On Fri, Mar 7, 2014, at 16:52, Steven Rostedt wrote: > > Commit 028a690a1ebc8b "i386: Remove unneeded test of 'task' in dump_trace()" > correctly removed the unneeded 'task != NULL' check because it would > be set to current if it was NULL. > > Commit 2bc5f927d489 "i386: split out dumpstack code from traps_32.c" > moved the code from traps_32.c to its own file dump_stack.c for > preparation of the i386 / x86_64 merge. > > Commit 8a541665b906 "dumpstack: x86: various small unification steps" > worked to make i386 and x86_64 dump_stack logic similar. But this > actually reverted the correct change from 028a690a1ebc8b. > > Commit d0caf292505d "x86/dumpstack: Remove unneeded check in dump_trace()" > removed the unneeded "task != NULL" check for x86_64 but left that same > unneeded check for i386, that was added because x86_64 had it! > > This chain of events ironically had i386 add back the unneeded task != NULL > check because x86_64 did it, and then the fix for x86_64 was fixed > by Dan. And even more ironically, it was Dan's smatch bot that told > me that a change to dump_stack_32 I made may be wrong if current can > be NULL (it can't), as there was a check for it by assigning task to > current, and then checking if task is NULL. > > Reported-by: Dan Carpenter <dan.carpen...@oracle.com> > Cc: Jesper Juhl <jesper.j...@gmail.com> > Cc: Alexander van Heukelum <heuke...@fastmail.fm>
Great archeology ;) Acked-by: Alexander van Heukelum <heuke...@fastmail.fm> > Signed-off-by: Steven Rostedt <rost...@goodmis.org> > --- > arch/x86/kernel/dumpstack_32.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c > index dca820b..5abd4cd 100644 > --- a/arch/x86/kernel/dumpstack_32.c > +++ b/arch/x86/kernel/dumpstack_32.c > @@ -53,7 +53,7 @@ void dump_trace(struct task_struct *task, struct pt_regs > *regs, > unsigned long dummy; > > stack = &dummy; > - if (task && task != current) > + if (task != current) > stack = (unsigned long *)task->thread.sp; > } > > -- > 1.8.1.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
