[PATCH] x86/quirks: disable HPET on Intel Coffee Lake Refresh platforms

[PATCH] x86/quirks: disable HPET on Intel Coffee Lake Refresh platforms

[Jason A. Donenfeld]

This is a follow up of fc5db58539b4 ("x86/quirks: Disable HPET on Intel
Coffe Lake platforms"), which addressed the issue for 8th generation
Coffee Lake. Intel has released Coffee Lake again for 9th generation,
apparently still with the same bug:

clocksource: timekeeping watchdog on CPU3: Marking clocksource 'tsc' as unstable because the skew is too large:
clocksource:                       'hpet' wd_now: 24f422b8 wd_last: 247dea41 mask: ffffffff
clocksource:                       'tsc' cs_now: 144d927c4e cs_last: 140ba6e2a0 mask: ffffffffffffffff
tsc: Marking TSC unstable due to clocksource watchdog
TSC found unstable after boot, most likely due to broken BIOS. Use 'tsc=unstable'.
sched_clock: Marking unstable (26553416234, 4203921)<-(26567277071, -9656937)
clocksource: Switched to clocksource hpet

So, we add another quirk for the chipset

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
---
 arch/x86/kernel/early-quirks.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c
index 4cba91ec8049..a73f88dd7f86 100644
--- a/arch/x86/kernel/early-quirks.c
+++ b/arch/x86/kernel/early-quirks.c
@@ -712,6 +712,8 @@ static struct chipset early_qrk[] __initdata = {
 		PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet},
 	{ PCI_VENDOR_ID_INTEL, 0x3ec4,
 		PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet},
+	{ PCI_VENDOR_ID_INTEL, 0x3e20,
+		PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet},
 	{ PCI_VENDOR_ID_BROADCOM, 0x4331,
 	  PCI_CLASS_NETWORK_OTHER, PCI_ANY_ID, 0, apple_airport_reset},
 	{}
-- 
2.24.0

Re: [PATCH] x86/quirks: disable HPET on Intel Coffee Lake Refresh platforms

[Jason A. Donenfeld]

Hey Thomas,

Can we perhaps get this into 5.5-rc2?

It'd be nice if Intel could give us a list of SKUs that are affected
(as you asked in another email thread), but barring that, the best we
can do is whack-a-mole like this. I'm typing you this email on the
hardware that this patch addresses.

Jason

On Tue, Dec 3, 2019 at 9:57 PM Jason A. Donenfeld <Jason@zx2c4.com> wrote:
>
> This is a follow up of fc5db58539b4 ("x86/quirks: Disable HPET on Intel
> Coffe Lake platforms"), which addressed the issue for 8th generation
> Coffee Lake. Intel has released Coffee Lake again for 9th generation,
> apparently still with the same bug:
>
> clocksource: timekeeping watchdog on CPU3: Marking clocksource 'tsc' as unstable because the skew is too large:
> clocksource:                       'hpet' wd_now: 24f422b8 wd_last: 247dea41 mask: ffffffff
> clocksource:                       'tsc' cs_now: 144d927c4e cs_last: 140ba6e2a0 mask: ffffffffffffffff
> tsc: Marking TSC unstable due to clocksource watchdog
> TSC found unstable after boot, most likely due to broken BIOS. Use 'tsc=unstable'.
> sched_clock: Marking unstable (26553416234, 4203921)<-(26567277071, -9656937)
> clocksource: Switched to clocksource hpet
>
> So, we add another quirk for the chipset
>
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> Cc: Feng Tang <feng.tang@intel.com>
> Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: stable@vger.kernel.org
> ---
>  arch/x86/kernel/early-quirks.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c
> index 4cba91ec8049..a73f88dd7f86 100644
> --- a/arch/x86/kernel/early-quirks.c
> +++ b/arch/x86/kernel/early-quirks.c
> @@ -712,6 +712,8 @@ static struct chipset early_qrk[] __initdata = {
>                 PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet},
>         { PCI_VENDOR_ID_INTEL, 0x3ec4,
>                 PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet},
> +       { PCI_VENDOR_ID_INTEL, 0x3e20,
> +               PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet},
>         { PCI_VENDOR_ID_BROADCOM, 0x4331,
>           PCI_CLASS_NETWORK_OTHER, PCI_ANY_ID, 0, apple_airport_reset},
>         {}
> --
> 2.24.0

Re: [PATCH] x86/quirks: disable HPET on Intel Coffee Lake Refresh platforms

[Jason A. Donenfeld]

Hi Sasha,

On Wed, Dec 11, 2019 at 6:36 PM Sasha Levin <sashal@kernel.org> wrote:
>
> Hi,
>
> [This is an automated email]
>
> This commit has been processed because it contains a -stable tag.
> The stable tag indicates that it's relevant for the following trees: all
>
> The bot has tested the following trees: v5.4.2, v5.3.15, v4.19.88, v4.14.158, v4.9.206, v4.4.206.
>
> v5.4.2: Build OK!
> v5.3.15: Build OK!
> v4.19.88: Failed to apply! Possible dependencies:
>     fc5db58539b4 ("x86/quirks: Disable HPET on Intel Coffe Lake platforms")
>
> v4.14.158: Failed to apply! Possible dependencies:
>     fc5db58539b4 ("x86/quirks: Disable HPET on Intel Coffe Lake platforms")
>
> v4.9.206: Failed to apply! Possible dependencies:
>     fc5db58539b4 ("x86/quirks: Disable HPET on Intel Coffe Lake platforms")
>
> v4.4.206: Failed to apply! Possible dependencies:
>     fc5db58539b4 ("x86/quirks: Disable HPET on Intel Coffe Lake platforms")
>
>
> NOTE: The patch will not be queued to stable trees until it is upstream.
>
> How should we proceed with this patch?

It probably makes sense to backport the dependency commit mentioned.

Jason