@@ -361,7 +361,6 @@ early_param("mem", early_parse_mem);
static int __init early_parse_memmap(char *p)
{
char *oldp;
- u64 start_at, mem_size;
if (!p)
return -EINVAL;
@@ -372,30 +371,38 @@ static int __init early_parse_memmap(char *p)
}
oldp = p;
- mem_size = memparse(p, &p);
+ memory_limit = memparse(p, &p) & PAGE_MASK;
if (p == oldp)
return -EINVAL;
if (*p == '@') {
- start_at = memparse(p+1, &p);
- memblock_add(start_at, mem_size);
+ memory_base = memparse(p + 1, &p) & PAGE_MASK;
+ } else if (*p == '$') {
+ memory_base = memparse(p+1, &p) & PAGE_MASK;
+ memblock_reserve(memory_base, memory_limit);
+ pr_notice("Memory reserved to %lluMB-%lluMB\n",
+ (u64)memory_base >> 20, (u64)(memory_base + memory_limit) >> 20);
+ memory_base = 0;
+ memory_limit = 0;
+ return 0;
} else if (*p == '#') {
- pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
+ pr_err("\"memmap=nn#ss\" invalid on MIPS\n");
+ memory_limit = 0;
+ return -EINVAL;
+ } else if (*p == '!') {
+ pr_err("\"memmap=nn!ss\" invalid on MIPS\n");
+ memory_limit = 0;
return -EINVAL;
- } else if (*p == '$') {
- start_at = memparse(p+1, &p);
- memblock_add(start_at, mem_size);
- memblock_reserve(start_at, mem_size);
} else {
- pr_err("\"memmap\" invalid format!\n");
+ pr_err("Unrecognized memmap syntax: %s\n", p);
+ memory_limit = 0;
return -EINVAL;
}
- if (*p == '\0') {
- usermem = 1;
- return 0;
- } else
- return -EINVAL;
+ pr_notice("Memory limited to %lluMB-%lluMB\n",
+ (u64)memory_base >> 20, (u64)(memory_base + memory_limit) >> 20);
+
+ return *p == '\0' ? 0 : -EINVAL;
}
early_param("memmap", early_parse_memmap);
According to Documentation/admin-guide/kernel-parameters.txt, the kernel command-line parameter memmap= means "Force usage of a specific region of memory", but when add "memmap=3G@64M" to the command-line, kernel boot hangs in sparse_init(). In order to support memmap=limit@base, refactor the function early_parse_memmap() to limit the memory region. With this patch, when add "memmap=3G@64M" to the command-line, the kernel boots successfully, we can see the following messages: [ 0.000000] Memory limited to 64MB-3136MB ... [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000004000000-0x000000000effffff] [ 0.000000] node 0: [mem 0x0000000090200000-0x00000000ffffffff] [ 0.000000] node 0: [mem 0x0000000120000000-0x00000001653fffff] ... [ 0.000000] Memory: 3070816K/3147776K available (...) After login, the output of free command is consistent with the above log. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> --- arch/mips/kernel/setup.c | 37 ++++++++++++++++++++++--------------- 1 file changed, 22 insertions(+), 15 deletions(-)