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
clk-efm32gg.c
/*
* Copyright (C) 2013 Pengutronix
* Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License version 2 as published by the
* Free Software Foundation.
*/
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/clk-provider.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <dt-bindings/clock/efm32-cmu.h>
#define CMU_HFPERCLKEN0 0x44
static struct clk *clk[37];
static struct clk_onecell_data clk_data = {
.clks = clk,
.clk_num = ARRAY_SIZE(clk),
};
static void __init efm32gg_cmu_init(struct device_node *np)
{
int i;
void __iomem *base;
for (i = 0; i < ARRAY_SIZE(clk); ++i)
clk[i] = ERR_PTR(-ENOENT);
base = of_iomap(np, 0);
if (!base) {
pr_warn("Failed to map address range for efm32gg,cmu node\n");
return;
}
clk[clk_HFXO] = clk_register_fixed_rate(NULL, "HFXO", NULL,
CLK_IS_ROOT, 48000000);
clk[clk_HFPERCLKUSART0] = clk_register_gate(NULL, "HFPERCLK.USART0",
"HFXO", 0, base + CMU_HFPERCLKEN0, 0, 0, NULL);
clk[clk_HFPERCLKUSART1] = clk_register_gate(NULL, "HFPERCLK.USART1",
"HFXO", 0, base + CMU_HFPERCLKEN0, 1, 0, NULL);
clk[clk_HFPERCLKUSART2] = clk_register_gate(NULL, "HFPERCLK.USART2",
"HFXO", 0, base + CMU_HFPERCLKEN0, 2, 0, NULL);
clk[clk_HFPERCLKUART0] = clk_register_gate(NULL, "HFPERCLK.UART0",
"HFXO", 0, base + CMU_HFPERCLKEN0, 3, 0, NULL);
clk[clk_HFPERCLKUART1] = clk_register_gate(NULL, "HFPERCLK.UART1",
"HFXO", 0, base + CMU_HFPERCLKEN0, 4, 0, NULL);
clk[clk_HFPERCLKTIMER0] = clk_register_gate(NULL, "HFPERCLK.TIMER0",
"HFXO", 0, base + CMU_HFPERCLKEN0, 5, 0, NULL);
clk[clk_HFPERCLKTIMER1] = clk_register_gate(NULL, "HFPERCLK.TIMER1",
"HFXO", 0, base + CMU_HFPERCLKEN0, 6, 0, NULL);
clk[clk_HFPERCLKTIMER2] = clk_register_gate(NULL, "HFPERCLK.TIMER2",
"HFXO", 0, base + CMU_HFPERCLKEN0, 7, 0, NULL);
clk[clk_HFPERCLKTIMER3] = clk_register_gate(NULL, "HFPERCLK.TIMER3",
"HFXO", 0, base + CMU_HFPERCLKEN0, 8, 0, NULL);
clk[clk_HFPERCLKACMP0] = clk_register_gate(NULL, "HFPERCLK.ACMP0",
"HFXO", 0, base + CMU_HFPERCLKEN0, 9, 0, NULL);
clk[clk_HFPERCLKACMP1] = clk_register_gate(NULL, "HFPERCLK.ACMP1",
"HFXO", 0, base + CMU_HFPERCLKEN0, 10, 0, NULL);
clk[clk_HFPERCLKI2C0] = clk_register_gate(NULL, "HFPERCLK.I2C0",
"HFXO", 0, base + CMU_HFPERCLKEN0, 11, 0, NULL);
clk[clk_HFPERCLKI2C1] = clk_register_gate(NULL, "HFPERCLK.I2C1",
"HFXO", 0, base + CMU_HFPERCLKEN0, 12, 0, NULL);
clk[clk_HFPERCLKGPIO] = clk_register_gate(NULL, "HFPERCLK.GPIO",
"HFXO", 0, base + CMU_HFPERCLKEN0, 13, 0, NULL);
clk[clk_HFPERCLKVCMP] = clk_register_gate(NULL, "HFPERCLK.VCMP",
"HFXO", 0, base + CMU_HFPERCLKEN0, 14, 0, NULL);
clk[clk_HFPERCLKPRS] = clk_register_gate(NULL, "HFPERCLK.PRS",
"HFXO", 0, base + CMU_HFPERCLKEN0, 15, 0, NULL);
clk[clk_HFPERCLKADC0] = clk_register_gate(NULL, "HFPERCLK.ADC0",
"HFXO", 0, base + CMU_HFPERCLKEN0, 16, 0, NULL);
clk[clk_HFPERCLKDAC0] = clk_register_gate(NULL, "HFPERCLK.DAC0",
"HFXO", 0, base + CMU_HFPERCLKEN0, 17, 0, NULL);
of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
}
CLK_OF_DECLARE(efm32ggcmu, "efm32gg,cmu", efm32gg_cmu_init);
Computing file changes ...
