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* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
       [not found]         ` <20161216143330.69e9c8ee@endymion>
@ 2016-12-17 10:57           ` Dave Young
  2019-09-06 19:00             ` Andy Shevchenko
  2020-01-20 12:19             ` Andy Shevchenko
  0 siblings, 2 replies; 13+ messages in thread
From: Dave Young @ 2016-12-17 10:57 UTC (permalink / raw)
  To: Jean Delvare
  Cc: Andy Shevchenko, kexec, Mika Westerberg, Eric Biederman,
	linux-kernel, linux-efi, matt, ard.biesheuvel

Ccing efi people.

On 12/16/16 at 02:33pm, Jean Delvare wrote:
> On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote:
> > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote:
> > > On 12/15/16 at 12:28pm, Jean Delvare wrote:
> > > > I am no kexec expert but this confuses me. Shouldn't the second
> > > > kernel have access to the EFI systab as the first kernel does? It
> > > > includes many more pointers than just ACPI and DMI tables, and it
> > > > would seem inconvenient to have to pass all these addresses
> > > > individually explicitly.
> > > 
> > > Yes, in modern linux kernel, kexec has the support for EFI, I think it
> > > should work naturally at least in x86_64.
> > 
> > Thanks for this good news!
> > 
> > Unfortunately Intel Galileo is 32-bit platform.
> 
> If it was done for X86_64 then maybe it can be generalized to X86?

For X86_64, we have a new way for efi runtime memmory mapping, in i386
code it still use old ioremap way. It is impossible to use same way as
the X86_64 since the virtual address space is limited.

But maybe for 32bit, kexec kernel can run in physical mode, but I'm not
sure, I would suggest Andy to do a test first with efi=noruntime for
kexec 2nd kernel.

Thanks
Dave

> 
> -- 
> Jean Delvare
> SUSE L3 Support

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2016-12-17 10:57           ` [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel Dave Young
@ 2019-09-06 19:00             ` Andy Shevchenko
  2020-01-20 12:19             ` Andy Shevchenko
  1 sibling, 0 replies; 13+ messages in thread
From: Andy Shevchenko @ 2019-09-06 19:00 UTC (permalink / raw)
  To: Dave Young
  Cc: Jean Delvare, kexec, Mika Westerberg, Eric Biederman,
	linux-kernel, linux-efi, matt, ard.biesheuvel

On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote:
> On 12/16/16 at 02:33pm, Jean Delvare wrote:
> > On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote:
> > > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote:
> > > > On 12/15/16 at 12:28pm, Jean Delvare wrote:
> > > > > I am no kexec expert but this confuses me. Shouldn't the second
> > > > > kernel have access to the EFI systab as the first kernel does? It
> > > > > includes many more pointers than just ACPI and DMI tables, and it
> > > > > would seem inconvenient to have to pass all these addresses
> > > > > individually explicitly.
> > > > 
> > > > Yes, in modern linux kernel, kexec has the support for EFI, I think it
> > > > should work naturally at least in x86_64.
> > > 
> > > Thanks for this good news!
> > > 
> > > Unfortunately Intel Galileo is 32-bit platform.
> > 
> > If it was done for X86_64 then maybe it can be generalized to X86?
> 
> For X86_64, we have a new way for efi runtime memmory mapping, in i386
> code it still use old ioremap way. It is impossible to use same way as
> the X86_64 since the virtual address space is limited.
> 
> But maybe for 32bit, kexec kernel can run in physical mode, but I'm not
> sure, I would suggest Andy to do a test first with efi=noruntime for
> kexec 2nd kernel.

Sorry for a delay.
Eventually I found time to check this.

Unfortunately the efi=noruntime didn't help:

# uname -a
Linux buildroot 5.3.0-rc7+ #17 Thu Sep 5 16:08:22 EEST 2019 i586 GNU/Linux
# dmidecode
# dmidecode 4.2
Scanning /dev/mem for entry point.
# No SMBIOS nor DMI entry point found, sorry.
#
# cat /proc/cmdline
... ignore_loglevel efi=noruntime earlycon=efifb acpi_rsdp=0xf01e014

So, I am all ears to anything else to try.

-- 
With Best Regards,
Andy Shevchenko



^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2016-12-17 10:57           ` [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel Dave Young
  2019-09-06 19:00             ` Andy Shevchenko
@ 2020-01-20 12:19             ` Andy Shevchenko
  2020-01-20 16:04               ` ebiederm
  1 sibling, 1 reply; 13+ messages in thread
From: Andy Shevchenko @ 2020-01-20 12:19 UTC (permalink / raw)
  To: Dave Young
  Cc: Jean Delvare, kexec, Mika Westerberg, Eric Biederman,
	linux-kernel, linux-efi, matt, ard.biesheuvel

On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote:
> Ccing efi people.
> 
> On 12/16/16 at 02:33pm, Jean Delvare wrote:
> > On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote:
> > > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote:
> > > > On 12/15/16 at 12:28pm, Jean Delvare wrote:
> > > > > I am no kexec expert but this confuses me. Shouldn't the second
> > > > > kernel have access to the EFI systab as the first kernel does? It
> > > > > includes many more pointers than just ACPI and DMI tables, and it
> > > > > would seem inconvenient to have to pass all these addresses
> > > > > individually explicitly.
> > > > 
> > > > Yes, in modern linux kernel, kexec has the support for EFI, I think it
> > > > should work naturally at least in x86_64.
> > > 
> > > Thanks for this good news!
> > > 
> > > Unfortunately Intel Galileo is 32-bit platform.
> > 
> > If it was done for X86_64 then maybe it can be generalized to X86?
> 
> For X86_64, we have a new way for efi runtime memmory mapping, in i386
> code it still use old ioremap way. It is impossible to use same way as
> the X86_64 since the virtual address space is limited.
> 
> But maybe for 32bit, kexec kernel can run in physical mode, but I'm not
> sure, I would suggest Andy to do a test first with efi=noruntime for
> kexec 2nd kernel.

Guys, it was quite a long no hear from you. As I told you the proposed work
around didn't help. Today I found that Microsoft Surface 3 also affected
by this.

Can we apply these patches for now until you will find better solution?

P.S. I may resend them rebased on recent vanilla.

-- 
With Best Regards,
Andy Shevchenko



^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-20 12:19             ` Andy Shevchenko
@ 2020-01-20 16:04               ` ebiederm
  2020-01-20 21:42                 ` Jean Delvare
  2020-01-20 22:31                 ` Andy Shevchenko
  0 siblings, 2 replies; 13+ messages in thread
From: ebiederm @ 2020-01-20 16:04 UTC (permalink / raw)
  To: Andy Shevchenko
  Cc: Dave Young, linux-efi, ard.biesheuvel, matt, kexec, linux-kernel,
	Mika Westerberg, Jean Delvare

Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes:

> On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote:
>> Ccing efi people.
>> 
>> On 12/16/16 at 02:33pm, Jean Delvare wrote:
>> > On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote:
>> > > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote:
>> > > > On 12/15/16 at 12:28pm, Jean Delvare wrote:
>> > > > > I am no kexec expert but this confuses me. Shouldn't the second
>> > > > > kernel have access to the EFI systab as the first kernel does? It
>> > > > > includes many more pointers than just ACPI and DMI tables, and it
>> > > > > would seem inconvenient to have to pass all these addresses
>> > > > > individually explicitly.
>> > > > 
>> > > > Yes, in modern linux kernel, kexec has the support for EFI, I think it
>> > > > should work naturally at least in x86_64.
>> > > 
>> > > Thanks for this good news!
>> > > 
>> > > Unfortunately Intel Galileo is 32-bit platform.
>> > 
>> > If it was done for X86_64 then maybe it can be generalized to X86?
>> 
>> For X86_64, we have a new way for efi runtime memmory mapping, in i386
>> code it still use old ioremap way. It is impossible to use same way as
>> the X86_64 since the virtual address space is limited.
>> 
>> But maybe for 32bit, kexec kernel can run in physical mode, but I'm not
>> sure, I would suggest Andy to do a test first with efi=noruntime for
>> kexec 2nd kernel.
>
> Guys, it was quite a long no hear from you. As I told you the proposed work
> around didn't help. Today I found that Microsoft Surface 3 also affected
> by this.
>
> Can we apply these patches for now until you will find better
> solution?

Not a chance.  The patches don't apply to any kernel in the git history.

Which may be part of your problem.  You are or at least were running
with code that has not been merged upstream.

> P.S. I may resend them rebased on recent vanilla.

Second.  I looked at your test results and they don't directly make
sense.  dmidecode bypasses the kernel completely or it did last time
I looked so I don't know why you would be using that to test if
something in the kernel is working.

However dmidecode failing suggests that the actual problem is something
in the first kernel is stomping the dmi tables.

Adding a command line option won't fix stomped tables.

So what I would suggest is:
a) Verify that dmidecode works before kexec.
b) Test to see if dmidecode works after kexec.
c) Once (a) shows that dmidecode works and (b) shows that dmidecode
   fails figure out what is stomping your dmi tables during or before
   kexec and that is what should get fixed.

Now using a non-efi method of dmi detection relies on the
tables being between 0xF0000 and 0x10000. AKA the last 64K
of the first 1MiB of memory.  You might check to see if your
dmi tables are in that address range.

Otherwise I suspect the good solution is to give efi it's own page
tables in the kernel and switch to it whenever efi functions are called.

But on 32bit the Linux kernel has historically been just fine directly
accessing the hardware, and ignoring efi and all of the other BIOS's.
So if that doesn't work on Intel Galileo that is probably a firmware
problem.

Eric


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-20 16:04               ` ebiederm
@ 2020-01-20 21:42                 ` Jean Delvare
  2020-01-20 21:55                   ` Andy Shevchenko
  2020-01-20 22:31                 ` Andy Shevchenko
  1 sibling, 1 reply; 13+ messages in thread
From: Jean Delvare @ 2020-01-20 21:42 UTC (permalink / raw)
  To: ebiederm
  Cc: Andy Shevchenko, Dave Young, linux-efi, ard.biesheuvel, matt,
	kexec, linux-kernel, Mika Westerberg

On Mon, 20 Jan 2020 10:04:04 -0600, Eric W. Biederman wrote:
> Second.  I looked at your test results and they don't directly make
> sense.  dmidecode bypasses the kernel completely or it did last time
> I looked so I don't know why you would be using that to test if
> something in the kernel is working.

That must have been long ago. A recent version of dmidecode (>= 3.0)
running on a recent kernel
(>= d7f96f97c4031fa4ffdb7801f9aae23e96170a6f, v4.2) will read the DMI
data from /sys/firmware/dmi/tables, so it is very much relying on the
kernel doing the right thing. If not, it will still try to fallback to
reading from /dev/mem directly on certain architectures. You can force
that old method with --no-sysfs.

Hope that helps,
-- 
Jean Delvare
SUSE L3 Support

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-20 21:42                 ` Jean Delvare
@ 2020-01-20 21:55                   ` Andy Shevchenko
  2020-01-21  9:03                     ` Jean Delvare
  0 siblings, 1 reply; 13+ messages in thread
From: Andy Shevchenko @ 2020-01-20 21:55 UTC (permalink / raw)
  To: Jean Delvare
  Cc: Eric W. Biederman, Andy Shevchenko, Dave Young, linux-efi,
	Ard Biesheuvel, Matt Fleming, kexec, Linux Kernel Mailing List,
	Mika Westerberg

On Mon, Jan 20, 2020 at 11:44 PM Jean Delvare <jdelvare@suse.de> wrote:
>
> On Mon, 20 Jan 2020 10:04:04 -0600, Eric W. Biederman wrote:
> > Second.  I looked at your test results and they don't directly make
> > sense.  dmidecode bypasses the kernel completely or it did last time
> > I looked so I don't know why you would be using that to test if
> > something in the kernel is working.
>
> That must have been long ago. A recent version of dmidecode (>= 3.0)
> running on a recent kernel
> (>= d7f96f97c4031fa4ffdb7801f9aae23e96170a6f, v4.2) will read the DMI
> data from /sys/firmware/dmi/tables, so it is very much relying on the
> kernel doing the right thing. If not, it will still try to fallback to
> reading from /dev/mem directly on certain architectures. You can force
> that old method with --no-sysfs.
>
> Hope that helps,

I don't understand how it possible can help for in-kernel code, like
DMI quirks in a drivers.

-- 
With Best Regards,
Andy Shevchenko

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-20 16:04               ` ebiederm
  2020-01-20 21:42                 ` Jean Delvare
@ 2020-01-20 22:31                 ` Andy Shevchenko
  2020-01-20 23:18                   ` Ard Biesheuvel
  1 sibling, 1 reply; 13+ messages in thread
From: Andy Shevchenko @ 2020-01-20 22:31 UTC (permalink / raw)
  To: Eric W. Biederman
  Cc: Andy Shevchenko, Dave Young, linux-efi, Ard Biesheuvel,
	Matt Fleming, kexec, Linux Kernel Mailing List, Mika Westerberg,
	Jean Delvare

On Mon, Jan 20, 2020 at 9:28 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes:
> > On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote:
> >> Ccing efi people.
> >>
> >> On 12/16/16 at 02:33pm, Jean Delvare wrote:
> >> > On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote:
> >> > > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote:
> >> > > > On 12/15/16 at 12:28pm, Jean Delvare wrote:
> >> > > > > I am no kexec expert but this confuses me. Shouldn't the second
> >> > > > > kernel have access to the EFI systab as the first kernel does? It
> >> > > > > includes many more pointers than just ACPI and DMI tables, and it
> >> > > > > would seem inconvenient to have to pass all these addresses
> >> > > > > individually explicitly.
> >> > > >
> >> > > > Yes, in modern linux kernel, kexec has the support for EFI, I think it
> >> > > > should work naturally at least in x86_64.
> >> > >
> >> > > Thanks for this good news!
> >> > >
> >> > > Unfortunately Intel Galileo is 32-bit platform.
> >> >
> >> > If it was done for X86_64 then maybe it can be generalized to X86?
> >>
> >> For X86_64, we have a new way for efi runtime memmory mapping, in i386
> >> code it still use old ioremap way. It is impossible to use same way as
> >> the X86_64 since the virtual address space is limited.
> >>
> >> But maybe for 32bit, kexec kernel can run in physical mode, but I'm not
> >> sure, I would suggest Andy to do a test first with efi=noruntime for
> >> kexec 2nd kernel.
> >
> > Guys, it was quite a long no hear from you. As I told you the proposed work
> > around didn't help. Today I found that Microsoft Surface 3 also affected
> > by this.
> >
> > Can we apply these patches for now until you will find better
> > solution?
>
> Not a chance.  The patches don't apply to any kernel in the git history.
>
> Which may be part of your problem.  You are or at least were running
> with code that has not been merged upstream.

It's done against linux-next.
Applied clearly. (Not the version in this more than yearly old series
of course, that's why I told I can resend)

> > P.S. I may resend them rebased on recent vanilla.
>
> Second.  I looked at your test results and they don't directly make
> sense.  dmidecode bypasses the kernel completely or it did last time
> I looked so I don't know why you would be using that to test if
> something in the kernel is working.
>
> However dmidecode failing suggests that the actual problem is something
> in the first kernel is stomping the dmi tables.

See below.

> Adding a command line option won't fix stomped tables.

It provides a mechanism, which seems to be absent, to the second
kernel to know where to look for SMBIOS tables.

> So what I would suggest is:
> a) Verify that dmidecode works before kexec.

Yes, it does.

> b) Test to see if dmidecode works after kexec.

No, it doesn't.

> c) Once (a) shows that dmidecode works and (b) shows that dmidecode
>    fails figure out what is stomping your dmi tables during or before
>    kexec and that is what should get fixed.

The problem here as I can see it that EFI and kexec protocols are not
friendly to each other.
I'm not an expert in either. That's why I'm asking for possible
solutions. And this needs to be done in kernel to allow drivers to
work.

Does the

commit 4996c02306a25def1d352ec8e8f48895bbc7dea9
Author: Takao Indoh <indou.takao@jp.fujitsu.com>
Date:   Thu Jul 14 18:05:21 2011 -0400

    ACPI: introduce "acpi_rsdp=" parameter for kdump

description shed a light on this?

> Now using a non-efi method of dmi detection relies on the
> tables being between 0xF0000 and 0x10000. AKA the last 64K
> of the first 1MiB of memory.  You might check to see if your
> dmi tables are in that address range.

# dmidecode --no-sysfs
# dmidecode 3.2
Scanning /dev/mem for entry point.
# No SMBIOS nor DMI entry point found, sorry.

=== with patch applied ===
# dmidecode
...
        Release Date: 03/10/2015
...

>
> Otherwise I suspect the good solution is to give efi it's own page
> tables in the kernel and switch to it whenever efi functions are called.
>

> But on 32bit the Linux kernel has historically been just fine directly
> accessing the hardware, and ignoring efi and all of the other BIOS's.

It seems not only for 32-bit Linux kernel anymore. MS Surface 3 runs
64-bit code.

> So if that doesn't work on Intel Galileo that is probably a firmware
> problem.

It's not only about Galileo anymore.

-- 
With Best Regards,
Andy Shevchenko

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-20 22:31                 ` Andy Shevchenko
@ 2020-01-20 23:18                   ` Ard Biesheuvel
  2020-01-21 15:37                     ` Andy Shevchenko
  0 siblings, 1 reply; 13+ messages in thread
From: Ard Biesheuvel @ 2020-01-20 23:18 UTC (permalink / raw)
  To: Andy Shevchenko
  Cc: Eric W. Biederman, Andy Shevchenko, Dave Young, linux-efi,
	Matt Fleming, Kexec Mailing List, Linux Kernel Mailing List,
	Mika Westerberg, Jean Delvare

On Mon, 20 Jan 2020 at 23:31, Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
>
> On Mon, Jan 20, 2020 at 9:28 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
> > Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes:
> > > On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote:
> > >> Ccing efi people.
> > >>
> > >> On 12/16/16 at 02:33pm, Jean Delvare wrote:
> > >> > On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote:
> > >> > > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote:
> > >> > > > On 12/15/16 at 12:28pm, Jean Delvare wrote:
> > >> > > > > I am no kexec expert but this confuses me. Shouldn't the second
> > >> > > > > kernel have access to the EFI systab as the first kernel does? It
> > >> > > > > includes many more pointers than just ACPI and DMI tables, and it
> > >> > > > > would seem inconvenient to have to pass all these addresses
> > >> > > > > individually explicitly.
> > >> > > >
> > >> > > > Yes, in modern linux kernel, kexec has the support for EFI, I think it
> > >> > > > should work naturally at least in x86_64.
> > >> > >
> > >> > > Thanks for this good news!
> > >> > >
> > >> > > Unfortunately Intel Galileo is 32-bit platform.
> > >> >
> > >> > If it was done for X86_64 then maybe it can be generalized to X86?
> > >>
> > >> For X86_64, we have a new way for efi runtime memmory mapping, in i386
> > >> code it still use old ioremap way. It is impossible to use same way as
> > >> the X86_64 since the virtual address space is limited.
> > >>
> > >> But maybe for 32bit, kexec kernel can run in physical mode, but I'm not
> > >> sure, I would suggest Andy to do a test first with efi=noruntime for
> > >> kexec 2nd kernel.
> > >
> > > Guys, it was quite a long no hear from you. As I told you the proposed work
> > > around didn't help. Today I found that Microsoft Surface 3 also affected
> > > by this.
> > >
> > > Can we apply these patches for now until you will find better
> > > solution?
> >
> > Not a chance.  The patches don't apply to any kernel in the git history.
> >
> > Which may be part of your problem.  You are or at least were running
> > with code that has not been merged upstream.
>
> It's done against linux-next.
> Applied clearly. (Not the version in this more than yearly old series
> of course, that's why I told I can resend)
>
> > > P.S. I may resend them rebased on recent vanilla.
> >
> > Second.  I looked at your test results and they don't directly make
> > sense.  dmidecode bypasses the kernel completely or it did last time
> > I looked so I don't know why you would be using that to test if
> > something in the kernel is working.
> >
> > However dmidecode failing suggests that the actual problem is something
> > in the first kernel is stomping the dmi tables.
>
> See below.
>
> > Adding a command line option won't fix stomped tables.
>
> It provides a mechanism, which seems to be absent, to the second
> kernel to know where to look for SMBIOS tables.
>
> > So what I would suggest is:
> > a) Verify that dmidecode works before kexec.
>
> Yes, it does.
>
> > b) Test to see if dmidecode works after kexec.
>
> No, it doesn't.
>
> > c) Once (a) shows that dmidecode works and (b) shows that dmidecode
> >    fails figure out what is stomping your dmi tables during or before
> >    kexec and that is what should get fixed.
>
> The problem here as I can see it that EFI and kexec protocols are not
> friendly to each other.
> I'm not an expert in either. That's why I'm asking for possible
> solutions. And this needs to be done in kernel to allow drivers to
> work.
>
> Does the
>
> commit 4996c02306a25def1d352ec8e8f48895bbc7dea9
> Author: Takao Indoh <indou.takao@jp.fujitsu.com>
> Date:   Thu Jul 14 18:05:21 2011 -0400
>
>     ACPI: introduce "acpi_rsdp=" parameter for kdump
>
> description shed a light on this?
>
> > Now using a non-efi method of dmi detection relies on the
> > tables being between 0xF0000 and 0x10000. AKA the last 64K
> > of the first 1MiB of memory.  You might check to see if your
> > dmi tables are in that address range.
>
> # dmidecode --no-sysfs
> # dmidecode 3.2
> Scanning /dev/mem for entry point.
> # No SMBIOS nor DMI entry point found, sorry.
>
> === with patch applied ===
> # dmidecode
> ...
>         Release Date: 03/10/2015
> ...
>
> >
> > Otherwise I suspect the good solution is to give efi it's own page
> > tables in the kernel and switch to it whenever efi functions are called.
> >
>
> > But on 32bit the Linux kernel has historically been just fine directly
> > accessing the hardware, and ignoring efi and all of the other BIOS's.
>
> It seems not only for 32-bit Linux kernel anymore. MS Surface 3 runs
> 64-bit code.
>
> > So if that doesn't work on Intel Galileo that is probably a firmware
> > problem.
>
> It's not only about Galileo anymore.
>

Looking at the x86 kexec EFI code, it seems that it has special
handling for the legacy SMBIOS table address, but not for the SMBIOS3
table address, which was introduced to accommodate SMBIOS tables
living in memory that is not 32-bit addressable.

Could anyone check whether these systems provide SMBIOS 3.0 tables,
and whether their address gets virtually remapped at ExitBootServices?

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-20 21:55                   ` Andy Shevchenko
@ 2020-01-21  9:03                     ` Jean Delvare
  2020-01-21 16:29                       ` ebiederm
  0 siblings, 1 reply; 13+ messages in thread
From: Jean Delvare @ 2020-01-21  9:03 UTC (permalink / raw)
  To: Andy Shevchenko
  Cc: Eric W. Biederman, Andy Shevchenko, Dave Young, linux-efi,
	Ard Biesheuvel, Matt Fleming, kexec, Linux Kernel Mailing List,
	Mika Westerberg

On Mon, 20 Jan 2020 23:55:43 +0200, Andy Shevchenko wrote:
> On Mon, Jan 20, 2020 at 11:44 PM Jean Delvare <jdelvare@suse.de> wrote:
> >
> > On Mon, 20 Jan 2020 10:04:04 -0600, Eric W. Biederman wrote:  
> > > Second.  I looked at your test results and they don't directly make
> > > sense.  dmidecode bypasses the kernel completely or it did last time
> > > I looked so I don't know why you would be using that to test if
> > > something in the kernel is working.  
> >
> > That must have been long ago. A recent version of dmidecode (>= 3.0)
> > running on a recent kernel  
> > (>= d7f96f97c4031fa4ffdb7801f9aae23e96170a6f, v4.2) will read the DMI  
> > data from /sys/firmware/dmi/tables, so it is very much relying on the
> > kernel doing the right thing. If not, it will still try to fallback to
> > reading from /dev/mem directly on certain architectures. You can force
> > that old method with --no-sysfs.
> >
> > Hope that helps,  
> 
> I don't understand how it possible can help for in-kernel code, like
> DMI quirks in a drivers.

OK, just ignore me then, probably I misunderstood the point made by
Eric.

-- 
Jean Delvare
SUSE L3 Support

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-20 23:18                   ` Ard Biesheuvel
@ 2020-01-21 15:37                     ` Andy Shevchenko
  2020-01-21 17:17                       ` ebiederm
  0 siblings, 1 reply; 13+ messages in thread
From: Andy Shevchenko @ 2020-01-21 15:37 UTC (permalink / raw)
  To: Ard Biesheuvel
  Cc: Eric W. Biederman, Dave Young, linux-efi, Matt Fleming,
	Kexec Mailing List, Linux Kernel Mailing List, Mika Westerberg,
	Jean Delvare

On Tue, Jan 21, 2020 at 12:18:03AM +0100, Ard Biesheuvel wrote:
> On Mon, 20 Jan 2020 at 23:31, Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
> > On Mon, Jan 20, 2020 at 9:28 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
> > > Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes:
> > > > On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote:

...

> > > > Can we apply these patches for now until you will find better
> > > > solution?
> > >
> > > Not a chance.  The patches don't apply to any kernel in the git history.
> > >
> > > Which may be part of your problem.  You are or at least were running
> > > with code that has not been merged upstream.
> >
> > It's done against linux-next.
> > Applied clearly. (Not the version in this more than yearly old series
> > of course, that's why I told I can resend)
> >
> > > > P.S. I may resend them rebased on recent vanilla.
> > >
> > > Second.  I looked at your test results and they don't directly make
> > > sense.  dmidecode bypasses the kernel completely or it did last time
> > > I looked so I don't know why you would be using that to test if
> > > something in the kernel is working.
> > >
> > > However dmidecode failing suggests that the actual problem is something
> > > in the first kernel is stomping the dmi tables.
> >
> > See below.
> >
> > > Adding a command line option won't fix stomped tables.
> >
> > It provides a mechanism, which seems to be absent, to the second
> > kernel to know where to look for SMBIOS tables.
> >
> > > So what I would suggest is:
> > > a) Verify that dmidecode works before kexec.
> >
> > Yes, it does.
> >
> > > b) Test to see if dmidecode works after kexec.
> >
> > No, it doesn't.
> >
> > > c) Once (a) shows that dmidecode works and (b) shows that dmidecode
> > >    fails figure out what is stomping your dmi tables during or before
> > >    kexec and that is what should get fixed.
> >
> > The problem here as I can see it that EFI and kexec protocols are not
> > friendly to each other.
> > I'm not an expert in either. That's why I'm asking for possible
> > solutions. And this needs to be done in kernel to allow drivers to
> > work.
> >
> > Does the
> >
> > commit 4996c02306a25def1d352ec8e8f48895bbc7dea9
> > Author: Takao Indoh <indou.takao@jp.fujitsu.com>
> > Date:   Thu Jul 14 18:05:21 2011 -0400
> >
> >     ACPI: introduce "acpi_rsdp=" parameter for kdump
> >
> > description shed a light on this?
> >
> > > Now using a non-efi method of dmi detection relies on the
> > > tables being between 0xF0000 and 0x10000. AKA the last 64K
> > > of the first 1MiB of memory.  You might check to see if your
> > > dmi tables are in that address range.
> >
> > # dmidecode --no-sysfs
> > # dmidecode 3.2
> > Scanning /dev/mem for entry point.
> > # No SMBIOS nor DMI entry point found, sorry.
> >
> > === with patch applied ===
> > # dmidecode
> > ...
> >         Release Date: 03/10/2015
> > ...
> >
> > >
> > > Otherwise I suspect the good solution is to give efi it's own page
> > > tables in the kernel and switch to it whenever efi functions are called.
> > >
> >
> > > But on 32bit the Linux kernel has historically been just fine directly
> > > accessing the hardware, and ignoring efi and all of the other BIOS's.
> >
> > It seems not only for 32-bit Linux kernel anymore. MS Surface 3 runs
> > 64-bit code.
> >
> > > So if that doesn't work on Intel Galileo that is probably a firmware
> > > problem.
> >
> > It's not only about Galileo anymore.
> >
> 
> Looking at the x86 kexec EFI code, it seems that it has special
> handling for the legacy SMBIOS table address, but not for the SMBIOS3
> table address, which was introduced to accommodate SMBIOS tables
> living in memory that is not 32-bit addressable.
> 
> Could anyone check whether these systems provide SMBIOS 3.0 tables,
> and whether their address gets virtually remapped at ExitBootServices?

On Microsoft Surface 3 tablet:

=== First kernel ===

# uname -a

(Previously reported issue on)
Linux buildroot 4.13.0+ #39 SMP Tue Sep 5 14:58:23 EEST 2017 x86_64 GNU/Linux

(Updated today to)
Linux buildroot 5.4.0+ #2 SMP Tue Nov 26 15:36:31 EET 2019 x86_64 GNU/Linux

# ls -l /sys/firmware/dmi/tables/
total 0
-r--------    1 root     root           825 Jan 21 15:41 DMI
-r--------    1 root     root            31 Jan 21 15:41 smbios_entry_point

# od -Ax -tx1 /sys/firmware/dmi/tables/smbios_entry_point
000000 5f 53 4d 5f 0f 1f 02 08 6a 00 00 00 00 00 00 00
000010 5f 44 4d 49 5f e0 39 03 00 40 5b 7b 0f 00 27
00001f

# dmesg | grep -i dmi
[    0.000000] DMI: Microsoft Corporation Surface 3/Surface 3, BIOS 1.50410.78 03/10/2015
[    0.403058] ACPI: Added _OSI(Linux-Lenovo-NV-HDMI-Audio)

# dmesg | grep -i smb
[    0.000000] efi:  ESRT=0x7b7c6c98  ACPI=0x7ad5a000  ACPI 2.0=0x7ad5a000  SMBIOS=0x7b5f7d18
[    0.000000] SMBIOS 2.8 present.

=== kexec'ed kernel ===
# uname -a
(in both cases, see above `uname -a`, the same version)
Linux buildroot 5.5.0-rc7+ #161 SMP Tue Jan 21 15:50:02 EET 2020 x86_64 GNU/Linux

# dmidecode
# dmidecode 3.2
	Scanning /dev/mem for entry point.
# No SMBIOS nor DMI entry point found, sorry.

# dmidecode --no-sysfs
# dmidecode 3.2
	Scanning /dev/mem for entry point.
# No SMBIOS nor DMI entry point found, sorry.


-- 
With Best Regards,
Andy Shevchenko



^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-21  9:03                     ` Jean Delvare
@ 2020-01-21 16:29                       ` ebiederm
  2020-01-21 17:24                         ` Andy Shevchenko
  0 siblings, 1 reply; 13+ messages in thread
From: ebiederm @ 2020-01-21 16:29 UTC (permalink / raw)
  To: Jean Delvare
  Cc: Andy Shevchenko, Andy Shevchenko, Dave Young, linux-efi,
	Ard Biesheuvel, Matt Fleming, kexec, Linux Kernel Mailing List,
	Mika Westerberg

Jean Delvare <jdelvare@suse.de> writes:

> On Mon, 20 Jan 2020 23:55:43 +0200, Andy Shevchenko wrote:
>> On Mon, Jan 20, 2020 at 11:44 PM Jean Delvare <jdelvare@suse.de> wrote:
>> >
>> > On Mon, 20 Jan 2020 10:04:04 -0600, Eric W. Biederman wrote:  
>> > > Second.  I looked at your test results and they don't directly make
>> > > sense.  dmidecode bypasses the kernel completely or it did last time
>> > > I looked so I don't know why you would be using that to test if
>> > > something in the kernel is working.  
>> >
>> > That must have been long ago. A recent version of dmidecode (>= 3.0)
>> > running on a recent kernel  
>> > (>= d7f96f97c4031fa4ffdb7801f9aae23e96170a6f, v4.2) will read the DMI  
>> > data from /sys/firmware/dmi/tables, so it is very much relying on the
>> > kernel doing the right thing. If not, it will still try to fallback to
>> > reading from /dev/mem directly on certain architectures. You can force
>> > that old method with --no-sysfs.
>> >
>> > Hope that helps,  
>> 
>> I don't understand how it possible can help for in-kernel code, like
>> DMI quirks in a drivers.
>
> OK, just ignore me then, probably I misunderstood the point made by
> Eric.

No.  I just haven't dived into this area of code in a long time.

It seems a little indirect to use dmidecode as the test to see if the
kernel has the pointer to the dmitables, but with the knowledge you
provided it seems like a perfectly valid test.

Eric


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-21 15:37                     ` Andy Shevchenko
@ 2020-01-21 17:17                       ` ebiederm
  0 siblings, 0 replies; 13+ messages in thread
From: ebiederm @ 2020-01-21 17:17 UTC (permalink / raw)
  To: Andy Shevchenko
  Cc: Ard Biesheuvel, Dave Young, linux-efi, Matt Fleming,
	Kexec Mailing List, Linux Kernel Mailing List, Mika Westerberg,
	Jean Delvare

Andy Shevchenko <andy.shevchenko@gmail.com> writes:

> On Tue, Jan 21, 2020 at 12:18:03AM +0100, Ard Biesheuvel wrote:
>> On Mon, 20 Jan 2020 at 23:31, Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
>> > On Mon, Jan 20, 2020 at 9:28 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
>> > > Andy Shevchenko <andriy.shevchenko@linux.intel.com> writes:
>> > > > On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote:
>
> ...
>
>> > > > Can we apply these patches for now until you will find better
>> > > > solution?
>> > >
>> > > Not a chance.  The patches don't apply to any kernel in the git history.
>> > >
>> > > Which may be part of your problem.  You are or at least were running
>> > > with code that has not been merged upstream.
>> >
>> > It's done against linux-next.
>> > Applied clearly. (Not the version in this more than yearly old series
>> > of course, that's why I told I can resend)
>> >
>> > > > P.S. I may resend them rebased on recent vanilla.
>> > >
>> > > Second.  I looked at your test results and they don't directly make
>> > > sense.  dmidecode bypasses the kernel completely or it did last time
>> > > I looked so I don't know why you would be using that to test if
>> > > something in the kernel is working.
>> > >
>> > > However dmidecode failing suggests that the actual problem is something
>> > > in the first kernel is stomping the dmi tables.
>> >
>> > See below.
>> >
>> > > Adding a command line option won't fix stomped tables.
>> >
>> > It provides a mechanism, which seems to be absent, to the second
>> > kernel to know where to look for SMBIOS tables.
>> >
>> > > So what I would suggest is:
>> > > a) Verify that dmidecode works before kexec.
>> >
>> > Yes, it does.
>> >
>> > > b) Test to see if dmidecode works after kexec.
>> >
>> > No, it doesn't.
>> >
>> > > c) Once (a) shows that dmidecode works and (b) shows that dmidecode
>> > >    fails figure out what is stomping your dmi tables during or before
>> > >    kexec and that is what should get fixed.
>> >
>> > The problem here as I can see it that EFI and kexec protocols are not
>> > friendly to each other.
>> > I'm not an expert in either. That's why I'm asking for possible
>> > solutions. And this needs to be done in kernel to allow drivers to
>> > work.
>> >
>> > Does the
>> >
>> > commit 4996c02306a25def1d352ec8e8f48895bbc7dea9
>> > Author: Takao Indoh <indou.takao@jp.fujitsu.com>
>> > Date:   Thu Jul 14 18:05:21 2011 -0400
>> >
>> >     ACPI: introduce "acpi_rsdp=" parameter for kdump
>> >
>> > description shed a light on this?
>> >
>> > > Now using a non-efi method of dmi detection relies on the
>> > > tables being between 0xF0000 and 0x10000. AKA the last 64K
>> > > of the first 1MiB of memory.  You might check to see if your
>> > > dmi tables are in that address range.
>> >
>> > # dmidecode --no-sysfs
>> > # dmidecode 3.2
>> > Scanning /dev/mem for entry point.
>> > # No SMBIOS nor DMI entry point found, sorry.
>> >
>> > === with patch applied ===
>> > # dmidecode
>> > ...
>> >         Release Date: 03/10/2015
>> > ...
>> >
>> > >
>> > > Otherwise I suspect the good solution is to give efi it's own page
>> > > tables in the kernel and switch to it whenever efi functions are called.
>> > >
>> >
>> > > But on 32bit the Linux kernel has historically been just fine directly
>> > > accessing the hardware, and ignoring efi and all of the other BIOS's.
>> >
>> > It seems not only for 32-bit Linux kernel anymore. MS Surface 3 runs
>> > 64-bit code.
>> >
>> > > So if that doesn't work on Intel Galileo that is probably a firmware
>> > > problem.
>> >
>> > It's not only about Galileo anymore.
>> >
>> 
>> Looking at the x86 kexec EFI code, it seems that it has special
>> handling for the legacy SMBIOS table address, but not for the SMBIOS3
>> table address, which was introduced to accommodate SMBIOS tables
>> living in memory that is not 32-bit addressable.
>> 
>> Could anyone check whether these systems provide SMBIOS 3.0 tables,
>> and whether their address gets virtually remapped at ExitBootServices?
>
> On Microsoft Surface 3 tablet:
>
> === First kernel ===
>
> # uname -a
>
> (Previously reported issue on)
> Linux buildroot 4.13.0+ #39 SMP Tue Sep 5 14:58:23 EEST 2017 x86_64 GNU/Linux
>
> (Updated today to)
> Linux buildroot 5.4.0+ #2 SMP Tue Nov 26 15:36:31 EET 2019 x86_64 GNU/Linux
>
> # ls -l /sys/firmware/dmi/tables/
> total 0
> -r--------    1 root     root           825 Jan 21 15:41 DMI
> -r--------    1 root     root            31 Jan 21 15:41 smbios_entry_point
>
> # od -Ax -tx1 /sys/firmware/dmi/tables/smbios_entry_point
> 000000 5f 53 4d 5f 0f 1f 02 08 6a 00 00 00 00 00 00 00
> 000010 5f 44 4d 49 5f e0 39 03 00 40 5b 7b 0f 00 27
> 00001f
>
> # dmesg | grep -i dmi
> [    0.000000] DMI: Microsoft Corporation Surface 3/Surface 3, BIOS 1.50410.78 03/10/2015
> [    0.403058] ACPI: Added _OSI(Linux-Lenovo-NV-HDMI-Audio)
>
> # dmesg | grep -i smb
> [    0.000000] efi:  ESRT=0x7b7c6c98  ACPI=0x7ad5a000  ACPI 2.0=0x7ad5a000  SMBIOS=0x7b5f7d18
> [    0.000000] SMBIOS 2.8 present.
>
> === kexec'ed kernel ===
> # uname -a
> (in both cases, see above `uname -a`, the same version)
> Linux buildroot 5.5.0-rc7+ #161 SMP Tue Jan 21 15:50:02 EET 2020 x86_64 GNU/Linux
>
> # dmidecode
> # dmidecode 3.2
> 	Scanning /dev/mem for entry point.
> # No SMBIOS nor DMI entry point found, sorry.
>
> # dmidecode --no-sysfs
> # dmidecode 3.2
> 	Scanning /dev/mem for entry point.
> # No SMBIOS nor DMI entry point found, sorry.

This sounds like at least something of a different issue, with similar
symptoms.

I don't think it is fundamentally wrong to pass the location of the dmi
tables in a command line option.  If you can build that command line
option independent of kexec and it takes practically no maintenance then
it does not harm, and can be used as a debug option by others.

My primary concern with your original patch is because it did not
apply to any version of the kernel in Linus's git tree that it had not
been tested on any code.



That said let me lay some background on kexec and efi so we can
have a productive conversation about how to maintain their cooperation
in the long term.  I am going to do this from memory so please forgive
me where I get my details slightly off.

EFI has two interesting calls for an operating system.

SetVirtualMap
ExitBootServices

The law of large numbers strongly suggests that when it comes to
emperical testing any interface that is not so heavily used it will fail
to boot all operating systems if it doesn't work will have at least one
broken implementation somewhere.  A bug so bad nothing can boot means
the hardware is unshippable and so will not be seen in the wild.  As
firmware is essentially fixed once a machine ships this means that all
firmware problems have to be dealt with by the boot loader and the
operating system.


SetVirtualMap by design can be called only once, which is problematic
when you are switching operating systems on a running system (kexec).
Last I was paying attention there were also systems discovered that
won't work if SetVirtualMap is not called at all.  I believe the
solution adopted for x86_64 was to always map EFI at the same location
in the page tables and only call SetVirtualMap the first time.


ExitBootSerives is similarly challenging as it can only be called once,
and there are systems that get it wrong if you call it at all.  Even if
ExitBootServices works you can't depend on any of the boot services for
the second kernel.



There are two primary uses for kexec.  To use the first kernel as a boot
loader in which case it is desiable for everything to work after kexec
is called.  To use the second kernel as something to capture a crash
dump in which case simply a best effor is needed and failing cleanly
if something won't work properly.


You are running interactive commands so I presume you are wanting to use
kexec as a bootloader.


I don't know where things are now but for a while was no desire to
address the concerns of people using kexec by the folks implementing EFI
or the folks implementing EFI support in the kernel.  But that is
probably how we got into a situation where efi support does not work
cleanly.

EFI choosing to place firwmare tables in somewhere besides their
architecturally defined location does not help.

I don't practically have a system with EFI so I have not personally
cared to fix any of the problems.


My sense is that for making EFI calls from any linux kernel should be
isolated in it's own page table, so isolate as much as possible any
EFI bugs from the rest of the kernel.  That is probably also needed to
provide a guard against speculative execution side channel attacks.



I can see doing some work to get EFI functional after kexec if it isn't
but at the same time I am not a fan of performing any unnecessary
firmware calls.  Someone sometime will implement one wrong, and it will
be a headache for everyone until it is removed.


By the same token I don't understand the problem with DMI not working.
As I recall all the linux kernel really uses DMI for is to decide which
quirks to apply.  It might be better just to pass a board name string
on the kernel command line, and use that string for quirk selection
instead.  A simple string seems like an easy to implement and use
debug command line option, that has uses outside of kexec.  AKA testing
to see if quirks do what you expect them too.


Which brings us to the question of quirks.  Why are quirks important?
If they are that suggests something else is wrong.  Maybe that something
else should be fixed.

Why do those boards need the DMI information in the first place?

Eric


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel
  2020-01-21 16:29                       ` ebiederm
@ 2020-01-21 17:24                         ` Andy Shevchenko
  0 siblings, 0 replies; 13+ messages in thread
From: Andy Shevchenko @ 2020-01-21 17:24 UTC (permalink / raw)
  To: Eric W. Biederman
  Cc: Jean Delvare, Dave Young, linux-efi, Ard Biesheuvel,
	Matt Fleming, kexec, Linux Kernel Mailing List, Mika Westerberg

On Tue, Jan 21, 2020 at 10:29:35AM -0600, Eric W. Biederman wrote:
> Jean Delvare <jdelvare@suse.de> writes:
> 
> > On Mon, 20 Jan 2020 23:55:43 +0200, Andy Shevchenko wrote:
> >> On Mon, Jan 20, 2020 at 11:44 PM Jean Delvare <jdelvare@suse.de> wrote:
> >> >
> >> > On Mon, 20 Jan 2020 10:04:04 -0600, Eric W. Biederman wrote:  
> >> > > Second.  I looked at your test results and they don't directly make
> >> > > sense.  dmidecode bypasses the kernel completely or it did last time
> >> > > I looked so I don't know why you would be using that to test if
> >> > > something in the kernel is working.  
> >> >
> >> > That must have been long ago. A recent version of dmidecode (>= 3.0)
> >> > running on a recent kernel  
> >> > (>= d7f96f97c4031fa4ffdb7801f9aae23e96170a6f, v4.2) will read the DMI  
> >> > data from /sys/firmware/dmi/tables, so it is very much relying on the
> >> > kernel doing the right thing. If not, it will still try to fallback to
> >> > reading from /dev/mem directly on certain architectures. You can force
> >> > that old method with --no-sysfs.
> >> >
> >> > Hope that helps,  
> >> 
> >> I don't understand how it possible can help for in-kernel code, like
> >> DMI quirks in a drivers.
> >
> > OK, just ignore me then, probably I misunderstood the point made by
> > Eric.
> 
> No.  I just haven't dived into this area of code in a long time.
> 
> It seems a little indirect to use dmidecode as the test to see if the
> kernel has the pointer to the dmitables, but with the knowledge you
> provided it seems like a perfectly valid test.

In any case that doesn't work. See my response to Ard.

-- 
With Best Regards,
Andy Shevchenko



^ permalink raw reply	[flat|nested] 13+ messages in thread

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Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
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2016-12-17 10:57           ` [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel Dave Young
2019-09-06 19:00             ` Andy Shevchenko
2020-01-20 12:19             ` Andy Shevchenko
2020-01-20 16:04               ` ebiederm
2020-01-20 21:42                 ` Jean Delvare
2020-01-20 21:55                   ` Andy Shevchenko
2020-01-21  9:03                     ` Jean Delvare
2020-01-21 16:29                       ` ebiederm
2020-01-21 17:24                         ` Andy Shevchenko
2020-01-20 22:31                 ` Andy Shevchenko
2020-01-20 23:18                   ` Ard Biesheuvel
2020-01-21 15:37                     ` Andy Shevchenko
2020-01-21 17:17                       ` ebiederm

Linux-EFI Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-efi/0 linux-efi/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-efi linux-efi/ https://lore.kernel.org/linux-efi \
		linux-efi@vger.kernel.org
	public-inbox-index linux-efi

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-efi


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git