On 11/04/2024 4:25 pm, Daniel P. Smith wrote:
> diff --git a/xen/common/gzip/inflate.c b/xen/common/gzip/inflate.c
> index c8dd35962abb..6c8c7452a31f 100644
> --- a/xen/common/gzip/inflate.c
> +++ b/xen/common/gzip/inflate.c
> @@ -1125,16 +1125,14 @@ static int __init inflate(struct gzip_data *gd)
> *
> **********************************************************************/
>
> -static ulg __initdata crc_32_tab[256];
> -static ulg __initdata crc; /* initialized in makecrc() so it'll reside in
> bss */
> -#define CRC_VALUE (crc ^ 0xffffffffUL)
> +#define CRC_VALUE (gd->crc ^ 0xffffffffUL)
>
> /*
> * Code to compute the CRC-32 table. Borrowed from
> * gzip-1.0.3/makecrc.c.
> */
>
> -static void __init makecrc(void)
> +static void __init makecrc(struct gzip_data *gd)
> {
> /* Not copyrighted 1990 Mark Adler */
>
> @@ -1151,7 +1149,7 @@ static void __init makecrc(void)
> for (i = 0; i < sizeof(p)/sizeof(int); i++)
> e |= 1L << (31 - p[i]);
>
> - crc_32_tab[0] = 0;
> + gd->crc_32_tab[0] = 0;
>
> for (i = 1; i < 256; i++)
> {
> @@ -1162,11 +1160,11 @@ static void __init makecrc(void)
> if (k & 1)
> c ^= e;
> }
> - crc_32_tab[i] = c;
> + gd->crc_32_tab[i] = c;
> }
>
> /* this is initialized here so this code could reside in ROM */
> - crc = (ulg)0xffffffffUL; /* shift register contents */
> + gd->crc = (ulg)0xffffffffUL; /* shift register contents */
> }
>
> /* gzip flag byte */
I can't see any way that a non-32bit value ever gets stored, because 'e'
doesn't ever have bit 32 set in it. I have a sneaking suspicion that
this is code written in the 32bit days, where sizeof(long) was still 4.
This change, if correct, halves the size of gzip_state.
~Andrew
