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 <m.b.lankhorst@gmail.com>
Link: http://lkml.kernel.org/r/4EEB3A02.3090201@gmail.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 4055e63..fec216f 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -643,14 +643,22 @@
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 f66d023..3925166 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