MODULE_PARM_DESC(update_ms, "milliseconds before pstore updates its content "
|
pstore/platform: Disable automatic updates by default
Having automatic updates seems pointless for production system, and
even dangerous and thus counter-productive:
1. If we can mount pstore, or read files, we can as well read
/proc/kmsg. So, there's little point in duplicating the
functionality and present the same information but via another
userland ABI;
2. Expecting the kernel to behave sanely after oops/panic is naive.
It might work, but you'd rather not try it. Screwed up kernel
can do rather bad things, like recursive faults[1]; and pstore
rather provoking bad things to happen. It uses:
1. Timers (assumes sane interrupts state);
2. Workqueues and mutexes (assumes scheduler in a sane state);
3. kzalloc (a working slab allocator);
That's too much for a dead kernel, so the debugging facility
itself might just make debugging harder, which is not what
we want.
Maybe for non-oops message types it would make sense to re-enable
automatic updates, but so far I don't see any use case for this.
Even for tracing, it has its own run-time/normal ABI, so we're
only interested in pstore upon next boot, to retrieve what has
gone wrong with HW or SW.
So, let's disable the updates by default.
[1]
BUG: unable to handle kernel paging request at fffffffffffffff8
IP: [<ffffffff8104801b>] kthread_data+0xb/0x20
[...]
Process kworker/0:1 (pid: 14, threadinfo ffff8800072c0000, task ffff88000725b100)
[...
Call Trace:
[<ffffffff81043710>] wq_worker_sleeping+0x10/0xa0
[<ffffffff813687a8>] __schedule+0x568/0x7d0
[<ffffffff8106c24d>] ? trace_hardirqs_on+0xd/0x10
[<ffffffff81087e22>] ? call_rcu_sched+0x12/0x20
[<ffffffff8102b596>] ? release_task+0x156/0x2d0
[<ffffffff8102b45e>] ? release_task+0x1e/0x2d0
[<ffffffff8106c24d>] ? trace_hardirqs_on+0xd/0x10
[<ffffffff81368ac4>] schedule+0x24/0x70
[<ffffffff8102cba8>] do_exit+0x1f8/0x370
[<ffffffff810051e7>] oops_end+0x77/0xb0
[<ffffffff8135c301>] no_context+0x1a6/0x1b5
[<ffffffff8135c4de>] __bad_area_nosemaphore+0x1ce/0x1ed
[<ffffffff81053156>] ? ttwu_queue+0xc6/0xe0
[<ffffffff8135c50b>] bad_area_nosemaphore+0xe/0x10
[<ffffffff8101fa47>] do_page_fault+0x2c7/0x450
[<ffffffff8106e34b>] ? __lock_release+0x6b/0xe0
[<ffffffff8106bf21>] ? mark_held_locks+0x61/0x140
[<ffffffff810502fe>] ? __wake_up+0x4e/0x70
[<ffffffff81185f7d>] ? trace_hardirqs_off_thunk+0x3a/0x3c
[<ffffffff81158970>] ? pstore_register+0x120/0x120
[<ffffffff8136a37f>] page_fault+0x1f/0x30
[<ffffffff81158970>] ? pstore_register+0x120/0x120
[<ffffffff81185ab8>] ? memcpy+0x68/0x110
[<ffffffff8115875a>] ? pstore_get_records+0x3a/0x130
[<ffffffff811590f4>] ? persistent_ram_copy_old+0x64/0x90
[<ffffffff81158bf4>] ramoops_pstore_read+0x84/0x130
[<ffffffff81158799>] pstore_get_records+0x79/0x130
[<ffffffff81042536>] ? process_one_work+0x116/0x450
[<ffffffff81158970>] ? pstore_register+0x120/0x120
[<ffffffff8115897e>] pstore_dowork+0xe/0x10
[<ffffffff81042594>] process_one_work+0x174/0x450
[<ffffffff81042536>] ? process_one_work+0x116/0x450
[<ffffffff81042e13>] worker_thread+0x123/0x2d0
[<ffffffff81042cf0>] ? manage_workers.isra.28+0x120/0x120
[<ffffffff81047d8e>] kthread+0x8e/0xa0
[<ffffffff8136ba74>] kernel_thread_helper+0x4/0x10
[<ffffffff8136a199>] ? retint_restore_args+0xe/0xe
[<ffffffff81047d00>] ? __init_kthread_worker+0x70/0x70
[<ffffffff8136ba70>] ? gs_change+0xb/0xb
Code: be e2 00 00 00 48 c7 c7 d1 2a 4e 81 e8 bf fb fd ff 48 8b 5d f0 4c 8b 65 f8 c9 c3 0f 1f 44 00 00 48 8b 87 08 02 00 00 55 48 89 e5 <48> 8b 40 f8 5d c3 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00
RIP [<ffffffff8104801b>] kthread_data+0xb/0x20
RSP <ffff8800072c1888>
CR2: fffffffffffffff8
---[ end trace 996a332dc399111d ]---
Fixing recursive fault but reboot is needed!
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-26 07:20:29 -06:00
|
|
|
"(default is -1, which means runtime updates are disabled; "
|
|
|
|
"enabling this option is not safe, it may lead to further "
|
|
|
|
"corruption on Oopses)");
|
2011-08-11 16:14:39 -06:00
|
|
|
|
|
|
|
static int pstore_new_entry;
|
|
|
|
|
|
|
|
static void pstore_timefunc(unsigned long);
|
|
|
|
static DEFINE_TIMER(pstore_timer, pstore_timefunc, 0, 0);
|
|
|
|
|
|
|
|
static void pstore_dowork(struct work_struct *);
|
|
|
|
static DECLARE_WORK(pstore_work, pstore_dowork);
|
|
|
|
|
2010-12-28 15:25:21 -07:00
|
|
|
/*
|
|
|
|
* pstore_lock just protects "psinfo" during
|
|
|
|
* calls to pstore_register()
|
|
|
|
*/
|
|
|
|
static DEFINE_SPINLOCK(pstore_lock);
|
2012-07-09 18:10:41 -06:00
|
|
|
struct pstore_info *psinfo;
|
2010-12-28 15:25:21 -07:00
|
|
|
|
2011-07-21 14:57:55 -06:00
|
|
|
static char *backend;
|
|
|
|
|
2013-08-16 14:53:10 -06:00
|
|
|
/* Compression parameters */
|
2016-02-18 07:04:22 -07:00
|
|
|
#ifdef CONFIG_PSTORE_ZLIB_COMPRESS
|
2013-08-16 14:53:10 -06:00
|
|
|
#define COMPR_LEVEL 6
|
|
|
|
#define WINDOW_BITS 12
|
|
|
|
#define MEM_LEVEL 4
|
|
|
|
static struct z_stream_s stream;
|
2016-02-18 07:04:22 -07:00
|
|
|
#else
|
|
|
|
static unsigned char *workspace;
|
|
|
|
#endif
|
|
|
|
|
|
|
|
struct pstore_zbackend {
|
|
|
|
int (*compress)(const void *in, void *out, size_t inlen, size_t outlen);
|
|
|
|
int (*decompress)(void *in, void *out, size_t inlen, size_t outlen);
|
|
|
|
void (*allocate)(void);
|
|
|
|
void (*free)(void);
|
|
|
|
|
|
|
|
const char *name;
|
|
|
|
};
|
2013-08-16 14:53:10 -06:00
|
|
|
|
|
|
|
static char *big_oops_buf;
|
|
|
|
static size_t big_oops_buf_sz;
|
|
|
|
|
2011-03-18 16:33:43 -06:00
|
|
|
/* How much of the console log to snapshot */
|
2010-12-28 15:25:21 -07:00
|
|
|
static unsigned long kmsg_bytes = 10240;
|
|
|
|
|
2011-03-18 16:33:43 -06:00
|
|
|
void pstore_set_kmsg_bytes(int bytes)
|
2010-12-28 15:25:21 -07:00
|
|
|
{
|
2011-03-18 16:33:43 -06:00
|
|
|
kmsg_bytes = bytes;
|
2010-12-28 15:25:21 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Tag each group of saved records with a sequence number */
|
|
|
|
static int oopscount;
|
|
|
|
|
2012-03-16 16:36:59 -06:00
|
|
|
static const char *get_reason_str(enum kmsg_dump_reason reason)
|
|
|
|
{
|
|
|
|
switch (reason) {
|
|
|
|
case KMSG_DUMP_PANIC:
|
|
|
|
return "Panic";
|
|
|
|
case KMSG_DUMP_OOPS:
|
|
|
|
return "Oops";
|
|
|
|
case KMSG_DUMP_EMERG:
|
|
|
|
return "Emergency";
|
|
|
|
case KMSG_DUMP_RESTART:
|
|
|
|
return "Restart";
|
|
|
|
case KMSG_DUMP_HALT:
|
|
|
|
return "Halt";
|
|
|
|
case KMSG_DUMP_POWEROFF:
|
|
|
|
return "Poweroff";
|
|
|
|
default:
|
|
|
|
return "Unknown";
|
|
|
|
}
|
|
|
|
}
|
2011-03-22 17:01:49 -06:00
|
|
|
|
pstore: Avoid deadlock in panic and emergency-restart path
[Issue]
When pstore is in panic and emergency-restart paths, it may be blocked
in those paths because it simply takes spin_lock.
This is an example scenario which pstore may hang up in a panic path:
- cpuA grabs psinfo->buf_lock
- cpuB panics and calls smp_send_stop
- smp_send_stop sends IRQ to cpuA
- after 1 second, cpuB gives up on cpuA and sends an NMI instead
- cpuA is now in an NMI handler while still holding buf_lock
- cpuB is deadlocked
This case may happen if a firmware has a bug and
cpuA is stuck talking with it more than one second.
Also, this is a similar scenario in an emergency-restart path:
- cpuA grabs psinfo->buf_lock and stucks in a firmware
- cpuB kicks emergency-restart via either sysrq-b or hangcheck timer.
And then, cpuB is deadlocked by taking psinfo->buf_lock again.
[Solution]
This patch avoids the deadlocking issues in both panic and emergency_restart
paths by introducing a function, is_non_blocking_path(), to check if a cpu
can be blocked in current path.
With this patch, pstore is not blocked even if another cpu has
taken a spin_lock, in those paths by changing from spin_lock_irqsave
to spin_trylock_irqsave.
In addition, according to a comment of emergency_restart() in kernel/sys.c,
spin_lock shouldn't be taken in an emergency_restart path to avoid
deadlock. This patch fits the comment below.
<snip>
/**
* emergency_restart - reboot the system
*
* Without shutting down any hardware or taking any locks
* reboot the system. This is called when we know we are in
* trouble so this is our best effort to reboot. This is
* safe to call in interrupt context.
*/
void emergency_restart(void)
<snip>
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-01-11 11:09:41 -07:00
|
|
|
bool pstore_cannot_block_path(enum kmsg_dump_reason reason)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* In case of NMI path, pstore shouldn't be blocked
|
|
|
|
* regardless of reason.
|
|
|
|
*/
|
|
|
|
if (in_nmi())
|
|
|
|
return true;
|
|
|
|
|
|
|
|
switch (reason) {
|
|
|
|
/* In panic case, other cpus are stopped by smp_send_stop(). */
|
|
|
|
case KMSG_DUMP_PANIC:
|
|
|
|
/* Emergency restart shouldn't be blocked by spin lock. */
|
|
|
|
case KMSG_DUMP_EMERG:
|
|
|
|
return true;
|
|
|
|
default:
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(pstore_cannot_block_path);
|
|
|
|
|
2016-02-18 07:04:22 -07:00
|
|
|
#ifdef CONFIG_PSTORE_ZLIB_COMPRESS
|
2013-08-16 14:53:10 -06:00
|
|
|
/* Derived from logfs_compress() */
|
2016-02-18 07:04:22 -07:00
|
|
|
static int compress_zlib(const void *in, void *out, size_t inlen, size_t outlen)
|
2013-08-16 14:53:10 -06:00
|
|
|
{
|
|
|
|
int err, ret;
|
|
|
|
|
|
|
|
ret = -EIO;
|
|
|
|
err = zlib_deflateInit2(&stream, COMPR_LEVEL, Z_DEFLATED, WINDOW_BITS,
|
|
|
|
MEM_LEVEL, Z_DEFAULT_STRATEGY);
|
|
|
|
if (err != Z_OK)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
stream.next_in = in;
|
|
|
|
stream.avail_in = inlen;
|
|
|
|
stream.total_in = 0;
|
|
|
|
stream.next_out = out;
|
|
|
|
stream.avail_out = outlen;
|
|
|
|
stream.total_out = 0;
|
|
|
|
|
|
|
|
err = zlib_deflate(&stream, Z_FINISH);
|
|
|
|
if (err != Z_STREAM_END)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
err = zlib_deflateEnd(&stream);
|
|
|
|
if (err != Z_OK)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
if (stream.total_out >= stream.total_in)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
ret = stream.total_out;
|
|
|
|
error:
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2013-08-16 14:53:28 -06:00
|
|
|
/* Derived from logfs_uncompress */
|
2016-02-18 07:04:22 -07:00
|
|
|
static int decompress_zlib(void *in, void *out, size_t inlen, size_t outlen)
|
2013-08-16 14:53:28 -06:00
|
|
|
{
|
|
|
|
int err, ret;
|
|
|
|
|
|
|
|
ret = -EIO;
|
2013-09-11 11:58:03 -06:00
|
|
|
err = zlib_inflateInit2(&stream, WINDOW_BITS);
|
2013-08-16 14:53:28 -06:00
|
|
|
if (err != Z_OK)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
stream.next_in = in;
|
|
|
|
stream.avail_in = inlen;
|
|
|
|
stream.total_in = 0;
|
|
|
|
stream.next_out = out;
|
|
|
|
stream.avail_out = outlen;
|
|
|
|
stream.total_out = 0;
|
|
|
|
|
|
|
|
err = zlib_inflate(&stream, Z_FINISH);
|
|
|
|
if (err != Z_STREAM_END)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
err = zlib_inflateEnd(&stream);
|
|
|
|
if (err != Z_OK)
|
|
|
|
goto error;
|
|
|
|
|
|
|
|
ret = stream.total_out;
|
|
|
|
error:
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2016-02-18 07:04:22 -07:00
|
|
|
static void allocate_zlib(void)
|
2013-08-16 14:53:10 -06:00
|
|
|
{
|
|
|
|
size_t size;
|
2013-09-11 11:57:41 -06:00
|
|
|
size_t cmpr;
|
|
|
|
|
|
|
|
switch (psinfo->bufsize) {
|
|
|
|
/* buffer range for efivars */
|
|
|
|
case 1000 ... 2000:
|
|
|
|
cmpr = 56;
|
|
|
|
break;
|
|
|
|
case 2001 ... 3000:
|
|
|
|
cmpr = 54;
|
|
|
|
break;
|
|
|
|
case 3001 ... 3999:
|
|
|
|
cmpr = 52;
|
|
|
|
break;
|
|
|
|
/* buffer range for nvram, erst */
|
|
|
|
case 4000 ... 10000:
|
|
|
|
cmpr = 45;
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
cmpr = 60;
|
|
|
|
break;
|
|
|
|
}
|
2013-08-16 14:53:10 -06:00
|
|
|
|
2013-09-11 11:57:41 -06:00
|
|
|
big_oops_buf_sz = (psinfo->bufsize * 100) / cmpr;
|
2013-08-16 14:53:10 -06:00
|
|
|
big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
|
|
|
|
if (big_oops_buf) {
|
|
|
|
size = max(zlib_deflate_workspacesize(WINDOW_BITS, MEM_LEVEL),
|
|
|
|
zlib_inflate_workspacesize());
|
|
|
|
stream.workspace = kmalloc(size, GFP_KERNEL);
|
|
|
|
if (!stream.workspace) {
|
2014-06-06 15:37:31 -06:00
|
|
|
pr_err("No memory for compression workspace; skipping compression\n");
|
2013-08-16 14:53:10 -06:00
|
|
|
kfree(big_oops_buf);
|
|
|
|
big_oops_buf = NULL;
|
|
|
|
}
|
|
|
|
} else {
|
2014-06-06 15:37:31 -06:00
|
|
|
pr_err("No memory for uncompressed data; skipping compression\n");
|
2013-08-16 14:53:10 -06:00
|
|
|
stream.workspace = NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
}
|
|
|
|
|
2016-02-18 07:04:22 -07:00
|
|
|
static void free_zlib(void)
|
2015-10-20 01:39:03 -06:00
|
|
|
{
|
|
|
|
kfree(stream.workspace);
|
|
|
|
stream.workspace = NULL;
|
|
|
|
kfree(big_oops_buf);
|
|
|
|
big_oops_buf = NULL;
|
2016-02-18 07:04:22 -07:00
|
|
|
big_oops_buf_sz = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct pstore_zbackend backend_zlib = {
|
|
|
|
.compress = compress_zlib,
|
|
|
|
.decompress = decompress_zlib,
|
|
|
|
.allocate = allocate_zlib,
|
|
|
|
.free = free_zlib,
|
|
|
|
.name = "zlib",
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifdef CONFIG_PSTORE_LZO_COMPRESS
|
|
|
|
static int compress_lzo(const void *in, void *out, size_t inlen, size_t outlen)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = lzo1x_1_compress(in, inlen, out, &outlen, workspace);
|
|
|
|
if (ret != LZO_E_OK) {
|
|
|
|
pr_err("lzo_compress error, ret = %d!\n", ret);
|
|
|
|
return -EIO;
|
|
|
|
}
|
|
|
|
|
|
|
|
return outlen;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int decompress_lzo(void *in, void *out, size_t inlen, size_t outlen)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = lzo1x_decompress_safe(in, inlen, out, &outlen);
|
|
|
|
if (ret != LZO_E_OK) {
|
|
|
|
pr_err("lzo_decompress error, ret = %d!\n", ret);
|
|
|
|
return -EIO;
|
|
|
|
}
|
|
|
|
|
|
|
|
return outlen;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void allocate_lzo(void)
|
|
|
|
{
|
|
|
|
big_oops_buf_sz = lzo1x_worst_compress(psinfo->bufsize);
|
|
|
|
big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
|
|
|
|
if (big_oops_buf) {
|
|
|
|
workspace = kmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
|
|
|
|
if (!workspace) {
|
|
|
|
pr_err("No memory for compression workspace; skipping compression\n");
|
|
|
|
kfree(big_oops_buf);
|
|
|
|
big_oops_buf = NULL;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
pr_err("No memory for uncompressed data; skipping compression\n");
|
|
|
|
workspace = NULL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void free_lzo(void)
|
|
|
|
{
|
|
|
|
kfree(workspace);
|
|
|
|
kfree(big_oops_buf);
|
|
|
|
big_oops_buf = NULL;
|
|
|
|
big_oops_buf_sz = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct pstore_zbackend backend_lzo = {
|
|
|
|
.compress = compress_lzo,
|
|
|
|
.decompress = decompress_lzo,
|
|
|
|
.allocate = allocate_lzo,
|
|
|
|
.free = free_lzo,
|
|
|
|
.name = "lzo",
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifdef CONFIG_PSTORE_LZ4_COMPRESS
|
|
|
|
static int compress_lz4(const void *in, void *out, size_t inlen, size_t outlen)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = lz4_compress(in, inlen, out, &outlen, workspace);
|
|
|
|
if (ret) {
|
|
|
|
pr_err("lz4_compress error, ret = %d!\n", ret);
|
|
|
|
return -EIO;
|
|
|
|
}
|
|
|
|
|
|
|
|
return outlen;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int decompress_lz4(void *in, void *out, size_t inlen, size_t outlen)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = lz4_decompress_unknownoutputsize(in, inlen, out, &outlen);
|
|
|
|
if (ret) {
|
|
|
|
pr_err("lz4_decompress error, ret = %d!\n", ret);
|
|
|
|
return -EIO;
|
|
|
|
}
|
|
|
|
|
|
|
|
return outlen;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void allocate_lz4(void)
|
|
|
|
{
|
|
|
|
big_oops_buf_sz = lz4_compressbound(psinfo->bufsize);
|
|
|
|
big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
|
|
|
|
if (big_oops_buf) {
|
|
|
|
workspace = kmalloc(LZ4_MEM_COMPRESS, GFP_KERNEL);
|
|
|
|
if (!workspace) {
|
|
|
|
pr_err("No memory for compression workspace; skipping compression\n");
|
|
|
|
kfree(big_oops_buf);
|
|
|
|
big_oops_buf = NULL;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
pr_err("No memory for uncompressed data; skipping compression\n");
|
|
|
|
workspace = NULL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void free_lz4(void)
|
|
|
|
{
|
|
|
|
kfree(workspace);
|
|
|
|
kfree(big_oops_buf);
|
|
|
|
big_oops_buf = NULL;
|
|
|
|
big_oops_buf_sz = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct pstore_zbackend backend_lz4 = {
|
|
|
|
.compress = compress_lz4,
|
|
|
|
.decompress = decompress_lz4,
|
|
|
|
.allocate = allocate_lz4,
|
|
|
|
.free = free_lz4,
|
|
|
|
.name = "lz4",
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
|
|
|
static struct pstore_zbackend *zbackend =
|
|
|
|
#if defined(CONFIG_PSTORE_ZLIB_COMPRESS)
|
|
|
|
&backend_zlib;
|
|
|
|
#elif defined(CONFIG_PSTORE_LZO_COMPRESS)
|
|
|
|
&backend_lzo;
|
|
|
|
#elif defined(CONFIG_PSTORE_LZ4_COMPRESS)
|
|
|
|
&backend_lz4;
|
|
|
|
#else
|
|
|
|
NULL;
|
|
|
|
#endif
|
|
|
|
|
|
|
|
static int pstore_compress(const void *in, void *out,
|
|
|
|
size_t inlen, size_t outlen)
|
|
|
|
{
|
|
|
|
if (zbackend)
|
|
|
|
return zbackend->compress(in, out, inlen, outlen);
|
|
|
|
else
|
|
|
|
return -EIO;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int pstore_decompress(void *in, void *out, size_t inlen, size_t outlen)
|
|
|
|
{
|
|
|
|
if (zbackend)
|
|
|
|
return zbackend->decompress(in, out, inlen, outlen);
|
|
|
|
else
|
|
|
|
return -EIO;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void allocate_buf_for_compression(void)
|
|
|
|
{
|
|
|
|
if (zbackend) {
|
|
|
|
pr_info("using %s compression\n", zbackend->name);
|
|
|
|
zbackend->allocate();
|
|
|
|
} else {
|
|
|
|
pr_err("allocate compression buffer error!\n");
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void free_buf_for_compression(void)
|
|
|
|
{
|
|
|
|
if (zbackend)
|
|
|
|
zbackend->free();
|
|
|
|
else
|
|
|
|
pr_err("free compression buffer error!\n");
|
2015-10-20 01:39:03 -06:00
|
|
|
}
|
|
|
|
|
2013-08-16 14:53:10 -06:00
|
|
|
/*
|
|
|
|
* Called when compression fails, since the printk buffer
|
|
|
|
* would be fetched for compression calling it again when
|
|
|
|
* compression fails would have moved the iterator of
|
|
|
|
* printk buffer which results in fetching old contents.
|
|
|
|
* Copy the recent messages from big_oops_buf to psinfo->buf
|
|
|
|
*/
|
|
|
|
static size_t copy_kmsg_to_buffer(int hsize, size_t len)
|
|
|
|
{
|
|
|
|
size_t total_len;
|
|
|
|
size_t diff;
|
|
|
|
|
|
|
|
total_len = hsize + len;
|
|
|
|
|
|
|
|
if (total_len > psinfo->bufsize) {
|
|
|
|
diff = total_len - psinfo->bufsize + hsize;
|
|
|
|
memcpy(psinfo->buf, big_oops_buf, hsize);
|
|
|
|
memcpy(psinfo->buf + hsize, big_oops_buf + diff,
|
|
|
|
psinfo->bufsize - hsize);
|
|
|
|
total_len = psinfo->bufsize;
|
|
|
|
} else
|
|
|
|
memcpy(psinfo->buf, big_oops_buf, total_len);
|
|
|
|
|
|
|
|
return total_len;
|
|
|
|
}
|
|
|
|
|
2010-12-28 15:25:21 -07:00
|
|
|
/*
|
|
|
|
* callback from kmsg_dump. (s2,l2) has the most recently
|
|
|
|
* written bytes, older bytes are in (s1,l1). Save as much
|
|
|
|
* as we can from the end of the buffer.
|
|
|
|
*/
|
|
|
|
static void pstore_dump(struct kmsg_dumper *dumper,
|
2012-06-15 06:07:51 -06:00
|
|
|
enum kmsg_dump_reason reason)
|
2010-12-28 15:25:21 -07:00
|
|
|
{
|
2012-06-15 06:07:51 -06:00
|
|
|
unsigned long total = 0;
|
2012-03-16 16:36:59 -06:00
|
|
|
const char *why;
|
2010-12-28 15:25:21 -07:00
|
|
|
u64 id;
|
2011-07-21 14:57:54 -06:00
|
|
|
unsigned int part = 1;
|
2011-08-12 11:54:51 -06:00
|
|
|
unsigned long flags = 0;
|
2016-05-18 06:00:05 -06:00
|
|
|
int is_locked;
|
2012-06-15 06:07:51 -06:00
|
|
|
int ret;
|
2010-12-28 15:25:21 -07:00
|
|
|
|
2012-03-16 16:36:59 -06:00
|
|
|
why = get_reason_str(reason);
|
2011-03-22 17:01:49 -06:00
|
|
|
|
pstore: Avoid deadlock in panic and emergency-restart path
[Issue]
When pstore is in panic and emergency-restart paths, it may be blocked
in those paths because it simply takes spin_lock.
This is an example scenario which pstore may hang up in a panic path:
- cpuA grabs psinfo->buf_lock
- cpuB panics and calls smp_send_stop
- smp_send_stop sends IRQ to cpuA
- after 1 second, cpuB gives up on cpuA and sends an NMI instead
- cpuA is now in an NMI handler while still holding buf_lock
- cpuB is deadlocked
This case may happen if a firmware has a bug and
cpuA is stuck talking with it more than one second.
Also, this is a similar scenario in an emergency-restart path:
- cpuA grabs psinfo->buf_lock and stucks in a firmware
- cpuB kicks emergency-restart via either sysrq-b or hangcheck timer.
And then, cpuB is deadlocked by taking psinfo->buf_lock again.
[Solution]
This patch avoids the deadlocking issues in both panic and emergency_restart
paths by introducing a function, is_non_blocking_path(), to check if a cpu
can be blocked in current path.
With this patch, pstore is not blocked even if another cpu has
taken a spin_lock, in those paths by changing from spin_lock_irqsave
to spin_trylock_irqsave.
In addition, according to a comment of emergency_restart() in kernel/sys.c,
spin_lock shouldn't be taken in an emergency_restart path to avoid
deadlock. This patch fits the comment below.
<snip>
/**
* emergency_restart - reboot the system
*
* Without shutting down any hardware or taking any locks
* reboot the system. This is called when we know we are in
* trouble so this is our best effort to reboot. This is
* safe to call in interrupt context.
*/
void emergency_restart(void)
<snip>
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-01-11 11:09:41 -07:00
|
|
|
if (pstore_cannot_block_path(reason)) {
|
|
|
|
is_locked = spin_trylock_irqsave(&psinfo->buf_lock, flags);
|
|
|
|
if (!is_locked) {
|
|
|
|
pr_err("pstore dump routine blocked in %s path, may corrupt error record\n"
|
|
|
|
, in_nmi() ? "NMI" : why);
|
|
|
|
}
|
2016-05-18 06:00:05 -06:00
|
|
|
} else {
|
2011-08-12 11:54:51 -06:00
|
|
|
spin_lock_irqsave(&psinfo->buf_lock, flags);
|
2016-05-18 06:00:05 -06:00
|
|
|
is_locked = 1;
|
|
|
|
}
|
2010-12-28 15:25:21 -07:00
|
|
|
oopscount++;
|
|
|
|
while (total < kmsg_bytes) {
|
2012-06-15 06:07:51 -06:00
|
|
|
char *dst;
|
|
|
|
unsigned long size;
|
|
|
|
int hsize;
|
2013-08-16 14:53:10 -06:00
|
|
|
int zipped_len = -1;
|
2012-06-15 06:07:51 -06:00
|
|
|
size_t len;
|
2016-05-18 06:00:06 -06:00
|
|
|
bool compressed = false;
|
2013-08-16 14:53:10 -06:00
|
|
|
size_t total_len;
|
2012-06-15 06:07:51 -06:00
|
|
|
|
2015-05-21 10:26:19 -06:00
|
|
|
if (big_oops_buf && is_locked) {
|
2013-08-16 14:53:10 -06:00
|
|
|
dst = big_oops_buf;
|
2016-05-18 06:00:06 -06:00
|
|
|
size = big_oops_buf_sz;
|
|
|
|
} else {
|
|
|
|
dst = psinfo->buf;
|
|
|
|
size = psinfo->bufsize;
|
|
|
|
}
|
|
|
|
|
|
|
|
hsize = sprintf(dst, "%s#%d Part%u\n", why, oopscount, part);
|
|
|
|
size -= hsize;
|
2010-12-28 15:25:21 -07:00
|
|
|
|
2016-05-18 06:00:06 -06:00
|
|
|
if (!kmsg_dump_get_buffer(dumper, true, dst + hsize,
|
|
|
|
size, &len))
|
|
|
|
break;
|
2013-08-16 14:53:10 -06:00
|
|
|
|
2016-05-18 06:00:06 -06:00
|
|
|
if (big_oops_buf && is_locked) {
|
2013-08-16 14:53:10 -06:00
|
|
|
zipped_len = pstore_compress(dst, psinfo->buf,
|
|
|
|
hsize + len, psinfo->bufsize);
|
|
|
|
|
|
|
|
if (zipped_len > 0) {
|
|
|
|
compressed = true;
|
|
|
|
total_len = zipped_len;
|
|
|
|
} else {
|
|
|
|
total_len = copy_kmsg_to_buffer(hsize, len);
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
total_len = hsize + len;
|
|
|
|
}
|
2010-12-28 15:25:21 -07:00
|
|
|
|
2011-11-17 14:13:29 -07:00
|
|
|
ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part,
|
2013-08-16 14:53:10 -06:00
|
|
|
oopscount, compressed, total_len, psinfo);
|
2011-10-12 10:17:24 -06:00
|
|
|
if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
|
2011-08-11 16:14:39 -06:00
|
|
|
pstore_new_entry = 1;
|
2012-06-15 06:07:51 -06:00
|
|
|
|
2013-08-16 14:53:10 -06:00
|
|
|
total += total_len;
|
2011-07-21 14:57:53 -06:00
|
|
|
part++;
|
2010-12-28 15:25:21 -07:00
|
|
|
}
|
2016-05-18 06:00:05 -06:00
|
|
|
if (is_locked)
|
2011-08-12 11:54:51 -06:00
|
|
|
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
|
2010-12-28 15:25:21 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
static struct kmsg_dumper pstore_dumper = {
|
|
|
|
.dump = pstore_dump,
|
|
|
|
};
|
|
|
|
|
2015-10-31 09:23:15 -06:00
|
|
|
/*
|
|
|
|
* Register with kmsg_dump to save last part of console log on panic.
|
|
|
|
*/
|
2015-10-20 01:39:02 -06:00
|
|
|
static void pstore_register_kmsg(void)
|
|
|
|
{
|
|
|
|
kmsg_dump_register(&pstore_dumper);
|
|
|
|
}
|
|
|
|
|
2015-10-20 01:39:03 -06:00
|
|
|
static void pstore_unregister_kmsg(void)
|
|
|
|
{
|
|
|
|
kmsg_dump_unregister(&pstore_dumper);
|
|
|
|
}
|
|
|
|
|
2012-05-26 07:20:19 -06:00
|
|
|
#ifdef CONFIG_PSTORE_CONSOLE
|
|
|
|
static void pstore_console_write(struct console *con, const char *s, unsigned c)
|
|
|
|
{
|
|
|
|
const char *e = s + c;
|
|
|
|
|
|
|
|
while (s < e) {
|
|
|
|
unsigned long flags;
|
2012-11-14 04:49:53 -07:00
|
|
|
u64 id;
|
2012-05-26 07:20:19 -06:00
|
|
|
|
|
|
|
if (c > psinfo->bufsize)
|
|
|
|
c = psinfo->bufsize;
|
2012-09-17 11:43:44 -06:00
|
|
|
|
|
|
|
if (oops_in_progress) {
|
|
|
|
if (!spin_trylock_irqsave(&psinfo->buf_lock, flags))
|
|
|
|
break;
|
|
|
|
} else {
|
|
|
|
spin_lock_irqsave(&psinfo->buf_lock, flags);
|
|
|
|
}
|
2012-05-26 07:20:19 -06:00
|
|
|
memcpy(psinfo->buf, s, c);
|
2013-06-27 02:32:56 -06:00
|
|
|
psinfo->write(PSTORE_TYPE_CONSOLE, 0, &id, 0, 0, 0, c, psinfo);
|
2012-05-26 07:20:19 -06:00
|
|
|
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
|
|
|
|
s += c;
|
|
|
|
c = e - s;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct console pstore_console = {
|
|
|
|
.name = "pstore",
|
|
|
|
.write = pstore_console_write,
|
|
|
|
.flags = CON_PRINTBUFFER | CON_ENABLED | CON_ANYTIME,
|
|
|
|
.index = -1,
|
|
|
|
};
|
|
|
|
|
|
|
|
static void pstore_register_console(void)
|
|
|
|
{
|
|
|
|
register_console(&pstore_console);
|
|
|
|
}
|
2015-10-20 01:39:03 -06:00
|
|
|
|
|
|
|
static void pstore_unregister_console(void)
|
|
|
|
{
|
|
|
|
unregister_console(&pstore_console);
|
|
|
|
}
|
2012-05-26 07:20:19 -06:00
|
|
|
#else
|
|
|
|
static void pstore_register_console(void) {}
|
2015-10-20 01:39:03 -06:00
|
|
|
static void pstore_unregister_console(void) {}
|
2012-05-26 07:20:19 -06:00
|
|
|
#endif
|
|
|
|
|
2012-07-09 18:10:40 -06:00
|
|
|
static int pstore_write_compat(enum pstore_type_id type,
|
|
|
|
enum kmsg_dump_reason reason,
|
efi_pstore: Add a sequence counter to a variable name
[Issue]
Currently, a variable name, which identifies each entry, consists of type, id and ctime.
But if multiple events happens in a short time, a second/third event may fail to log because
efi_pstore can't distinguish each event with current variable name.
[Solution]
A reasonable way to identify all events precisely is introducing a sequence counter to
the variable name.
The sequence counter has already supported in a pstore layer with "oopscount".
So, this patch adds it to a variable name.
Also, it is passed to read/erase callbacks of platform drivers in accordance with
the modification of the variable name.
<before applying this patch>
a variable name of first event: dump-type0-1-12345678
a variable name of second event: dump-type0-1-12345678
type:0
id:1
ctime:12345678
If multiple events happen in a short time, efi_pstore can't distinguish them because
variable names are same among them.
<after applying this patch>
it can be distinguishable by adding a sequence counter as follows.
a variable name of first event: dump-type0-1-1-12345678
a variable name of Second event: dump-type0-1-2-12345678
type:0
id:1
sequence counter: 1(first event), 2(second event)
ctime:12345678
In case of a write callback executed in pstore_console_write(), "0" is added to
an argument of the write callback because it just logs all kernel messages and
doesn't need to care about multiple events.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2012-11-26 17:07:44 -07:00
|
|
|
u64 *id, unsigned int part, int count,
|
2013-08-16 14:52:47 -06:00
|
|
|
bool compressed, size_t size,
|
2013-06-27 02:32:56 -06:00
|
|
|
struct pstore_info *psi)
|
2012-07-09 18:10:40 -06:00
|
|
|
{
|
2013-08-16 14:52:47 -06:00
|
|
|
return psi->write_buf(type, reason, id, part, psinfo->buf, compressed,
|
2013-06-27 02:32:56 -06:00
|
|
|
size, psi);
|
2012-07-09 18:10:40 -06:00
|
|
|
}
|
|
|
|
|
2010-12-28 15:25:21 -07:00
|
|
|
/*
|
|
|
|
* platform specific persistent storage driver registers with
|
|
|
|
* us here. If pstore is already mounted, call the platform
|
|
|
|
* read function right away to populate the file system. If not
|
|
|
|
* then the pstore mount code will call us later to fill out
|
|
|
|
* the file system.
|
|
|
|
*/
|
|
|
|
int pstore_register(struct pstore_info *psi)
|
|
|
|
{
|
|
|
|
struct module *owner = psi->owner;
|
|
|
|
|
2013-06-28 15:11:33 -06:00
|
|
|
if (backend && strcmp(backend, psi->name))
|
|
|
|
return -EPERM;
|
|
|
|
|
2010-12-28 15:25:21 -07:00
|
|
|
spin_lock(&pstore_lock);
|
|
|
|
if (psinfo) {
|
|
|
|
spin_unlock(&pstore_lock);
|
|
|
|
return -EBUSY;
|
|
|
|
}
|
2011-07-21 14:57:55 -06:00
|
|
|
|
2012-07-09 18:10:40 -06:00
|
|
|
if (!psi->write)
|
|
|
|
psi->write = pstore_write_compat;
|
2010-12-28 15:25:21 -07:00
|
|
|
psinfo = psi;
|
2011-11-17 13:58:07 -07:00
|
|
|
mutex_init(&psinfo->read_mutex);
|
2010-12-28 15:25:21 -07:00
|
|
|
spin_unlock(&pstore_lock);
|
|
|
|
|
|
|
|
if (owner && !try_module_get(owner)) {
|
|
|
|
psinfo = NULL;
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
|
2013-08-16 14:53:10 -06:00
|
|
|
allocate_buf_for_compression();
|
|
|
|
|
2010-12-28 15:25:21 -07:00
|
|
|
if (pstore_is_mounted())
|
2011-08-11 16:14:39 -06:00
|
|
|
pstore_get_records(0);
|
2010-12-28 15:25:21 -07:00
|
|
|
|
2015-10-20 01:39:02 -06:00
|
|
|
pstore_register_kmsg();
|
2013-12-18 16:17:10 -07:00
|
|
|
|
|
|
|
if ((psi->flags & PSTORE_FLAGS_FRAGILE) == 0) {
|
|
|
|
pstore_register_console();
|
|
|
|
pstore_register_ftrace();
|
2015-01-16 17:01:10 -07:00
|
|
|
pstore_register_pmsg();
|
2013-12-18 16:17:10 -07:00
|
|
|
}
|
2010-12-28 15:25:21 -07:00
|
|
|
|
2012-05-26 07:20:28 -06:00
|
|
|
if (pstore_update_ms >= 0) {
|
|
|
|
pstore_timer.expires = jiffies +
|
|
|
|
msecs_to_jiffies(pstore_update_ms);
|
|
|
|
add_timer(&pstore_timer);
|
|
|
|
}
|
2011-08-11 16:14:39 -06:00
|
|
|
|
2015-05-21 10:34:22 -06:00
|
|
|
/*
|
|
|
|
* Update the module parameter backend, so it is visible
|
|
|
|
* through /sys/module/pstore/parameters/backend
|
|
|
|
*/
|
|
|
|
backend = psi->name;
|
|
|
|
|
2015-10-20 01:39:03 -06:00
|
|
|
module_put(owner);
|
|
|
|
|
2014-06-06 15:37:31 -06:00
|
|
|
pr_info("Registered %s as persistent store backend\n", psi->name);
|
2013-06-28 15:11:33 -06:00
|
|
|
|
2010-12-28 15:25:21 -07:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(pstore_register);
|
|
|
|
|
2015-10-20 01:39:03 -06:00
|
|
|
void pstore_unregister(struct pstore_info *psi)
|
|
|
|
{
|
2016-05-19 08:59:03 -06:00
|
|
|
if ((psi->flags & PSTORE_FLAGS_FRAGILE) == 0) {
|
|
|
|
pstore_unregister_pmsg();
|
|
|
|
pstore_unregister_ftrace();
|
|
|
|
pstore_unregister_console();
|
|
|
|
}
|
2015-10-20 01:39:03 -06:00
|
|
|
pstore_unregister_kmsg();
|
|
|
|
|
|
|
|
free_buf_for_compression();
|
|
|
|
|
|
|
|
psinfo = NULL;
|
|
|
|
backend = NULL;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(pstore_unregister);
|
|
|
|
|
2010-12-28 15:25:21 -07:00
|
|
|
/*
|
2011-08-11 16:14:39 -06:00
|
|
|
* Read all the records from the persistent store. Create
|
|
|
|
* files in our filesystem. Don't warn about -EEXIST errors
|
|
|
|
* when we are re-scanning the backing store looking to add new
|
|
|
|
* error records.
|
2010-12-28 15:25:21 -07:00
|
|
|
*/
|
2011-08-11 16:14:39 -06:00
|
|
|
void pstore_get_records(int quiet)
|
2010-12-28 15:25:21 -07:00
|
|
|
{
|
|
|
|
struct pstore_info *psi = psinfo;
|
2011-11-17 13:58:07 -07:00
|
|
|
char *buf = NULL;
|
2011-05-16 11:58:57 -06:00
|
|
|
ssize_t size;
|
2010-12-28 15:25:21 -07:00
|
|
|
u64 id;
|
efi_pstore: Add a sequence counter to a variable name
[Issue]
Currently, a variable name, which identifies each entry, consists of type, id and ctime.
But if multiple events happens in a short time, a second/third event may fail to log because
efi_pstore can't distinguish each event with current variable name.
[Solution]
A reasonable way to identify all events precisely is introducing a sequence counter to
the variable name.
The sequence counter has already supported in a pstore layer with "oopscount".
So, this patch adds it to a variable name.
Also, it is passed to read/erase callbacks of platform drivers in accordance with
the modification of the variable name.
<before applying this patch>
a variable name of first event: dump-type0-1-12345678
a variable name of second event: dump-type0-1-12345678
type:0
id:1
ctime:12345678
If multiple events happen in a short time, efi_pstore can't distinguish them because
variable names are same among them.
<after applying this patch>
it can be distinguishable by adding a sequence counter as follows.
a variable name of first event: dump-type0-1-1-12345678
a variable name of Second event: dump-type0-1-2-12345678
type:0
id:1
sequence counter: 1(first event), 2(second event)
ctime:12345678
In case of a write callback executed in pstore_console_write(), "0" is added to
an argument of the write callback because it just logs all kernel messages and
doesn't need to care about multiple events.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2012-11-26 17:07:44 -07:00
|
|
|
int count;
|
2010-12-28 15:25:21 -07:00
|
|
|
enum pstore_type_id type;
|
|
|
|
struct timespec time;
|
2011-05-16 12:00:27 -06:00
|
|
|
int failed = 0, rc;
|
2013-08-16 14:53:19 -06:00
|
|
|
bool compressed;
|
2013-08-16 14:53:28 -06:00
|
|
|
int unzipped_len = -1;
|
2016-02-18 07:04:22 -07:00
|
|
|
ssize_t ecc_notice_size = 0;
|
2010-12-28 15:25:21 -07:00
|
|
|
|
|
|
|
if (!psi)
|
|
|
|
return;
|
|
|
|
|
2011-11-17 13:58:07 -07:00
|
|
|
mutex_lock(&psi->read_mutex);
|
2011-11-18 14:49:00 -07:00
|
|
|
if (psi->open && psi->open(psi))
|
2011-05-16 12:00:27 -06:00
|
|
|
goto out;
|
|
|
|
|
2013-08-16 14:53:19 -06:00
|
|
|
while ((size = psi->read(&id, &type, &count, &time, &buf, &compressed,
|
2016-02-18 07:04:22 -07:00
|
|
|
&ecc_notice_size, psi)) > 0) {
|
2013-08-16 14:53:28 -06:00
|
|
|
if (compressed && (type == PSTORE_TYPE_DMESG)) {
|
|
|
|
if (big_oops_buf)
|
|
|
|
unzipped_len = pstore_decompress(buf,
|
|
|
|
big_oops_buf, size,
|
|
|
|
big_oops_buf_sz);
|
|
|
|
|
|
|
|
if (unzipped_len > 0) {
|
2016-02-18 07:04:22 -07:00
|
|
|
if (ecc_notice_size)
|
|
|
|
memcpy(big_oops_buf + unzipped_len,
|
|
|
|
buf + size, ecc_notice_size);
|
2014-03-12 07:34:06 -06:00
|
|
|
kfree(buf);
|
2013-08-16 14:53:28 -06:00
|
|
|
buf = big_oops_buf;
|
|
|
|
size = unzipped_len;
|
2013-08-16 14:53:39 -06:00
|
|
|
compressed = false;
|
2013-08-16 14:53:28 -06:00
|
|
|
} else {
|
2014-06-06 15:37:31 -06:00
|
|
|
pr_err("decompression failed;returned %d\n",
|
|
|
|
unzipped_len);
|
2013-08-16 14:53:39 -06:00
|
|
|
compressed = true;
|
2013-08-16 14:53:28 -06:00
|
|
|
}
|
|
|
|
}
|
efi_pstore: Add a sequence counter to a variable name
[Issue]
Currently, a variable name, which identifies each entry, consists of type, id and ctime.
But if multiple events happens in a short time, a second/third event may fail to log because
efi_pstore can't distinguish each event with current variable name.
[Solution]
A reasonable way to identify all events precisely is introducing a sequence counter to
the variable name.
The sequence counter has already supported in a pstore layer with "oopscount".
So, this patch adds it to a variable name.
Also, it is passed to read/erase callbacks of platform drivers in accordance with
the modification of the variable name.
<before applying this patch>
a variable name of first event: dump-type0-1-12345678
a variable name of second event: dump-type0-1-12345678
type:0
id:1
ctime:12345678
If multiple events happen in a short time, efi_pstore can't distinguish them because
variable names are same among them.
<after applying this patch>
it can be distinguishable by adding a sequence counter as follows.
a variable name of first event: dump-type0-1-1-12345678
a variable name of Second event: dump-type0-1-2-12345678
type:0
id:1
sequence counter: 1(first event), 2(second event)
ctime:12345678
In case of a write callback executed in pstore_console_write(), "0" is added to
an argument of the write callback because it just logs all kernel messages and
doesn't need to care about multiple events.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2012-11-26 17:07:44 -07:00
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rc = pstore_mkfile(type, psi->name, id, count, buf,
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2016-02-18 07:04:22 -07:00
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compressed, size + ecc_notice_size,
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time, psi);
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2013-08-16 14:53:28 -06:00
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if (unzipped_len < 0) {
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/* Free buffer other than big oops */
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kfree(buf);
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buf = NULL;
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} else
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unzipped_len = -1;
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2011-08-11 16:14:39 -06:00
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if (rc && (rc != -EEXIST || !quiet))
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2010-12-28 15:25:21 -07:00
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failed++;
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}
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2011-11-18 14:49:00 -07:00
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if (psi->close)
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psi->close(psi);
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2011-05-16 12:00:27 -06:00
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out:
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2011-11-17 13:58:07 -07:00
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mutex_unlock(&psi->read_mutex);
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2010-12-28 15:25:21 -07:00
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if (failed)
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2014-06-06 15:37:31 -06:00
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pr_warn("failed to load %d record(s) from '%s'\n",
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failed, psi->name);
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2010-12-28 15:25:21 -07:00
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}
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2011-08-11 16:14:39 -06:00
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static void pstore_dowork(struct work_struct *work)
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{
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pstore_get_records(1);
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}
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static void pstore_timefunc(unsigned long dummy)
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{
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if (pstore_new_entry) {
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pstore_new_entry = 0;
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schedule_work(&pstore_work);
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}
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2012-05-26 07:20:28 -06:00
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mod_timer(&pstore_timer, jiffies + msecs_to_jiffies(pstore_update_ms));
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2011-08-11 16:14:39 -06:00
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}
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2011-07-21 14:57:55 -06:00
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module_param(backend, charp, 0444);
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MODULE_PARM_DESC(backend, "Pstore backend to use");
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