From d9d814eebb1ae9742e7fd7f39730653b16326bd4 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Thu, 13 Jun 2024 11:55:08 -0400 Subject: pstore/ramoops: Add ramoops.mem_name= command line option Add a method to find a region specified by reserve_mem=nn:align:name for ramoops. Adding a kernel command line parameter: reserve_mem=12M:4096:oops ramoops.mem_name=oops Will use the size and location defined by the memmap parameter where it finds the memory and labels it "oops". The "oops" in the ramoops option is used to search for it. This allows for arbitrary RAM to be used for ramoops if it is known that the memory is not cleared on kernel crashes or soft reboots. Tested-by: Guilherme G. Piccoli Signed-off-by: Steven Rostedt (Google) Acked-by: Kees Cook Link: https://lore.kernel.org/r/20240613155527.591647061@goodmis.org Signed-off-by: Mike Rapoport (IBM) --- fs/pstore/ram.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'fs') diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index b1a455f42e93..4311fcbc84f2 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -50,6 +50,10 @@ module_param_hw(mem_address, ullong, other, 0400); MODULE_PARM_DESC(mem_address, "start of reserved RAM used to store oops/panic logs"); +static char *mem_name; +module_param_named(mem_name, mem_name, charp, 0400); +MODULE_PARM_DESC(mem_name, "name of kernel param that holds addr"); + static ulong mem_size; module_param(mem_size, ulong, 0400); MODULE_PARM_DESC(mem_size, @@ -914,6 +918,16 @@ static void __init ramoops_register_dummy(void) { struct ramoops_platform_data pdata; + if (mem_name) { + phys_addr_t start; + phys_addr_t size; + + if (reserve_mem_find_by_name(mem_name, &start, &size)) { + mem_address = start; + mem_size = size; + } + } + /* * Prepare a dummy platform data structure to carry the module * parameters. If mem_size isn't set, then there are no module -- cgit