From: Tao Liu <thomas.liu@ucloud.cn>
To: linux-rdma@vger.kernel.org
Cc: saeedm@nvidia.com, talgi@nvidia.com, leonro@nvidia.com,
mgurtovoy@nvidia.com, jgg@nvidia.com, yaminf@nvidia.com,
thomas.liu@ucloud.cn
Subject: [PATCH v3] linux/dim: Fix divide 0 in RDMA DIM.
Date: Mon, 27 Jun 2022 22:00:04 +0800 [thread overview]
Message-ID: <20220627140004.3099-1-thomas.liu@ucloud.cn> (raw)
Fix a divide 0 error in rdma_dim_stats_compare() when prev->cpe_ratio == 0.
CallTrace:
Hardware name: H3C R4900 G3/RS33M2C9S, BIOS 2.00.37P21 03/12/2020
task: ffff880194b78000 task.stack: ffffc90006714000
RIP: 0010:backport_rdma_dim+0x10e/0x240 [mlx_compat]
RSP: 0018:ffff880c10e83ec0 EFLAGS: 00010202
RAX: 0000000000002710 RBX: ffff88096cd7f780 RCX: 0000000000000064
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 000000001d7c6c09
R13: ffff88096cd7f780 R14: ffff880b174fe800 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff880c10e80000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000a0965b00 CR3: 000000000200a003 CR4: 00000000007606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<IRQ>
ib_poll_handler+0x43/0x80 [ib_core]
irq_poll_softirq+0xae/0x110
__do_softirq+0xd1/0x28c
irq_exit+0xde/0xf0
do_IRQ+0x54/0xe0
common_interrupt+0x8f/0x8f
</IRQ>
? cpuidle_enter_state+0xd9/0x2a0
? cpuidle_enter_state+0xc7/0x2a0
? do_idle+0x170/0x1d0
? cpu_startup_entry+0x6f/0x80
? start_secondary+0x1b9/0x210
? secondary_startup_64+0xa5/0xb0
Code: 0f 87 e1 00 00 00 8b 4c 24 14 44 8b 43 14 89 c8 4d 63 c8 44 29 c0 99 31 d0 29 d0 31 d2 48 98 48 8d 04 80 48 8d 04 80 48 c1 e0 02 <49> f7 f1 48 83 f8 0a 0f 86 c1 00 00 00 44 39 c1 7f 10 48 89 df
RIP: backport_rdma_dim+0x10e/0x240 [mlx_compat] RSP: ffff880c10e83ec0
Fixes: f4915455dcf0 ("linux/dim: Implement RDMA adaptive moderation (DIM)")
Signed-off-by: Tao Liu <thomas.liu@ucloud.cn>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Acked-by: Leon Romanovsky <leonro@nvidia.com>
---
include/linux/dim.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/dim.h b/include/linux/dim.h
index b698266d0035..6c5733981563 100644
--- a/include/linux/dim.h
+++ b/include/linux/dim.h
@@ -21,7 +21,7 @@
* We consider 10% difference as significant.
*/
#define IS_SIGNIFICANT_DIFF(val, ref) \
- (((100UL * abs((val) - (ref))) / (ref)) > 10)
+ ((ref) && (((100UL * abs((val) - (ref))) / (ref)) > 10))
/*
* Calculate the gap between two values.
--
2.30.1 (Apple Git-130)
next reply other threads:[~2022-06-27 14:01 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-27 14:00 Tao Liu [this message]
2022-06-28 7:10 ` [PATCH v3] linux/dim: Fix divide 0 in RDMA DIM Leon Romanovsky
2022-06-28 19:16 ` Jason Gunthorpe
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