From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH 2/3] powerpc: kdump: CPUs assume the context of the oopsing CPU From: Michael Ellerman To: Anton Blanchard In-Reply-To: <20100511022551.GF12203@kryten> References: <20100511022329.GE12203@kryten> <20100511022551.GF12203@kryten> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-1QL28XRoePewfZQR9dq4" Date: Tue, 11 May 2010 14:14:31 +1000 Message-ID: <1273551271.9209.135.camel@concordia> Mime-Version: 1.0 Cc: mikey@neuling.org, paulus@samba.org, miltonm@bga.com, linuxppc-dev@ozlabs.org Reply-To: michael@ellerman.id.au List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --=-1QL28XRoePewfZQR9dq4 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2010-05-11 at 12:25 +1000, Anton Blanchard wrote: > We wrap the crash_shutdown_handles[] calls with longjmp/setjmp, so if any > of them fault we can recover. The problem is we add a hook to the debugge= r > fault handler hook which calls longjmp unconditionally. >=20 > This first part of kdump is run before we marshall the other CPUs, so the= re > is a very good chance some CPU on the box is going to page fault. And whe= n > it does it hits the longjmp code and assumes the context of the oopsing C= PU. > The machine gets very confused when it has 10 CPUs all with the same stac= k, > all thinking they have the same CPU id. I get even more confused trying > to debug it. Lol, guess that one didn't get tested that well :) Fix looks good. cheers --=-1QL28XRoePewfZQR9dq4 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEABECAAYFAkvo2acACgkQdSjSd0sB4dLJ1gCdGpeqbMbx9wk9H4UxTzIRitms 9pwAn1M4XoiwjuXOM+iUskoHjW0XRwuu =OU02 -----END PGP SIGNATURE----- --=-1QL28XRoePewfZQR9dq4--