Re: New warning: PRMT not present

[Paul Menzel]

Dear Aubrey,


Am 07.09.21 um 15:02 schrieb Aubrey Li:
> On 9/7/21 3:22 PM, Paul Menzel wrote:

> > Am 07.09.21 um 05:26 schrieb Aubrey Li:
> >
> > > On 9/6/21 10:15 PM, Paul Menzel wrote:
> >
> > > > Am 06.09.21 um 14:02 schrieb Rafael J. Wysocki:
> > > > > This should be addressed by commit 2bbfa0addd63 "ACPI: PRM: Deal with
> > > > > table not present or no module found", or yet another fix is needed.
> > > >
> > > > Linux still warns on my systems with Linux 5.14 and Linus’ master in QEMU i440fx and an Asus F2A85-M PRO.
> > >
> > > Does the following patch address your problem?
> >
> > Yes, it does. With this patch cherry-picked to my Linux tree, the warning is gone in QEMU.
> >
> >      qemu-system-x86_64 -kernel /dev/shm/bzImage -append "earlyprintk=serial,ttyS0,keep console=ttyS0,115200 console=tty0" -display none -serial stdio
> >
> > (I have to check my configuration, why normal serial console does not work in QEMU.)
> >
> > > ----------------------------------------------------------------------
> > >   From 52fda76410fcb7a3661687e960634d34fa44fb5f Mon Sep 17 00:00:00 2001
> > > From: Aubrey Li <aubrey.li@xxxxxxxxx>
> > > Date: Tue, 7 Sep 2021 11:06:59 +0800
> > > Subject: [PATCH] ACPI/RPM: Find PRMT table before parse it
> >
> > What does RPM mean?
>
> PRM, Platform Runtime Mechanism:
> https://uefi.org/sites/default/files/resources/Platform%20Runtime%20Mechanism%20-%20with%20legal%20notice.pdf

Ah, so just a typo in the prefix: RPM → PRM.

> > > Find and verify PRMT table before parse it, this eliminates a
> > > warning on machines without PRMT table.
> >
> > Please paste the warning for people grepping the commit messages.
> >
> >      ACPI: PRMT not present
>
> Nice suggestion.
>
> > > Signed-off-by: Aubrey Li <aubrey.li@xxxxxxxxxxxxxxx>
> > > ---
> > >    drivers/acpi/prmt.c | 10 +++++++++-
> > >    1 file changed, 9 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/acpi/prmt.c b/drivers/acpi/prmt.c
> > > index 1f6007a..89c22bc 100644
> > > --- a/drivers/acpi/prmt.c
> > > +++ b/drivers/acpi/prmt.c
> > > @@ -288,10 +288,18 @@ static acpi_status acpi_platformrt_space_handler(u32 function,
> > >      void __init init_prmt(void)
> > >    {
> > > +    struct acpi_table_header *tbl;
> > >        acpi_status status;
> > > -    int mc = acpi_table_parse_entries(ACPI_SIG_PRMT, sizeof(struct acpi_table_prmt) +
> > > +    int mc;
> > > +
> > > +    status = acpi_get_table(ACPI_SIG_PRMT, 0, &tbl);
> > > +    if (ACPI_FAILURE(status))
> > > +        return;
> > > +
> > > +    mc = acpi_table_parse_entries(ACPI_SIG_PRMT, sizeof(struct acpi_table_prmt) +
> > >                          sizeof (struct acpi_table_prmt_header),
> > >                          0, acpi_parse_prmt, 0);
> > > +    acpi_put_table(tbl);
> > >        /*
> > >         * Return immediately if PRMT table is not present or no PRM module found.
> > >         */
> >
> > Tested-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
>
> Thanks for testing, I'll send a formal patch to Rafael.

Thank you.


Kind regards,

Paul