Re: [PATCH -v5 6/5] context_tracking: fix exception_enter when already in IN_KERNEL

[Rik van Riel]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 02/12/2015 10:42 AM, Frederic Weisbecker wrote:
> On Wed, Feb 11, 2015 at 02:43:19PM -0500, Rik van Riel wrote:
>> If exception_enter happens when already in IN_KERNEL state, the 
>> code still calls context_tracking_exit, which ends up in 
>> rcu_eqs_exit_common, which explodes with a WARN_ON when it is 
>> called in a situation where dynticks are not enabled.
> 
> Fortunately context_tracking_exit() already has a current_state ==
> IN_KERNEL check so this shouldn't be a problem.

No, it had a hard-coded "current_state == IN_USER" check,
which is very close, but ...

... I replaced that with a state argument, and forgot to
ensure that it never gets called with state == IN_KERNEL.
This patch fixes that.

> Meanwhile I'll still take the patch, it's better to handle that 
> from the caller.

Thanks.

- -- 
All rights reversed
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1

iQEcBAEBAgAGBQJU3Mr+AAoJEM553pKExN6DYNUH/2m9CtXhLdTHOEHRvxg41PCZ
/xafetUOS9cka0CNuiYpUuvfMSucoePW7YqUXqjYSIP25DsAleOh0qdep1Ob5bH+
2BqZNMwK3QDHf1+/V7nulnjVkeHtpXJm0HIZOjc06xeL+9T6ydB1vhQGIMLrGL9S
LvOstI3fseeIgglwYc2Gx7H7e99oOkxysvwMMvcMrW0cPSRAOdYxINQnfYW8A5kq
DTTXwWuJRZa4FLtP3wLpvocm5dMGDwTsDmuOk1PmXYlsTsO6H2BmCeio0euzStoJ
l+jR4x7Aq2KXES7gnMgpPw1iON3xKJ/RbXF8IC/doII8FYEV8Raxnf7hl47etBw=
=yIjW
-----END PGP SIGNATURE-----
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/