Re: [PATCH (2.4)] atomic use count for proc_dir_entry

From: Francois romieu (romieu@ensta.fr)
Date: Fri Nov 17 2000 - 06:23:33 EST

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CPU A: assume de->count = 1 (in de_put)
fs/proc/inode.c::44 if (!--de->count) {
de->count = 0

CPU B: (in remove_proc_entry)
fs/proc/generic.c::577 if (!de->count)
fs/proc/generic.c::578 free_proc_entry(de);

CPU A: (in de_put)
fs/proc/inode.c::45 if (de->deleted) { <-- dereferencing kfreed pointer

What does protect us from the preceding if lock_kernel is thrown ?

-- 
Ueimor
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Next message: Tim Waugh: "Re: [PATCH] (new for ppa and imm) Re: [PATCH] Re: Patch to fix lockup on ppa insert"
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