From 0b69943f26ca4e126c46d52a7a94efdd82729511 Mon Sep 17 00:00:00 2001 From: Hongyan Xia Date: Tue, 6 Apr 2021 15:11:53 +0100 Subject: Shrink segments to fit alignment instead of throwing them away We risk throwing an entire large chunk away if it is just slightly unaligned which then causes the crash kernel to run out of RAM. Keep them and shrink them to alignment. Signed-off-by: Hongyan Xia Signed-off-by: Simon Horman --- kexec/arch/i386/crashdump-x86.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'kexec') diff --git a/kexec/arch/i386/crashdump-x86.c b/kexec/arch/i386/crashdump-x86.c index df84185..0dada99 100644 --- a/kexec/arch/i386/crashdump-x86.c +++ b/kexec/arch/i386/crashdump-x86.c @@ -483,9 +483,18 @@ static int add_memmap(struct memory_range *memmap_p, int *nr_memmap, int i, j, nr_entries = 0, tidx = 0, align = 1024; unsigned long long mstart, mend; - /* Do alignment check if it's RANGE_RAM */ - if ((type == RANGE_RAM) && ((addr%align) || (size%align))) - return -1; + /* Shrink to 1KiB alignment if needed. */ + if (type == RANGE_RAM && ((addr%align) || (size%align))) { + unsigned long long end = addr + size; + + printf("%s: RAM chunk %#llx - %#llx unaligned\n", __func__, addr, end); + addr = _ALIGN_UP(addr, align); + end = _ALIGN_DOWN(end, align); + if (addr >= end) + return -1; + size = end - addr; + printf("%s: RAM chunk shrunk to %#llx - %#llx\n", __func__, addr, end); + } /* Make sure at least one entry in list is free. */ for (i = 0; i < CRASH_MAX_MEMMAP_NR; i++) { -- cgit