linux-kernel - Re: [PATCH] platform/x86/amd/pmc: Only disable IRQ1 wakeup where i8042 actually enabled it

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]

Message-ID: <a5781d0a-0a58-a708-1f8f-f9ade14ade52@linux.intel.com>
Date: Sun, 29 Dec 2024 18:58:46 +0200 (EET)
From: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>
To: "Maciej S. Szmigiero" <mail@...iej.szmigiero.name>
cc: Shyam Sundar S K <Shyam-sundar.S-k@....com>, 
    Mario Limonciello <mario.limonciello@....com>, 
    Hans de Goede <hdegoede@...hat.com>, platform-driver-x86@...r.kernel.org, 
    LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] platform/x86/amd/pmc: Only disable IRQ1 wakeup where
 i8042 actually enabled it

On Sun, 29 Dec 2024, Maciej S. Szmigiero wrote:

> Wakeup for IRQ1 should be disabled only in cases where i8042 had actually
> enabled it, otherwise "wake_depth" for this IRQ will try do drop below zero
> and there will be an unpleasant WARN() logged:
> kernel: atkbd serio0: Disabling IRQ1 wakeup source to avoid platform firmware bug
> kernel: ------------[ cut here ]------------
> kernel: Unbalanced IRQ 1 wake disable
> kernel: WARNING: CPU: 10 PID: 6431 at kernel/irq/manage.c:920 irq_set_irq_wake+0x147/0x1a0
> 
> To fix this call the PMC suspend handler only from the same set of
> dev_pm_ops handlers as i8042_pm_suspend() is called, which currently means
> just the ".suspend" handler.
> Previously, the code would use DEFINE_SIMPLE_DEV_PM_OPS() to define its
> dev_pm_ops, which also called this handler on ".freeze" and ".poweroff".
> 
> To reproduce this issue try hibernating (S4) the machine after a fresh boot
> without putting it into s2idle first.
> 
> Fixes: 8e60615e8932 ("platform/x86/amd: pmc: Disable IRQ1 wakeup for RN/CZN")
> Signed-off-by: Maciej S. Szmigiero <mail@...iej.szmigiero.name>
> ---
>  drivers/platform/x86/amd/pmc/pmc.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
> index 26b878ee5191..a254debb9256 100644
> --- a/drivers/platform/x86/amd/pmc/pmc.c
> +++ b/drivers/platform/x86/amd/pmc/pmc.c
> @@ -947,6 +947,10 @@ static int amd_pmc_suspend_handler(struct device *dev)
>  {
>  	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
>  
> +	/*
> +	 * Must be called only from the same set of dev_pm_ops handlers
> +	 * as i8042_pm_suspend() is called: currently just from .suspend.
> +	 */
>  	if (pdev->disable_8042_wakeup && !disable_workarounds) {
>  		int rc = amd_pmc_wa_irq1(pdev);
>  
> @@ -959,7 +963,9 @@ static int amd_pmc_suspend_handler(struct device *dev)
>  	return 0;
>  }
>  
> -static DEFINE_SIMPLE_DEV_PM_OPS(amd_pmc_pm, amd_pmc_suspend_handler, NULL);
> +static const struct dev_pm_ops amd_pmc_pm = {
> +	.suspend = amd_pmc_suspend_handler,
> +};

???

I cannot see what this change is supposed to achieve. 

#define _DEFINE_DEV_PM_OPS(name, \
                           suspend_fn, resume_fn, \
                           runtime_suspend_fn, runtime_resume_fn, idle_fn) \
const struct dev_pm_ops name = { \
        SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
        RUNTIME_PM_OPS(runtime_suspend_fn, runtime_resume_fn, idle_fn) \
}

#define DEFINE_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
        _DEFINE_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL)

#define SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
        .suspend = pm_sleep_ptr(suspend_fn), \
        .resume = pm_sleep_ptr(resume_fn), \
        .freeze = pm_sleep_ptr(suspend_fn), \
        .thaw = pm_sleep_ptr(resume_fn), \
        .poweroff = pm_sleep_ptr(suspend_fn), \
        .restore = pm_sleep_ptr(resume_fn),

#define pm_sleep_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM_SLEEP), (_ptr))

Under what circumstances does this change result in some difference?

-- 
 i.