linux-kernel - Re: [PATCH] i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 13 Sep 2016 13:38:16 +0100
From:   Sudeep Holla <sudeep.holla@....com>
To:     open list <linux-kernel@...r.kernel.org>,
        linux-i2c@...r.kernel.org, linux-soc@...r.kernel.org,
        linux-arm-msm@...r.kernel.org
Cc:     Sudeep Holla <sudeep.holla@....com>,
        Andy Gross <andy.gross@...aro.org>,
        David Brown <david.brown@...aro.org>,
        Wolfram Sang <wsa@...-dreams.de>
Subject: Re: [PATCH] i2c: qup: skip qup_i2c_suspend if the device is already
 runtime suspended

On Thu, Aug 25, 2016 at 12:23 PM, Sudeep Holla <sudeep.holla@....com> wrote:
> If the i2c device is already runtime suspended, if qup_i2c_suspend is
> executed during suspend-to-idle or suspend-to-ram it will result in the
> following splat:
>
> WARNING: CPU: 3 PID: 1593 at drivers/clk/clk.c:476 clk_core_unprepare+0x80/0x90
> Modules linked in:
>
> CPU: 3 PID: 1593 Comm: bash Tainted: G        W       4.8.0-rc3 #14
> Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
> PC is at clk_core_unprepare+0x80/0x90
> LR is at clk_unprepare+0x28/0x40
> pc : [<ffff0000086eecf0>] lr : [<ffff0000086f0c58>] pstate: 60000145
> Call trace:
>  clk_core_unprepare+0x80/0x90
>  qup_i2c_disable_clocks+0x2c/0x68
>  qup_i2c_suspend+0x10/0x20
>  platform_pm_suspend+0x24/0x68
>  dpm_run_callback.isra.7+0x1c/0x70
>  __device_suspend+0xf4/0x298
>  dpm_suspend+0x10c/0x228
>  dpm_suspend_start+0x68/0x78
>  suspend_devices_and_enter+0xb8/0x460
>  pm_suspend+0x1ec/0x240
>  state_store+0x84/0xf8
>  kobj_attr_store+0x14/0x28
>  sysfs_kf_write+0x48/0x58
>  kernfs_fop_write+0x15c/0x1f8
>  __vfs_write+0x1c/0x100
>  vfs_write+0x9c/0x1b8
>  SyS_write+0x44/0xa0
>  el0_svc_naked+0x24/0x28
>
> This patch fixes the issue by executing qup_i2c_pm_suspend_runtime
> conditionally in qup_i2c_suspend.
>

Gentle ping !

Regards,
Sudeep