From: Hari Bathini <hbathini@xxxxxxxxxxxxxxxxxx> Subject: powerpc/fadump: update documentation about crashkernel parameter reuse As we are reusing crashkernel parameter instead of fadump_reserve_mem parameter to specify the memory to reserve for fadump's crash kernel, update the documentation accordingly. Link: http://lkml.kernel.org/r/149035347559.6881.14224829694291758581.stgit@xxxxxxxxxxxxxxxxxxx Signed-off-by: Hari Bathini <hbathini@xxxxxxxxxxxxxxxxxx> Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Dave Young <dyoung@xxxxxxxxxx> Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx> Cc: Mahesh Salgaonkar <mahesh@xxxxxxxxxxxxxxxxxx> Cc: Vivek Goyal <vgoyal@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/powerpc/firmware-assisted-dump.txt | 23 ++++++++----- 1 file changed, 15 insertions(+), 8 deletions(-) diff -puN Documentation/powerpc/firmware-assisted-dump.txt~powerpc-fadump-update-documentation-about-crashkernel-parameter-reuse Documentation/powerpc/firmware-assisted-dump.txt --- a/Documentation/powerpc/firmware-assisted-dump.txt~powerpc-fadump-update-documentation-about-crashkernel-parameter-reuse +++ a/Documentation/powerpc/firmware-assisted-dump.txt @@ -55,10 +55,14 @@ as follows: booted with restricted memory. By default, the boot memory size will be the larger of 5% of system RAM or 256MB. Alternatively, user can also specify boot memory size - through boot parameter 'fadump_reserve_mem=' which will - override the default calculated size. Use this option - if default boot memory size is not sufficient for second - kernel to boot successfully. + through boot parameter 'crashkernel=' which will override + the default calculated size. Use this option if default + boot memory size is not sufficient for second kernel to + boot successfully. For syntax of crashkernel= parameter, + refer to Documentation/kdump/kdump.txt. If any offset is + provided in crashkernel= parameter, it will be ignored + as fadump reserves memory at end of RAM for boot memory + dump preservation in case of a crash. -- After the low memory (boot memory) area has been saved, the firmware will reset PCI and other hardware state. It will @@ -158,13 +162,16 @@ How to enable firmware-assisted dump (fa 1. Set config option CONFIG_FA_DUMP=y and build kernel. 2. Boot into linux kernel with 'fadump=on' kernel cmdline option. -3. Optionally, user can also set 'fadump_reserve_mem=' kernel cmdline +3. Optionally, user can also set 'crashkernel=' kernel cmdline to specify size of the memory to reserve for boot memory dump preservation. -NOTE: If firmware-assisted dump fails to reserve memory then it will - fallback to existing kdump mechanism if 'crashkernel=' option - is set at kernel cmdline. +NOTE: 1. 'fadump_reserve_mem=' parameter has been deprecated. Instead + use 'crashkernel=' to specify size of the memory to reserve + for boot memory dump preservation. + 2. If firmware-assisted dump fails to reserve memory then it + will fallback to existing kdump mechanism if 'crashkernel=' + option is set at kernel cmdline. Sysfs/debugfs files: ------------ _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
