On Sat, Sep 19, 2020 at 09:55:46AM +0800, Youling Tang wrote: > When the kernel crashkernel parameter is specified with just a size, > we are supposed to allocate a region from RAM to store the crashkernel. > However, MIPS merely reserves physical address zero with no checking > that there is even RAM there. > > Fix this by lifting similar code from x86, importing it to MIPS with the > MIPS specific parameters added. In the absence of any platform specific > information, we allocate the crashkernel region from the first 512MB of > physical memory (limited to CKSEG0 or KSEG0 address range). > > When X is not specified, crash_base defaults to 0 (crashkernel=YM@XM). > > E.g. without this patch: > > The environment as follows: > [ 0.000000] MIPS: machine is loongson,loongson64c-4core-ls7a > ... > [ 0.000000] Kernel command line: root=/dev/sda2 crashkernel=96M ... > > The warning as follows: > [ 0.000000] Invalid memory region reserved for crash kernel > > And the iomem as follows: > 00200000-0effffff : System RAM > 00200000-00b47f87 : Kernel code > 00b47f88-00dfffff : Kernel data > 00e60000-01f73c7f : Kernel bss > 1a000000-1bffffff : pci@1a000000 > ... > > With this patch: > > After increasing crash_base <= 0 handling. > > And the iomem as follows: > 00200000-0effffff : System RAM > 00200000-00b47f87 : Kernel code > 00b47f88-00dfffff : Kernel data > 00e60000-01f73c7f : Kernel bss > 04000000-09ffffff : Crash kernel > 1a000000-1bffffff : pci@1a000000 > ... > > Signed-off-by: Youling Tang <tangyouling@xxxxxxxxxxx> > --- > arch/mips/kernel/setup.c | 24 +++++++++++++++++++++--- > 1 file changed, 21 insertions(+), 3 deletions(-) applied to mips-next. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]
