[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-Id: <20170125.144042.372817990268077333.davem@davemloft.net>
Date: Wed, 25 Jan 2017 14:40:42 -0500 (EST)
From: David Miller <davem@...emloft.net>
To: geert+renesas@...der.be
Cc: f.fainelli@...il.com, zach.brown@...com,
volodymyr.bendiuga@...il.com, andrew@...n.ch,
magnus.oberg@...termo.se, netdev@...r.kernel.org,
linux-renesas-soc@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 0/3] net: phy: leds: Fix truncated LED trigger names
and crashes
From: Geert Uytterhoeven <geert+renesas@...der.be>
Date: Wed, 25 Jan 2017 11:39:47 +0100
> I started seeing crashes during s2ram and poweroff on all my ARM boards,
> like:
>
> Unable to handle kernel NULL pointer dereference at virtual address 00000000
> ...
> [<c04116d4>] (__list_del_entry_valid) from [<c05e8948>] (led_trigger_unregister+0x34/0xcc)
> [<c05e8948>] (led_trigger_unregister) from [<c05336c4>] (phy_led_triggers_unregister+0x28/0x34)
> [<c05336c4>] (phy_led_triggers_unregister) from [<c0531d44>] (phy_detach+0x30/0x74)
> [<c0531d44>] (phy_detach) from [<c0538bdc>] (sh_eth_close+0x64/0x9c)
> [<c0538bdc>] (sh_eth_close) from [<c04d4ce0>] (dpm_run_callback+0x48/0xc8)
>
> or:
>
> list_del corruption. prev->next should be dede6540, but was 2e323931
> ------------[ cut here ]------------
> kernel BUG at lib/list_debug.c:52!
> ...
> [<c02f6d70>] (__list_del_entry_valid) from [<c0425168>] (led_trigger_unregister+0x34/0xcc)
> [<c0425168>] (led_trigger_unregister) from [<c03a05a0>] (phy_led_triggers_unregister+0x28/0x34)
> [<c03a05a0>] (phy_led_triggers_unregister) from [<c039ec04>] (phy_detach+0x30/0x74)
> [<c039ec04>] (phy_detach) from [<c03a4fc0>] (sh_eth_close+0x6c/0xa4)
> [<c03a4fc0>] (sh_eth_close) from [<c0483234>] (__dev_close_many+0xac/0xd0)
>
> As the only clue was a kernel message like
>
> sh-eth ee700000.ethernet eth0: No phy led trigger registered for speed(100)
>
> I had to bisected this, leading to commit 4567d686f5c6d955 ("phy:
> increase size of MII_BUS_ID_SIZE and bus_id"). Reverting that commit
> fixed the issue.
>
> More investigation revealed the crashes are due to the combination of
> two things:
> - Truncated LED trigger names, leading to duplicate names, and
> registration failures,
> - Bad error handling in case of registration failures.
>
> Both are fixed by this patch series.
Thanks for tracking this down and fixing it.
Series applied, thanks.
Powered by blists - more mailing lists