From 2d2da60fb40a80cc59383121ccf763e0e0e8a42a Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Fri, 16 Dec 2011 13:30:58 +0100 Subject: [PATCH] x86, efi: Break up large initrd reads The efi boot stub tries to read the entire initrd in 1 go, however some efi implementations hang if too much if asked to read too much data at the same time. After some experimentation I found out that my asrock p67 board will hang if asked to read chunks of 4MiB, so use a safe value. elilo reads in chunks of 16KiB, but since that requires many read calls I use a value of 1 MiB. hpa suggested adding individual blacklists for when systems are found where this value causes a crash. Signed-off-by: Maarten Lankhorst Link: http://lkml.kernel.org/r/4EEB3A02.3090201@gmail.com Signed-off-by: H. Peter Anvin --- arch/x86/boot/compressed/eboot.c | 20 ++++++++++++++------ arch/x86/boot/compressed/eboot.h | 1 + 2 files changed, 15 insertions(+), 6 deletions(-) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 4055e63d0b04..fec216f4fbc3 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -643,14 +643,22 @@ static efi_status_t handle_ramdisks(efi_loaded_image_t *image, u64 size; size = initrds[j].size; - status = efi_call_phys3(fh->read, initrds[j].handle, - &size, addr); - if (status != EFI_SUCCESS) - goto free_initrd_total; + while (size) { + u64 chunksize; + if (size > EFI_READ_CHUNK_SIZE) + chunksize = EFI_READ_CHUNK_SIZE; + else + chunksize = size; + status = efi_call_phys3(fh->read, + initrds[j].handle, + &chunksize, addr); + if (status != EFI_SUCCESS) + goto free_initrd_total; + addr += chunksize; + size -= chunksize; + } efi_call_phys1(fh->close, initrds[j].handle); - - addr += size; } } diff --git a/arch/x86/boot/compressed/eboot.h b/arch/x86/boot/compressed/eboot.h index f66d023e91ef..39251663e65b 100644 --- a/arch/x86/boot/compressed/eboot.h +++ b/arch/x86/boot/compressed/eboot.h @@ -12,6 +12,7 @@ #define DESC_TYPE_CODE_DATA (1 << 0) #define EFI_PAGE_SIZE (1UL << EFI_PAGE_SHIFT) +#define EFI_READ_CHUNK_SIZE (1024 * 1024) #define PIXEL_RGB_RESERVED_8BIT_PER_COLOR 0 #define PIXEL_BGR_RESERVED_8BIT_PER_COLOR 1 -- GitLab