* [PATCH] drivers: net: cpsw: fix kmemleak false-positive reports for sk buffers
@ 2016-08-09 12:09 Grygorii Strashko
2016-08-09 15:19 ` Catalin Marinas
2016-08-10 16:55 ` Mugunthan V N
0 siblings, 2 replies; 3+ messages in thread
From: Grygorii Strashko @ 2016-08-09 12:09 UTC (permalink / raw)
To: David S. Miller, netdev, Mugunthan V N, Catalin Marinas
Cc: Sekhar Nori, linux-kernel, linux-omap, Grygorii Strashko
Kmemleak reports following false positive memory leaks for each sk
buffers allocated by CPSW (__netdev_alloc_skb_ip_align()) in
cpsw_ndo_open() and cpsw_rx_handler():
unreferenced object 0xea915000 (size 2048):
comm "systemd-network", pid 713, jiffies 4294938323 (age 102.180s)
hex dump (first 32 bytes):
00 58 91 ea ff ff ff ff ff ff ff ff ff ff ff ff .X..............
ff ff ff ff ff ff fd 0f 00 00 00 00 00 00 00 00 ................
backtrace:
[<c0108680>] __kmalloc_track_caller+0x1a4/0x230
[<c0529eb4>] __alloc_skb+0x68/0x16c
[<c052c884>] __netdev_alloc_skb+0x40/0x104
[<bf1ad29c>] cpsw_ndo_open+0x374/0x670 [ti_cpsw]
[<c053c3d4>] __dev_open+0xb0/0x114
[<c053c690>] __dev_change_flags+0x9c/0x14c
[<c053c760>] dev_change_flags+0x20/0x50
[<c054bdcc>] do_setlink+0x2cc/0x78c
[<c054c358>] rtnl_setlink+0xcc/0x100
[<c054b34c>] rtnetlink_rcv_msg+0x184/0x224
[<c056467c>] netlink_rcv_skb+0xa8/0xc4
[<c054b1c0>] rtnetlink_rcv+0x2c/0x34
[<c0564018>] netlink_unicast+0x16c/0x1f8
[<c0564498>] netlink_sendmsg+0x334/0x348
[<c052015c>] sock_sendmsg+0x1c/0x2c
[<c05213e0>] SyS_sendto+0xc0/0xe8
unreferenced object 0xec861780 (size 192):
comm "softirq", pid 0, jiffies 4294938759 (age 109.540s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 b0 5a ed 00 00 00 00 00 00 00 00 ......Z.........
backtrace:
[<c0107830>] kmem_cache_alloc+0x190/0x208
[<c052c768>] __build_skb+0x30/0x98
[<c052c8fc>] __netdev_alloc_skb+0xb8/0x104
[<bf1abc54>] cpsw_rx_handler+0x68/0x1e4 [ti_cpsw]
[<bf11aa30>] __cpdma_chan_free+0xa8/0xc4 [davinci_cpdma]
[<bf11ab98>] __cpdma_chan_process+0x14c/0x16c [davinci_cpdma]
[<bf11abfc>] cpdma_chan_process+0x44/0x5c [davinci_cpdma]
[<bf1adc78>] cpsw_rx_poll+0x1c/0x9c [ti_cpsw]
[<c0539180>] net_rx_action+0x1f0/0x2ec
[<c003881c>] __do_softirq+0x134/0x258
[<c0038a00>] do_softirq+0x68/0x70
[<c0038adc>] __local_bh_enable_ip+0xd4/0xe8
[<c0640994>] _raw_spin_unlock_bh+0x30/0x34
[<c05f4e9c>] igmp6_group_added+0x4c/0x1bc
[<c05f6600>] ipv6_dev_mc_inc+0x398/0x434
[<c05dba74>] addrconf_dad_work+0x224/0x39c
This happens because CPSW allocates SK buffers and then passes
pointers on them in CPDMA where they stored in internal CPPI RAM
(SRAM) which belongs to DEV MMIO space. Kmemleak does not scan IO
memory and so reports memory leaks.
Hence, mark allocated sk buffers as false positive explicitly.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
drivers/net/ethernet/ti/cpsw.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 0805855..0456e0e 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -732,6 +732,7 @@ static void cpsw_rx_handler(void *token, int len, int status)
netif_receive_skb(skb);
ndev->stats.rx_bytes += len;
ndev->stats.rx_packets++;
+ kmemleak_not_leak(new_skb);
} else {
ndev->stats.rx_dropped++;
new_skb = skb;
@@ -1323,6 +1324,7 @@ static int cpsw_ndo_open(struct net_device *ndev)
kfree_skb(skb);
goto err_cleanup;
}
+ kmemleak_not_leak(skb);
}
/* continue even if we didn't manage to submit all
* receive descs
--
2.9.2
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] drivers: net: cpsw: fix kmemleak false-positive reports for sk buffers
2016-08-09 12:09 [PATCH] drivers: net: cpsw: fix kmemleak false-positive reports for sk buffers Grygorii Strashko
@ 2016-08-09 15:19 ` Catalin Marinas
2016-08-10 16:55 ` Mugunthan V N
1 sibling, 0 replies; 3+ messages in thread
From: Catalin Marinas @ 2016-08-09 15:19 UTC (permalink / raw)
To: Grygorii Strashko
Cc: David S. Miller, netdev, Mugunthan V N, Sekhar Nori, linux-kernel,
linux-omap
On Tue, Aug 09, 2016 at 03:09:44PM +0300, Grygorii Strashko wrote:
> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
> index 0805855..0456e0e 100644
> --- a/drivers/net/ethernet/ti/cpsw.c
> +++ b/drivers/net/ethernet/ti/cpsw.c
> @@ -732,6 +732,7 @@ static void cpsw_rx_handler(void *token, int len, int status)
> netif_receive_skb(skb);
> ndev->stats.rx_bytes += len;
> ndev->stats.rx_packets++;
> + kmemleak_not_leak(new_skb);
> } else {
> ndev->stats.rx_dropped++;
> new_skb = skb;
> @@ -1323,6 +1324,7 @@ static int cpsw_ndo_open(struct net_device *ndev)
> kfree_skb(skb);
> goto err_cleanup;
> }
> + kmemleak_not_leak(skb);
Nitpick: I would add a short comment above the kmemleak_not_leak() calls
on why there is a false positive. Otherwise:
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] drivers: net: cpsw: fix kmemleak false-positive reports for sk buffers
2016-08-09 12:09 [PATCH] drivers: net: cpsw: fix kmemleak false-positive reports for sk buffers Grygorii Strashko
2016-08-09 15:19 ` Catalin Marinas
@ 2016-08-10 16:55 ` Mugunthan V N
1 sibling, 0 replies; 3+ messages in thread
From: Mugunthan V N @ 2016-08-10 16:55 UTC (permalink / raw)
To: Grygorii Strashko, David S. Miller, netdev, Catalin Marinas
Cc: Sekhar Nori, linux-kernel, linux-omap
On Tuesday 09 August 2016 05:39 PM, Grygorii Strashko wrote:
> Kmemleak reports following false positive memory leaks for each sk
> buffers allocated by CPSW (__netdev_alloc_skb_ip_align()) in
> cpsw_ndo_open() and cpsw_rx_handler():
>
> unreferenced object 0xea915000 (size 2048):
> comm "systemd-network", pid 713, jiffies 4294938323 (age 102.180s)
> hex dump (first 32 bytes):
> 00 58 91 ea ff ff ff ff ff ff ff ff ff ff ff ff .X..............
> ff ff ff ff ff ff fd 0f 00 00 00 00 00 00 00 00 ................
> backtrace:
> [<c0108680>] __kmalloc_track_caller+0x1a4/0x230
> [<c0529eb4>] __alloc_skb+0x68/0x16c
> [<c052c884>] __netdev_alloc_skb+0x40/0x104
> [<bf1ad29c>] cpsw_ndo_open+0x374/0x670 [ti_cpsw]
> [<c053c3d4>] __dev_open+0xb0/0x114
> [<c053c690>] __dev_change_flags+0x9c/0x14c
> [<c053c760>] dev_change_flags+0x20/0x50
> [<c054bdcc>] do_setlink+0x2cc/0x78c
> [<c054c358>] rtnl_setlink+0xcc/0x100
> [<c054b34c>] rtnetlink_rcv_msg+0x184/0x224
> [<c056467c>] netlink_rcv_skb+0xa8/0xc4
> [<c054b1c0>] rtnetlink_rcv+0x2c/0x34
> [<c0564018>] netlink_unicast+0x16c/0x1f8
> [<c0564498>] netlink_sendmsg+0x334/0x348
> [<c052015c>] sock_sendmsg+0x1c/0x2c
> [<c05213e0>] SyS_sendto+0xc0/0xe8
>
> unreferenced object 0xec861780 (size 192):
> comm "softirq", pid 0, jiffies 4294938759 (age 109.540s)
> hex dump (first 32 bytes):
> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
> 00 00 00 00 00 b0 5a ed 00 00 00 00 00 00 00 00 ......Z.........
> backtrace:
> [<c0107830>] kmem_cache_alloc+0x190/0x208
> [<c052c768>] __build_skb+0x30/0x98
> [<c052c8fc>] __netdev_alloc_skb+0xb8/0x104
> [<bf1abc54>] cpsw_rx_handler+0x68/0x1e4 [ti_cpsw]
> [<bf11aa30>] __cpdma_chan_free+0xa8/0xc4 [davinci_cpdma]
> [<bf11ab98>] __cpdma_chan_process+0x14c/0x16c [davinci_cpdma]
> [<bf11abfc>] cpdma_chan_process+0x44/0x5c [davinci_cpdma]
> [<bf1adc78>] cpsw_rx_poll+0x1c/0x9c [ti_cpsw]
> [<c0539180>] net_rx_action+0x1f0/0x2ec
> [<c003881c>] __do_softirq+0x134/0x258
> [<c0038a00>] do_softirq+0x68/0x70
> [<c0038adc>] __local_bh_enable_ip+0xd4/0xe8
> [<c0640994>] _raw_spin_unlock_bh+0x30/0x34
> [<c05f4e9c>] igmp6_group_added+0x4c/0x1bc
> [<c05f6600>] ipv6_dev_mc_inc+0x398/0x434
> [<c05dba74>] addrconf_dad_work+0x224/0x39c
>
> This happens because CPSW allocates SK buffers and then passes
> pointers on them in CPDMA where they stored in internal CPPI RAM
> (SRAM) which belongs to DEV MMIO space. Kmemleak does not scan IO
> memory and so reports memory leaks.
>
> Hence, mark allocated sk buffers as false positive explicitly.
>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Mugunthan V N <mugunthanvnm@ti.com>
Regards
Mugunthan V N
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2016-08-10 16:55 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-08-09 12:09 [PATCH] drivers: net: cpsw: fix kmemleak false-positive reports for sk buffers Grygorii Strashko
2016-08-09 15:19 ` Catalin Marinas
2016-08-10 16:55 ` Mugunthan V N
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).