Re: [PATCH v4 0/4] MIPS: Modify mem= and memmap= parameter

[Tiezhu Yang]

On 03/01/2022 05:55 PM, Mike Rapoport wrote:
> Hi,
>
> On Tue, Mar 01, 2022 at 12:28:57PM +0800, Tiezhu Yang wrote:
> > In the current code, the kernel command-line parameter mem= and memmap=
> > can not work well on MIPS, this patchset refactors the related code to
> > fix them.
> >
> > For kdump on MIPS, if the users want to limit the memory region for the
> > capture kernel to avoid corrupting the memory image of the panic kernel,
> > use the parameter memmap=limit@base is the proper way, I will submit a
> > patch to use memmap=limit@base for kexec-tools after this patchset is
> > applied.
>
> Sorry, apparently I misread the prevoius version.
> What's wrong with the current implementation of mem=limit@base for the
> kdump case?

In the current code, without this patchset, kernel boot hangs when add
mem=3G, mem=3G@64M or memmap=3G@64M to the command-line, it means that
the parameter mem= and memmap= have bug on mips.

Thanks,
Tiezhu

> > v4: Fix some build warnings reported by kernel test robot
> >
> > v3: Modify patch #3 to maintain compatibility for memmap=limit{$,#,!}base,
> >     commented by Mike Rapoport, thank you
> >
> > v2: Add some new patches to support memmap=limit@base
> >
> > Tiezhu Yang (4):
> >   MIPS: Refactor early_parse_mem() to fix mem= parameter
> >   memblock: Introduce memblock_mem_range_remove_map()
> >   MIPS: Refactor early_parse_memmap() to fix memmap= parameter
> >   MIPS: Remove not used variable usermem
> >
> >  arch/mips/kernel/setup.c | 69 ++++++++++++++++++++++--------------------------
> >  include/linux/memblock.h |  1 +
> >  mm/memblock.c            |  9 +++++--
> >  3 files changed, 40 insertions(+), 39 deletions(-)
> >
> > --
> > 2.1.0