From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, syzbot <syzkaller@googlegroups.com>,
Eric Dumazet <edumazet@google.com>,
Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH 4.14 54/65] tick/sched: Annotate lockless access to last_jiffies_update
Date: Wed, 22 Jan 2020 10:29:39 +0100 [thread overview]
Message-ID: <20200122092759.229907722@linuxfoundation.org> (raw)
In-Reply-To: <20200122092750.976732974@linuxfoundation.org>
From: Eric Dumazet <edumazet@google.com>
commit de95a991bb72e009f47e0c4bbc90fc5f594588d5 upstream.
syzbot (KCSAN) reported a data-race in tick_do_update_jiffies64():
BUG: KCSAN: data-race in tick_do_update_jiffies64 / tick_do_update_jiffies64
write to 0xffffffff8603d008 of 8 bytes by interrupt on cpu 1:
tick_do_update_jiffies64+0x100/0x250 kernel/time/tick-sched.c:73
tick_sched_do_timer+0xd4/0xe0 kernel/time/tick-sched.c:138
tick_sched_timer+0x43/0xe0 kernel/time/tick-sched.c:1292
__run_hrtimer kernel/time/hrtimer.c:1514 [inline]
__hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1576
hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
arch_local_irq_restore arch/x86/include/asm/paravirt.h:756 [inline]
kcsan_setup_watchpoint+0x1d4/0x460 kernel/kcsan/core.c:436
check_access kernel/kcsan/core.c:466 [inline]
__tsan_read1 kernel/kcsan/core.c:593 [inline]
__tsan_read1+0xc2/0x100 kernel/kcsan/core.c:593
kallsyms_expand_symbol.constprop.0+0x70/0x160 kernel/kallsyms.c:79
kallsyms_lookup_name+0x7f/0x120 kernel/kallsyms.c:170
insert_report_filterlist kernel/kcsan/debugfs.c:155 [inline]
debugfs_write+0x14b/0x2d0 kernel/kcsan/debugfs.c:256
full_proxy_write+0xbd/0x100 fs/debugfs/file.c:225
__vfs_write+0x67/0xc0 fs/read_write.c:494
vfs_write fs/read_write.c:558 [inline]
vfs_write+0x18a/0x390 fs/read_write.c:542
ksys_write+0xd5/0x1b0 fs/read_write.c:611
__do_sys_write fs/read_write.c:623 [inline]
__se_sys_write fs/read_write.c:620 [inline]
__x64_sys_write+0x4c/0x60 fs/read_write.c:620
do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x44/0xa9
read to 0xffffffff8603d008 of 8 bytes by task 0 on cpu 0:
tick_do_update_jiffies64+0x2b/0x250 kernel/time/tick-sched.c:62
tick_nohz_update_jiffies kernel/time/tick-sched.c:505 [inline]
tick_nohz_irq_enter kernel/time/tick-sched.c:1257 [inline]
tick_irq_enter+0x139/0x1c0 kernel/time/tick-sched.c:1274
irq_enter+0x4f/0x60 kernel/softirq.c:354
entering_irq arch/x86/include/asm/apic.h:517 [inline]
entering_ack_irq arch/x86/include/asm/apic.h:523 [inline]
smp_apic_timer_interrupt+0x55/0x280 arch/x86/kernel/apic/apic.c:1133
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571
default_idle_call+0x1e/0x40 kernel/sched/idle.c:94
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x1af/0x280 kernel/sched/idle.c:263
cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355
rest_init+0xec/0xf6 init/main.c:452
arch_call_rest_init+0x17/0x37
start_kernel+0x838/0x85e init/main.c:786
x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490
x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:471
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Use READ_ONCE() and WRITE_ONCE() to annotate this expected race.
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191205045619.204946-1-edumazet@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/time/tick-sched.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -60,8 +60,9 @@ static void tick_do_update_jiffies64(kti
/*
* Do a quick check without holding jiffies_lock:
+ * The READ_ONCE() pairs with two updates done later in this function.
*/
- delta = ktime_sub(now, last_jiffies_update);
+ delta = ktime_sub(now, READ_ONCE(last_jiffies_update));
if (delta < tick_period)
return;
@@ -72,8 +73,9 @@ static void tick_do_update_jiffies64(kti
if (delta >= tick_period) {
delta = ktime_sub(delta, tick_period);
- last_jiffies_update = ktime_add(last_jiffies_update,
- tick_period);
+ /* Pairs with the lockless read in this function. */
+ WRITE_ONCE(last_jiffies_update,
+ ktime_add(last_jiffies_update, tick_period));
/* Slow path for long timeouts */
if (unlikely(delta >= tick_period)) {
@@ -81,8 +83,10 @@ static void tick_do_update_jiffies64(kti
ticks = ktime_divns(delta, incr);
- last_jiffies_update = ktime_add_ns(last_jiffies_update,
- incr * ticks);
+ /* Pairs with the lockless read in this function. */
+ WRITE_ONCE(last_jiffies_update,
+ ktime_add_ns(last_jiffies_update,
+ incr * ticks));
}
do_timer(++ticks);
next prev parent reply other threads:[~2020-01-22 9:39 UTC|newest]
Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-22 9:28 [PATCH 4.14 00/65] 4.14.167-stable review Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 01/65] dt-bindings: reset: meson8b: fix duplicate reset IDs Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 02/65] clk: Dont try to enable critical clocks if prepare failed Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 03/65] ASoC: msm8916-wcd-analog: Fix selected events for MIC BIAS External1 Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 04/65] ALSA: seq: Fix racy access for queue timer in proc read Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 05/65] Fix built-in early-load Intel microcode alignment Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 06/65] block: fix an integer overflow in logical block size Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 07/65] ARM: dts: am571x-idk: Fix gpios property to have the correct gpio number Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 08/65] iio: buffer: align the size of scan bytes to size of the largest element Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 09/65] USB: serial: simple: Add Motorola Solutions TETRA MTP3xxx and MTP85xx Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 10/65] USB: serial: option: Add support for Quectel RM500Q Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 11/65] USB: serial: opticon: fix control-message timeouts Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 12/65] USB: serial: option: add support for Quectel RM500Q in QDL mode Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 13/65] USB: serial: suppress driver bind attributes Greg Kroah-Hartman
2020-01-22 9:28 ` [PATCH 4.14 14/65] USB: serial: ch341: handle unbound port at reset_resume Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 15/65] USB: serial: io_edgeport: add missing active-port sanity check Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 16/65] USB: serial: keyspan: handle unbound ports Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 17/65] USB: serial: quatech2: " Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 18/65] scsi: fnic: fix invalid stack access Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 19/65] scsi: mptfusion: Fix double fetch bug in ioctl Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 20/65] ptrace: reintroduce usage of subjective credentials in ptrace_has_cap() Greg Kroah-Hartman
2020-01-23 23:01 ` Guenter Roeck
2020-01-24 7:38 ` Greg Kroah-Hartman
2020-04-20 14:15 ` Ben Hutchings
2020-01-22 9:29 ` [PATCH 4.14 21/65] usb: core: hub: Improved device recognition on remote wakeup Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 22/65] x86/resctrl: Fix an imbalance in domain_remove_cpu() Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 23/65] x86/efistub: Disable paging at mixed mode entry Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 24/65] perf hists: Fix variable names inconsistency in hists__for_each() macro Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 25/65] perf report: Fix incorrectly added dimensions as switch perf data file Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 26/65] mm/shmem.c: thp, shmem: fix conflict of above-47bit hint address and PMD alignment Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 27/65] btrfs: fix memory leak in qgroup accounting Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 28/65] mm/page-writeback.c: avoid potential division by zero in wb_min_max_ratio() Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 29/65] net: stmmac: 16KB buffer must be 16 byte aligned Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 30/65] net: stmmac: Enable 16KB buffer size Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 31/65] USB: serial: io_edgeport: use irqsave() in USBs complete callback Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 32/65] USB: serial: io_edgeport: handle unbound ports on URB completion Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 33/65] mm/huge_memory.c: make __thp_get_unmapped_area static Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 34/65] mm/huge_memory.c: thp: fix conflict of above-47bit hint address and PMD alignment Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 35/65] arm64: dts: agilex/stratix10: fix pmu interrupt numbers Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 36/65] cfg80211: fix page refcount issue in A-MSDU decap Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 37/65] netfilter: fix a use-after-free in mtype_destroy() Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 38/65] netfilter: arp_tables: init netns pointer in xt_tgdtor_param struct Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 39/65] NFC: pn533: fix bulk-message timeout Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 40/65] batman-adv: Fix DAT candidate selection on little endian systems Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 41/65] macvlan: use skb_reset_mac_header() in macvlan_queue_xmit() Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 42/65] hv_netvsc: Fix memory leak when removing rndis device Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 43/65] net: dsa: tag_qca: fix doubled Tx statistics Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 44/65] net: hns: fix soft lockup when there is not enough memory Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 45/65] net: usb: lan78xx: limit size of local TSO packets Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 46/65] net/wan/fsl_ucc_hdlc: fix out of bounds write on array utdm_info Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 47/65] ptp: free ptp device pin descriptors properly Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 48/65] r8152: add missing endpoint sanity check Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 49/65] tcp: fix marked lost packets not being retransmitted Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 50/65] xen/blkfront: Adjust indentation in xlvbd_alloc_gendisk Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 51/65] cw1200: Fix a signedness bug in cw1200_load_firmware() Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 52/65] arm64: dts: meson-gxl-s905x-khadas-vim: fix gpio-keys-polled node Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 53/65] cfg80211: check for set_wiphy_params Greg Kroah-Hartman
2020-01-22 9:29 ` Greg Kroah-Hartman [this message]
2020-01-22 9:29 ` [PATCH 4.14 55/65] Revert "arm64: dts: juno: add dma-ranges property" Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 56/65] reiserfs: fix handling of -EOPNOTSUPP in reiserfs_for_each_xattr Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 57/65] scsi: esas2r: unlock on error in esas2r_nvram_read_direct() Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 58/65] scsi: qla4xxx: fix double free bug Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 59/65] scsi: bnx2i: fix potential use after free Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 60/65] scsi: target: core: Fix a pr_debug() argument Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 61/65] scsi: qla2xxx: Fix qla2x00_request_irqs() for MSI Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 62/65] scsi: qla2xxx: fix rports not being mark as lost in sync fabric scan Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 63/65] scsi: core: scsi_trace: Use get_unaligned_be*() Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 64/65] perf probe: Fix wrong address verification Greg Kroah-Hartman
2020-01-22 9:29 ` [PATCH 4.14 65/65] regulator: ab8500: Remove SYSCLKREQ from enum ab8505_regulator_id Greg Kroah-Hartman
2020-01-22 14:39 ` [PATCH 4.14 00/65] 4.14.167-stable review Naresh Kamboju
[not found] ` <20200122092750.976732974-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>
2020-01-22 14:58 ` Jon Hunter
2020-01-22 14:58 ` Jon Hunter
2020-01-22 19:00 ` Guenter Roeck
2020-01-22 20:53 ` shuah
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