or to the BSD style persistent flag. I think Shi Weihua's patches have a similar effect by tracking the SP used in the last handler setup. I think it would be sensible for the signal handler setup code to detect when it would itself be causing a stack overflow. Maybe something like the following patch (untested). This issue exists in the same way on all machines, so ideally they would all do a similar check. When it's the handler function itself or its callees that cause the overflow, rather than the signal handler frame setup alone crossing the boundary, this still won't help. But I don't see any way to distinguish that from the valid longjmp case. Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner ĝ