Re: [PATCH] scsi: sd: Revert "Rework asynchronous resume support"

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Bart,

On Mon, Aug 22, 2022 at 4:52 AM Bart Van Assche <bvanassche@acm.org> wrote:
> On 8/21/22 02:16, Geert Uytterhoeven wrote:
> > It looks like there is a (different) regression in v6.1-rc1 related
> > to s2idle and s2ram, which is not fixed by this patch.  In fact it
> > also happens on boards where SATA is not used, it is just less likely
> > to happen on the non-SATA boards.
> > I still have to bisect it, which may take some time, as the issue is
> > not 100% reproducible.
>
> What kind of regression are you encountering? A crash, a hang or
> something else? Are any call traces available?

A lock-up (magic sysrq does not work) during s2idle.
I tried bisecting it yesterday, but failed.
On v6.0-rc1 (and rc2) it happens ca. 25% of the time, but the closer
I get to v5.19, the less likely it is to happen. Apparently 100
successful s2idle cycles was not enough to declare a kernel good...

    Freezing ...
    Filesystems sync: 0.001 seconds
    Freezing user space processes ... (elapsed 0.001 seconds) done.
    OOM killer disabled.
    Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
    sd 0:0:0:0: [sda] Synchronizing SCSI cache
    sd 0:0:0:0: [sda] Stopping disk

---> hangs here if it happens

    ravb e6800000.ethernet eth0: Link is Down
    sd 0:0:0:0: [sda] Starting disk
    Micrel KSZ9031 Gigabit PHY e6800000.ethernet-ffffffff:00: attached
PHY driver (mii_bus:phy_addr=e6800000.ethernet-ffffffff:00, irq=186)
    ata1: link resume succeeded after 1 retries
    ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
    ata1.00: configured for UDMA/133
    OOM killer enabled.
    Restarting tasks ... done.
    random: crng reseeded on system resumption
    PM: suspend exit
    ravb e6800000.ethernet eth0: Link is Up - 1Gbps/Full - flow control off

> I posted another revert earlier today but that revert is for code paths
> not related to suspend/resume functionality. See also
> https://lore.kernel.org/linux-scsi/20220821220502.13685-1-bvanassche@acm.org/

Unlikely to be the case, but I'll give it a try later...

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds