On Mon, 27 Oct 2008 14:39:32 +0100 (CET), Geert Uytterhoeven <Geert.Uytterhoeven@xxxxxxxxxxx> wrote: > > BTW, it looks fw_arg0 is not 'argc'. Fortunately current code just > > ignores argv if argc was negative, but it is not intentional > > behaviour, just a luck ;) > > Woops... > > The memory pointed to by fw_arg0 and fw_arg1 contains just zeroes. > > According to the sources, the VxWorks bootloader just jumps to the kernel's > entry point, without passing any parameters in a0-a3 at all. So they're just > leftovers. Wow, what a simple loader ... > > You can put a string starting with "-" in CONFIG_CMDLINE, so that > > fw_arg0 is ignored regardless of its value. Hmm... putting "noenv" or > > something in CONFIG_CMDLINE (and check it in preprocess_cmdline()) can > > be an another workaround for getenv problem... > > Prepending my command line in CONFIG_CMDLINE with `-' doesn't help. > prom_getenv() is still called. > > So I came up with the patch below. Oh, yes, the '-' does not prevent prom_getenv(). It just prevents argc/argv parsing. Anyway, checking invalid fw_argN should be good. > Subject: [PATCH] txx9: Make firmware parameter passing more robust > > When booting Linux on a txx9 board with VxWorks boot loader, it crashes in > prom_getenv(), as VxWorks doesn't pass firmware parameters in a0-a3 (in my > case, the actual leftover values in these registers were 0x80002000, > 0x80001fe0, 0x2000, and 0x20). > > Make the parsing of argc, argv, and envp a bit more robust by checking if argc > is a number below CKSEG0, and argv/envp point to CKSEG0. > > Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@xxxxxxxxxxx> Look OK for me, except for coding style :) If TAB was used for indent, Acked-by: Atsushi Nemoto <anemo@xxxxxxxxxxxxx>
