From 0ec7ec75f674dbf48010081383263771f2611e72 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Thu, 15 Nov 2012 12:53:59 +0100 Subject: [PATCH] MIPS: Merge overlapping bootmem ranges Without this, we may end up with something like this in /proc/iomem: 01100000-014fffff : System RAM 01100000-013bf48f : Kernel code 013bf490-0149e01f : Kernel data 01500000-0c0fffff : System RAM but the two System RAM ranges should be one single range. This particular case will result in kexec failure on Octeon systems if the kernel being loaded by kexec is bigger than the already running kernel. Signed-off-by: Ralf Baechle --- arch/mips/kernel/setup.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index a53f8ec37aac..290dc6a1d7a3 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -79,7 +79,7 @@ static struct resource data_resource = { .name = "Kernel data", }; void __init add_memory_region(phys_t start, phys_t size, long type) { int x = boot_mem_map.nr_map; - struct boot_mem_map_entry *prev = boot_mem_map.map + x - 1; + int i; /* Sanity check */ if (start + size < start) { @@ -88,15 +88,29 @@ void __init add_memory_region(phys_t start, phys_t size, long type) } /* - * Try to merge with previous entry if any. This is far less than - * perfect but is sufficient for most real world cases. + * Try to merge with existing entry, if any. */ - if (x && prev->addr + prev->size == start && prev->type == type) { - prev->size += size; + for (i = 0; i < boot_mem_map.nr_map; i++) { + struct boot_mem_map_entry *entry = boot_mem_map.map + i; + unsigned long top; + + if (entry->type != type) + continue; + + if (start + size < entry->addr) + continue; /* no overlap */ + + if (entry->addr + entry->size < start) + continue; /* no overlap */ + + top = max(entry->addr + entry->size, start + size); + entry->addr = min(entry->addr, start); + entry->size = top - entry->addr; + return; } - if (x == BOOT_MEM_MAP_MAX) { + if (boot_mem_map.nr_map == BOOT_MEM_MAP_MAX) { pr_err("Ooops! Too many entries in the memory map!\n"); return; }