[flashrom] Re: How to obtain a BIOS image from another computer use flashrom？

[Mike Banon]

Hi there Angel, thank you for your reply and clarification! Please
tell, is this command
> sudo flashrom -p internal:laptop=force_I_want_a_brick,amd_imc_force=yes -r ./build/coreflop.rom

- dangerous to run, even if it's only trying to read (-r) and not
write? (aside from "irritating the EC" possibly causing a sudden
power-off). As for "amd_imc_force=yes", sorry was my mistake

On Mon, Jan 24, 2022 at 3:28 PM Angel Pons  wrote:
> Hi,
>
> On Sun, Jan 23, 2022 at 9:49 AM Mike Banon  wrote:
> > Good day! The flashrom software has the "internal" mode - using which,
> > you may be able to access the BIOS chip directly from your OS, if your
> > hardware is supported. In example:
> >
> > sudo flashrom -p
> > internal:laptop=force_I_want_a_brick,amd_imc_force=yes -r
> > ./build/coreflop.rom
>
> Mike, can you please explain why you've suggested using such a
> dangerous command without even knowing which system it's going to be
> run on? The `force_I_want_a_brick` name is intentional, as flashrom
> can cause problems on certain laptops (most laptops from the last
> decade should be fine, though), c.f. https://www.flashrom.org/Laptops
> for a detailed explanation. And you've suggested using `amd_imc_force`
> even though it only applies to AMD southbridges using SPI.
>
> I know you're just trying to help, but I'm afraid that suggesting
> people to run dangerous commands on unknown hardware without
> mentioning the risks is not helpful.
> > I think this mode is available only on Linux (may have to boot with
> > "iomem=relaxed" kernel flag) - however, you may boot a Linux LiveUSB
> > on your target PC to use Linux without the installation in a live
> > mode.
>
> On x86, the internal programmer should also work on most BSDs and
> Darwin (macOS). It might even work on Solaris.
>
> On Linux, the `iomem=relaxed` kernel parameter can be used when a
> kernel module conflicts with the resources flashrom wants to use, but
> it reduces the system's security. On Intel systems, unloading the
> `lpc_ich` kernel module should allow using flashrom's internal
> programmer without having to boot with `iomem=relaxed`.
> > As for "how do I remotely obtain a BIOS image from another computer
> > using flashrom" - if this internal mode is available to you, and a
> > target PC is running Linux, you can remotely connect to this PC using
> > a SSH (or VPN + SSH), run the flashrom command to read a BIOS image
> > from a chip, and then - using scp - copy the obtained BIOS image to
> > your own PC
> >
> > On Fri, Jan 21, 2022 at 3:26 AM zy  wrote:
> > > Hi，
> > >    I'm a student from China and I've been learning flashrom，So I would like to know whether the flashrom can support extracting BIOS firmware images under Windows 7/10.
> > >    If I don't have the Internet（Just LAN），how do I remotely obtain a BIOS image from another computer use flashrom？
> > >    Maybe my English not very well. Thank you very much.
>
> On Windows, flashrom's internal programmer is unusable. It requires
> libpci and raw memory access; libpci is not available on Windows as
> far as I know, and I think Windows restricts raw memory access from
> userspace code for security reasons. One could try to implement the
> required functionality in a driver, but one would also need to
> convince Microsoft to sign the driver. It could be done, but it's not
> easy. No one is working on this, as far as I know.
> > > Looking forward to your reply.
> > >
> > > flashrom mailing list -- [e-mail]
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>
> Best regards,
> Angel