Messages in this thread | | | Date | Mon, 1 Dec 2008 23:40:18 +0100 (CET) | From | Jan Engelhardt <> | Subject | sg_set_page not usable for .bss? |
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On Monday 2008-12-01 23:02, John Haxby wrote: >>>+ sg_init_table(sg, 2); >>>+ sg_set_buf(&sg[0], data, n); >>>+ strcpy(digest_password, sysrq_password); >>>+ i = strlen(digest_password); >>>+ sg_set_buf(&sg[1], digest_password, i); >> >> Could we directly use sysrq_password instead of copying it to >> digest_password first? > > No :-) Eventually I discovered the reason my code wasn't working > boils down to the definition of sg_set_buf: > > sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf)) > > which doesn't work for sysrq_password. I don't know why I'll > double check.
Well, sysrq_password is in the .bss section, where as digest_password is on the heap due to being kmalloc'ed. Maybe that makes a difference? Someone more versed with the virtual memory layer might know.
>+static char sysrq_password[64]; >[...] >+ digest_password = kmalloc(sizeof(sysrq_password), GFP_KERNEL);
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