On Wed, Sep 19, 2018 at 3:52 PM, Christophe LEROY
<christophe.le...@c-s.fr> wrote:
>
>
> Le 19/09/2018 à 01:07, Joel Stanley a écrit :
>>
>> This partially reverts faa16bc404d72a5 ("lib: Use existing define with
>> polynomial").
>>
>> The cleanup added a dependency on include/linux, which broke the PowerPC
>> boot wrapper/decompresser when KERNEL_XZ is enabled:
>>
>> BOOTCC arch/powerpc/boot/decompress.o
>> In file included from
>> arch/powerpc/boot/../../../lib/decompress_unxz.c:233,
>> from arch/powerpc/boot/decompress.c:42:
>> arch/powerpc/boot/../../../lib/xz/xz_crc32.c:18:10: fatal error:
>> linux/crc32poly.h: No such file or directory
>> #include <linux/crc32poly.h>
>> ^~~~~~~~~~~~~~~~~~~
>>
>> The powerpc decompressor is a hairy corner of the kernel. Even while
>> building
>> a 64-bit kernel it needs to build a 32-bit binary and therefore avoid
>> including
>> files from include/linux.
>>
>> Fixes: faa16bc404d7 ("lib: Use existing define with polynomial")
>> Signed-off-by: Joel Stanley <j...@jms.id.au>
>> ---
>> We need to clean up the powerpc boot decompresser but that work will be
>> more involved than we would include in a late -rc. Please consider
>> merging this fix for 4.19. Thanks!
>>
>> lib/xz/xz_crc32.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/lib/xz/xz_crc32.c b/lib/xz/xz_crc32.c
>> index 25a5d87e2e4c..34532d14fd4c 100644
>> --- a/lib/xz/xz_crc32.c
>> +++ b/lib/xz/xz_crc32.c
>> @@ -15,7 +15,6 @@
>> * but they are bigger and use more memory for the lookup table.
>> */
>> -#include <linux/crc32poly.h>
>> #include "xz_private.h"
>> /*
>> @@ -30,7 +29,7 @@ STATIC_RW_DATA uint32_t xz_crc32_table[256];
>> XZ_EXTERN void xz_crc32_init(void)
>> {
>> - const uint32_t poly = CRC32_POLY_LE;
>> + const uint32_t poly = 0xEDB88320;
>
>
> Maybe avoid capital letters ?
>
> What about adding something like the following in xz_private.h instead:
>
> #define CRC32_POLY_LE 0xedb88320
The problem is that it's pulling in linux/crc32poly.h. To support old
systems with a 32bit Open Firmware we boot wrapper we build the boot
wrapper as a 32bit ELF even for a 64 bit kernel. The headers generated
by Kbuild are only valid for the 64bit kernel so we have to avoid
pulling them into the boot wrapper.
> Christophe
>
>> uint32_t i;
>> uint32_t j;
>>
>
