Re: [PATCH v2 0/5] tpm_tis: fix interrupts (again)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, 2020-10-15 at 11:48 -0700, Jerry Snitselaar wrote:
> James Bottomley @ 2020-10-15 08:36 MST:
> 
> > On Wed, 2020-10-14 at 13:58 -0700, Jerry Snitselaar wrote:
> > > Hans de Goede @ 2020-10-14 09:46 MST:
> > > 
> > > > Hi,
> > > > 
> > > > On 10/14/20 6:34 PM, Jerry Snitselaar wrote:
> > > > > Hans de Goede @ 2020-10-14 09:04 MST:
> > > > > 
> > > > > > Hi,
> > > > > > 
> > > > > > On 10/14/20 5:23 PM, James Bottomley wrote:
> > > > > > > On Wed, 2020-10-14 at 17:03 +0200, Hans de Goede wrote:
> > > > > > > > On 10/13/20 6:05 PM, Jerry Snitselaar wrote:
> > > > > > > > > James Bottomley @ 2020-10-13 08:24 MST:
> > > > > > > > > > On Tue, 2020-10-13 at 08:15 -0700, Jerry Snitselaar
> > > > > > > > > > wrote:
> > > > > > > > > > > Jarkko Sakkinen @ 2020-10-12 18:17 MST:
> > > > > > > [...]
> > > > > > > > > > > >     Jerry, once you have some bandwidth (no
> > > > > > > > > > > > rush,
> > > > > > > > > > > > does not land
> > > > > > > > > > > > before rc2), it would be great that if you
> > > > > > > > > > > > could
> > > > > > > > > > > > try this.
> > > > > > > > > > > > I'm emphasizing this just because of the
> > > > > > > > > > > > intersection. I
> > > > > > > > > > > > think it would also make senset to get tested-
> > > > > > > > > > > > by
> > > > > > > > > > > > from Nayna.
> > > > > > > > > > > 
> > > > > > > > > > > I will run some tests on some other systems I
> > > > > > > > > > > have
> > > > > > > > > > > access to.
> > > > > > > > > > > As noted in the other email I did a quick test
> > > > > > > > > > > with a
> > > > > > > > > > > t490s
> > > > > > > > > > > with an older bios that exhibits the problem
> > > > > > > > > > > originally
> > > > > > > > > > > reported when Stefan's patch enabled interrupts.
> > > > > > > > > > 
> > > > > > > > > > Well, it means there's still some other problem.  I
> > > > > > > > > > was
> > > > > > > > > > hoping
> > > > > > > > > > that because the rainbow pass system originally
> > > > > > > > > > exhibited the
> > > > > > > > > > same symptoms (interrupt storm) fixing it would
> > > > > > > > > > also
> > > > > > > > > > fix the t490
> > > > > > > > > > and the ineffective EOI bug looked like a great
> > > > > > > > > > candidate for
> > > > > > > > > > being the root cause.
> > > > > > > > > > 
> > > > > > > > > 
> > > > > > > > > Adding Hans to the list.
> > > > > > > > > 
> > > > > > > > > IIUC in the t490s case the problem lies with the
> > > > > > > > > hardware
> > > > > > > > > itself.
> > > > > > > > > Hans, is that correct?
> > > > > > > > 
> > > > > > > > More or less. AFAIK / have been told by Lenovo it is an
> > > > > > > > issue with
> > > > > > > > the configuration of the inerrupt-type of the GPIO pin
> > > > > > > > used
> > > > > > > > for the
> > > > > > > > IRQ, which is a firmware issue which could be fixed by
> > > > > > > > a
> > > > > > > > BIOS update
> > > > > > > > (the pin is setup as a direct-irq pin for the APIC, so
> > > > > > > > the
> > > > > > > > OS has no
> > > > > > > > control of the IRQ type since with APIC irqs this is
> > > > > > > > all
> > > > > > > > supposed to
> > > > > > > > be setup properly before hand).
> > > > > > > > 
> > > > > > > > But it is a model specific issue, if we denylist IRQ
> > > > > > > > usage
> > > > > > > > on this
> > > > > > > > Lenovo model (and probably a few others) then we should
> > > > > > > > be
> > > > > > > > able to
> > > > > > > > restore the IRQ code to normal functionality for all
> > > > > > > > other
> > > > > > > > device
> > > > > > > > models which declare an IRQ in their resource tables.
> > > > > > > I can do that with a quirk, but how do I identify the
> > > > > > > device?  TPM
> > > > > > > manufacturer and version? or do I have to use something
> > > > > > > like
> > > > > > > the ACPI
> > > > > > > bios version?
> > > > > > 
> > > > > > I'm not sure if the TPM ids are unique to one model/series
> > > > > > of
> > > > > > laptops.
> > > > > > 
> > > > > > So my idea for this was to match on DMI strings,
> > > > > > specifically
> > > > > > use a DMI match on the DMI_SYS_VENDOR and
> > > > > > DMI_PRODUCT_VERSION
> > > > > > strings (normally one would use DMI_PRODUCT_NAME but for
> > > > > > Lenovo
> > > > > > devices the string which you expect to be in
> > > > > > DMI_PRODUCT_NAME
> > > > > > is actually in DMI_PRODUCT_VERSION).
> > > > > > 
> > > > > > You can easily get the strings for your device by doing:
> > > > > > 
> > > > > > cat /sys/class/dmi/id/sys_vendor
> > > > > > cat /sys/class/dmi/id/product_version
> > > > > > 
> > > > > > Regards,
> > > > > > 
> > > > > > Hans
> > > > > Plus use dmi_get_date(DMI_BIOS_DATE,...) to check
> > > > > if the bios is older than the fixed bios? Has Lenovo
> > > > > released the fixed bios?
> > > > 
> > > > Maybe, the fixed BIOS-es which I have seen (for the X1C8,
> > > > broken BIOS was a pre-production BIOS) "fixed" this by
> > > > no longer listing an IRQ in the ACPI resources for the TPM.
> > > > 
> > > > Which means that the new BIOS still being on the deny list
> > > > does not matter since the IRQ support won't work anyways as
> > > > we no longer get an IRQ assigned.
> > > > 
> > > > So I don't think this is necessary and it will just complicate
> > > > things unnecessarily. This whole saga has already taken way
> > > > too long to fix. So IMHO the simplest fix where we just deny
> > > > list the broken models independent of BIOS versions and move
> > > > on seems best.
> > > > 
> > > > Regards,
> > > > 
> > > > Hans
> > > 
> > > This worked for me:
> > > 
> > > diff --git a/drivers/char/tpm/tpm_tis.c
> > > b/drivers/char/tpm/tpm_tis.c
> > > index 0b214963539d..abe674d1de6d 100644
> > > --- a/drivers/char/tpm/tpm_tis.c
> > > +++ b/drivers/char/tpm/tpm_tis.c
> > > @@ -27,6 +27,7 @@
> > >  #include <linux/of.h>
> > >  #include <linux/of_device.h>
> > >  #include <linux/kernel.h>
> > > +#include <linux/dmi.h>
> > >  #include "tpm.h"
> > >  #include "tpm_tis_core.h"
> > > 
> > > @@ -63,6 +64,26 @@ module_param(force, bool, 0444);
> > >  MODULE_PARM_DESC(force, "Force device probe rather than using
> > > ACPI
> > > entry");
> > >  #endif
> > > 
> > > +static int tpm_tis_disable_irq(const struct dmi_system_id *d)
> > > +{
> > > +       pr_notice("tpm_tis: %s detected: disabling
> > > interrupts.\n", d-
> > > > ident);
> > > +       interrupts = false;
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static const struct dmi_system_id tpm_tis_dmi_table[] = {
> > > +       {
> > > +               .callback = tpm_tis_disable_irq,
> > > +               .ident = "ThinkPad T490s",
> > > +               .matches = {
> > > +                       DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> > > +                       DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad
> > > T490s"),
> > > +               },
> > > +       },
> > > +       {}
> > > +};
> > > +
> > >  #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
> > >  static int has_hid(struct acpi_device *dev, const char *hid)
> > >  {
> > > @@ -192,6 +213,8 @@ static int tpm_tis_init(struct device *dev,
> > > struct tpm_info *tpm_info)
> > >         int irq = -1;
> > >         int rc;
> > > 
> > > +       dmi_check_system(tpm_tis_dmi_table);
> > > +
> > >         rc = check_acpi_tpm2(dev);
> > >         if (rc)
> > >                 return rc;
> > 
> > This looks OK to me with the caveat that anyone on one of these
> > systems
> > has no way to enable interrupts again if they think they have a
> > fixed
> > bios.  What about making interrupts a tristate with the default
> > value
> > -1?  Then in the dmi check, if we see -1 we set it to 0 but if we
> > see 1
> > (the user has specified interrupts=1 on the module insert line) we
> > leave it?
> > 
> > James
> 
> like this?

Yes, that works, I think.

Reviewed-by: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>

James


> diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
> index 0b214963539d..10c46cb26c5a 100644
> --- a/drivers/char/tpm/tpm_tis.c
> +++ b/drivers/char/tpm/tpm_tis.c
> @@ -27,6 +27,7 @@
>  #include <linux/of.h>
>  #include <linux/of_device.h>
>  #include <linux/kernel.h>
> +#include <linux/dmi.h>
>  #include "tpm.h"
>  #include "tpm_tis_core.h"
> 
> @@ -49,8 +50,8 @@ static inline struct tpm_tis_tcg_phy
> *to_tpm_tis_tcg_phy(struct tpm_tis_data *da
>         return container_of(data, struct tpm_tis_tcg_phy, priv);
>  }
> 
> -static bool interrupts = true;
> -module_param(interrupts, bool, 0444);
> +static int interrupts = -1;
> +module_param(interrupts, int, 0444);
>  MODULE_PARM_DESC(interrupts, "Enable interrupts");
> 
>  static bool itpm;
> @@ -63,6 +64,27 @@ module_param(force, bool, 0444);
>  MODULE_PARM_DESC(force, "Force device probe rather than using ACPI
> entry");
>  #endif
> 
> +static int tpm_tis_disable_irq(const struct dmi_system_id *d)
> +{
> +       pr_notice("tpm_tis: %s detected: disabling interrupts.\n", d-
> >ident);
> +       if (interrupts == -1)
> +               interrupts = 0;
> +
> +       return 0;
> +}
> +
> +static const struct dmi_system_id tpm_tis_dmi_table[] = {
> +       {
> +               .callback = tpm_tis_disable_irq,
> +               .ident = "ThinkPad T490s",
> +               .matches = {
> +                       DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> +                       DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad
> T490s"),
> +               },
> +       },
> +       {}
> +};
> +
>  #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
>  static int has_hid(struct acpi_device *dev, const char *hid)
>  {
> @@ -192,6 +214,8 @@ static int tpm_tis_init(struct device *dev,
> struct tpm_info *tpm_info)
>         int irq = -1;
>         int rc;
> 
> +       dmi_check_system(tpm_tis_dmi_table);
> +
>         rc = check_acpi_tpm2(dev);
>         if (rc)
>                 return rc;
> 





[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Linux Kernel]     [Linux Kernel Hardening]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux SCSI]

  Powered by Linux