From 4b9c15377f96e241be347fd3bbeeff74fbad0b44 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Fri, 17 Jul 2015 06:51:32 +0200 Subject: [PATCH] xen: check for initrd conflicting with e820 map Check whether the initrd is placed at a location which is conflicting with the target E820 map. If this is the case relocate it to a new area unused up to now and compliant to the E820 map. Signed-off-by: Juergen Gross Reviewed-by: David Vrabel Acked-by: Konrad Rzeszutek Wilk Signed-off-by: David Vrabel --- arch/x86/xen/setup.c | 51 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 3fca9c114828..0d7f8818f8ca 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -631,6 +631,36 @@ phys_addr_t __init xen_find_free_area(phys_addr_t size) return 0; } +/* + * Like memcpy, but with physical addresses for dest and src. + */ +static void __init xen_phys_memcpy(phys_addr_t dest, phys_addr_t src, + phys_addr_t n) +{ + phys_addr_t dest_off, src_off, dest_len, src_len, len; + void *from, *to; + + while (n) { + dest_off = dest & ~PAGE_MASK; + src_off = src & ~PAGE_MASK; + dest_len = n; + if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off) + dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off; + src_len = n; + if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off) + src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off; + len = min(dest_len, src_len); + to = early_memremap(dest - dest_off, dest_len + dest_off); + from = early_memremap(src - src_off, src_len + src_off); + memcpy(to, from, len); + early_memunmap(to, dest_len + dest_off); + early_memunmap(from, src_len + src_off); + n -= len; + dest += len; + src += len; + } +} + /* * Reserve Xen mfn_list. * See comment above "struct start_info" in @@ -810,6 +840,27 @@ char * __init xen_memory_setup(void) xen_reserve_xen_mfnlist(); + /* Check for a conflict of the initrd with the target E820 map. */ + if (xen_is_e820_reserved(boot_params.hdr.ramdisk_image, + boot_params.hdr.ramdisk_size)) { + phys_addr_t new_area, start, size; + + new_area = xen_find_free_area(boot_params.hdr.ramdisk_size); + if (!new_area) { + xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n"); + BUG(); + } + + start = boot_params.hdr.ramdisk_image; + size = boot_params.hdr.ramdisk_size; + xen_phys_memcpy(new_area, start, size); + pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n", + start, start + size, new_area, new_area + size); + memblock_free(start, size); + boot_params.hdr.ramdisk_image = new_area; + boot_params.ext_ramdisk_image = new_area >> 32; + } + /* * Set identity map on non-RAM pages and prepare remapping the * underlying RAM. -- 2.34.1