Re: [PATCH 5.10 000/589] 5.10.258-rc1 review

[Claudiu Beznea]

Hi, all,

On 6/1/26 11:47, Pavel Machek wrote:
> Hi!
>
> > This is the start of the stable review cycle for the 5.10.258 release.
> > There are 589 patches in this series, all will be posted as a response
> > to this one.  If anyone has any issues with these being applied, please
> > let me know.
>
> We see boot failures on 5.10-cip:
>
> https://gitlab.com/cip-project/cip-testing/linux-stable-rc-ci/-/pipelines/2564188475
> https://lava.ciplatform.org/scheduler/job/1451830

This should be related to the patch:

commit 0f86a559900f
Author: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
Date:   Tue Apr 7 14:37:41 2026 +0300

    phy: renesas: rcar-gen3-usb2: Lock around hardware registers and driver data

    commit 55a387ebb9219cbe4edfa8ba9996ccb0e7ad4932 upstream.

    The phy-rcar-gen3-usb2 driver exposes four individual PHYs that are
    requested and configured by PHY users. The struct phy_ops APIs access the
    same set of registers to configure all PHYs. Additionally, PHY settings can
    be modified through sysfs or an IRQ handler. While some struct phy_ops APIs
    are protected by a driver-wide mutex, others rely on individual
    PHY-specific mutexes.

    This approach can lead to various issues, including:
    1/ the IRQ handler may interrupt PHY settings in progress, racing with
       hardware configuration protected by a mutex lock
    2/ due to msleep(20) in rcar_gen3_init_otg(), while a configuration thread
       suspends to wait for the delay, another thread may try to configure
       another PHY (with phy_init() + phy_power_on()); re-running the
       phy_init() goes to the exact same configuration code, re-running the
       same hardware configuration on the same set of registers (and bits)
       which might impact the result of the msleep for the 1st configuring
       thread
    3/ sysfs can configure the hardware (though role_store()) and it can
       still race with the phy_init()/phy_power_on() APIs calling into the
       drivers struct phy_ops

    To address these issues, add a spinlock to protect hardware register access
    and driver private data structures (e.g., calls to
    rcar_gen3_is_any_rphy_initialized()). Checking driver-specific data remains
    necessary as all PHY instances share common settings. With this change,
    the existing mutex protection is removed and the cleanup.h helpers are
    used.

    While at it, to keep the code simpler, do not skip
    regulator_enable()/regulator_disable() APIs in
    rcar_gen3_phy_usb2_power_on()/rcar_gen3_phy_usb2_power_off() as the
    regulators enable/disable operations are reference counted anyway.

    [claudiu.beznea:
     - in rcar_gen3_init_otg(): fixed conflict by droppping ch->soc_no_adp_ctrl 
check
     - in rcar_gen3_phy_usb2_irq() use spin_lock()/spin_unlock() as scoped_guard()
       is not avaialable in v5.10
     - in probe(): replace mutex_init() with spin_lock_init()
     - rcar_gen3_phy_usb2_power_off() replaced scoped_guard() as it is not
       available in v5.10
     - in rcar_gen3_phy_usb2_power_on() droppped guard to avoid compilation
       warning "ISO C90 forbids mixed declarations and code"]

    Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
    Cc: stable@xxxxxxxxxxxxxxx
    Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
    Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
    Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
    Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
    Link: 
https://lore.kernel.org/r/20250507125032.565017-4-claudiu.beznea.uj@xxxxxxxxxxxxxx
    Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
    Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

In this backported version I failed to replaced the msleep() with mdelay() as it 
was in the original patch.

The following patch should fix this problem and align the v5.10 backport support 
with the currently upstream one: 
https://lore.kernel.org/all/20260501225859.504868-1-nobuhiro.iwamatsu.x90@mail.toshiba

Greg, since this fix ^ aligns v5.10 stable with the current upstream support, 
would there be a way to integrated it in v5.10 stable as well?

I am currently working to remove this long sleep in atomic context from upstream:
https://lore.kernel.org/all/20260528070826.478813-1-claudiu.beznea@xxxxxxxxxx

> This may be related to
>
> [PATCH v3] phy: renesas: rcar-gen3-usb2: Avoid long delay in atomic context

This is not yet integrated in upstream.

Thank you,
Claudiu

> but I don't see related patches in the shortlog below. I put Renesas
> people in the cc list, they should know more.
>
> Best regards,
> 									Pavel