Revision 85bd839983778fcd0c1c043327b14a046e979b39 authored by Gu Zheng on 10 June 2015, 18:14:43 UTC, committed by Linus Torvalds on 10 June 2015, 23:43:43 UTC
Izumi found the following oops when hot re-adding a node: BUG: unable to handle kernel paging request at ffffc90008963690 IP: __wake_up_bit+0x20/0x70 Oops: 0000 [#1] SMP CPU: 68 PID: 1237 Comm: rs:main Q:Reg Not tainted 4.1.0-rc5 #80 Hardware name: FUJITSU PRIMEQUEST2800E/SB, BIOS PRIMEQUEST 2000 Series BIOS Version 1.87 04/28/2015 task: ffff880838df8000 ti: ffff880017b94000 task.ti: ffff880017b94000 RIP: 0010:[<ffffffff810dff80>] [<ffffffff810dff80>] __wake_up_bit+0x20/0x70 RSP: 0018:ffff880017b97be8 EFLAGS: 00010246 RAX: ffffc90008963690 RBX: 00000000003c0000 RCX: 000000000000a4c9 RDX: 0000000000000000 RSI: ffffea101bffd500 RDI: ffffc90008963648 RBP: ffff880017b97c08 R08: 0000000002000020 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a0797c73800 R13: ffffea101bffd500 R14: 0000000000000001 R15: 00000000003c0000 FS: 00007fcc7ffff700(0000) GS:ffff880874800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90008963690 CR3: 0000000836761000 CR4: 00000000001407e0 Call Trace: unlock_page+0x6d/0x70 generic_write_end+0x53/0xb0 xfs_vm_write_end+0x29/0x80 [xfs] generic_perform_write+0x10a/0x1e0 xfs_file_buffered_aio_write+0x14d/0x3e0 [xfs] xfs_file_write_iter+0x79/0x120 [xfs] __vfs_write+0xd4/0x110 vfs_write+0xac/0x1c0 SyS_write+0x58/0xd0 system_call_fastpath+0x12/0x76 Code: 5d c3 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 45 f8 31 c0 48 8d 47 48 <48> 39 47 48 48 c7 45 e8 00 00 00 00 48 c7 45 f0 00 00 00 00 48 RIP [<ffffffff810dff80>] __wake_up_bit+0x20/0x70 RSP <ffff880017b97be8> CR2: ffffc90008963690 Reproduce method (re-add a node):: Hot-add nodeA --> remove nodeA --> hot-add nodeA (panic) This seems an use-after-free problem, and the root cause is zone->wait_table was not set to *NULL* after free it in try_offline_node. When hot re-add a node, we will reuse the pgdat of it, so does the zone struct, and when add pages to the target zone, it will init the zone first (including the wait_table) if the zone is not initialized. The judgement of zone initialized is based on zone->wait_table: static inline bool zone_is_initialized(struct zone *zone) { return !!zone->wait_table; } so if we do not set the zone->wait_table to *NULL* after free it, the memory hotplug routine will skip the init of new zone when hot re-add the node, and the wait_table still points to the freed memory, then we will access the invalid address when trying to wake up the waiting people after the i/o operation with the page is done, such as mentioned above. Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Reviewed by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 5879ae5
dtc2278.c
/*
* Copyright (C) 1996 Linus Torvalds & author (see below)
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/blkdev.h>
#include <linux/ide.h>
#include <linux/init.h>
#include <asm/io.h>
#define DRV_NAME "dtc2278"
/*
* Changing this #undef to #define may solve start up problems in some systems.
*/
#undef ALWAYS_SET_DTC2278_PIO_MODE
/*
* From: andy@cercle.cts.com (Dyan Wile)
*
* Below is a patch for DTC-2278 - alike software-programmable controllers
* The code enables the secondary IDE controller and the PIO4 (3?) timings on
* the primary (EIDE). You may probably have to enable the 32-bit support to
* get the full speed. You better get the disk interrupts disabled ( hdparm -u0
* /dev/hd.. ) for the drives connected to the EIDE interface. (I get my
* filesystem corrupted with -u1, but under heavy disk load only :-)
*
* This card is now forced to use the "serialize" feature,
* and irq-unmasking is disallowed. If io_32bit is enabled,
* it must be done for BOTH drives on each interface.
*
* This code was written for the DTC2278E, but might work with any of these:
*
* DTC2278S has only a single IDE interface.
* DTC2278D has two IDE interfaces and is otherwise identical to the S version.
* DTC2278E also has serial ports and a printer port
* DTC2278EB: has onboard BIOS, and "works like a charm" -- Kent Bradford <kent@theory.caltech.edu>
*
* There may be a fourth controller type. The S and D versions use the
* Winbond chip, and I think the E version does also.
*
*/
static void sub22 (char b, char c)
{
int i;
for(i = 0; i < 3; ++i) {
inb(0x3f6);
outb_p(b,0xb0);
inb(0x3f6);
outb_p(c,0xb4);
inb(0x3f6);
if(inb(0xb4) == c) {
outb_p(7,0xb0);
inb(0x3f6);
return; /* success */
}
}
}
static DEFINE_SPINLOCK(dtc2278_lock);
static void dtc2278_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
{
unsigned long flags;
if (drive->pio_mode >= XFER_PIO_3) {
spin_lock_irqsave(&dtc2278_lock, flags);
/*
* This enables PIO mode4 (3?) on the first interface
*/
sub22(1,0xc3);
sub22(0,0xa0);
spin_unlock_irqrestore(&dtc2278_lock, flags);
} else {
/* we don't know how to set it back again.. */
/* Actually we do - there is a data sheet available for the
Winbond but does anyone actually care */
}
}
static const struct ide_port_ops dtc2278_port_ops = {
.set_pio_mode = dtc2278_set_pio_mode,
};
static const struct ide_port_info dtc2278_port_info __initconst = {
.name = DRV_NAME,
.chipset = ide_dtc2278,
.port_ops = &dtc2278_port_ops,
.host_flags = IDE_HFLAG_SERIALIZE |
IDE_HFLAG_NO_UNMASK_IRQS |
IDE_HFLAG_IO_32BIT |
/* disallow ->io_32bit changes */
IDE_HFLAG_NO_IO_32BIT |
IDE_HFLAG_NO_DMA |
IDE_HFLAG_DTC2278,
.pio_mask = ATA_PIO4,
};
static int __init dtc2278_probe(void)
{
unsigned long flags;
local_irq_save(flags);
/*
* This enables the second interface
*/
outb_p(4,0xb0);
inb(0x3f6);
outb_p(0x20,0xb4);
inb(0x3f6);
#ifdef ALWAYS_SET_DTC2278_PIO_MODE
/*
* This enables PIO mode4 (3?) on the first interface
* and may solve start-up problems for some people.
*/
sub22(1,0xc3);
sub22(0,0xa0);
#endif
local_irq_restore(flags);
return ide_legacy_device_add(&dtc2278_port_info, 0);
}
static bool probe_dtc2278;
module_param_named(probe, probe_dtc2278, bool, 0);
MODULE_PARM_DESC(probe, "probe for DTC2278xx chipsets");
static int __init dtc2278_init(void)
{
if (probe_dtc2278 == 0)
return -ENODEV;
if (dtc2278_probe()) {
printk(KERN_ERR "dtc2278: ide interfaces already in use!\n");
return -EBUSY;
}
return 0;
}
module_init(dtc2278_init);
MODULE_AUTHOR("See Local File");
MODULE_DESCRIPTION("support of DTC-2278 VLB IDE chipsets");
MODULE_LICENSE("GPL");
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...