Re: [Madwifi-devel] PATCH: fix kernel panic on sysctl dev.ath.txpowlimit

[Christian V. <ch...@ob...>]

Hi Mike,

On Thu, Jun 02, 2005 at 09:16:04PM +0200, Michael Renzmann wrote:
> Looks reasonable, but maybe we should also check if calling
> ath_sysctl_halparam with a NULL sc is invalid and where that happens.

so I searched a littlemore and found that this is most likely
due to the definition of that sysctl in if_ath.c, line 4775:

        { .ctl_name     = ATH_TXPOWLIMIT,
           .procname     = "txpowlimit",
           .mode         = 0644,
           .proc_handler = ath_sysctl_halparam
        },

here also other sysctls are defined but no .extra1 member is filled
for TXPOWLIMIT.  I naively assume that this will be later stuffed into
ctl->extra1 (which then is NULL). But there are also other
sysctl_halparam sysctls which don't have extra1 defined but sysctl -a
only panics on one, so maybe someone with a better understanding
of that particular driver should have a look at it.

> Else finding the root for this problem (and potentionally others) will
> be harder after the patch has been committed.

well.. not having your machine lock up during bug-searching sure
is an improvement, isn't it :-) ?

	Chris