From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Subject: Re: [PATCH 0/3] PCI: Rework config space locking, add INTx masking services Date: Thu, 6 Oct 2011 08:48:53 -0700 Message-ID: <20111006084853.033d8d0f@jbarnes-desktop> References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/NixJ727_2l_meqealkDUGK3"; protocol="application/pgp-signature" Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, "Hans J. Koch" , Greg Kroah-Hartman , "Michael S. Tsirkin" , kvm@vger.kernel.org, Brian King To: Jan Kiszka Return-path: In-Reply-To: Sender: linux-pci-owner@vger.kernel.org List-Id: kvm.vger.kernel.org --Sig_/NixJ727_2l_meqealkDUGK3 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 12 Sep 2011 18:54:01 +0200 Jan Kiszka wrote: > This series tries to heal the currently broken locking scheme around PCI > config space accesses. >=20 > We have an interface lock out access via sysfs, but that service wrongly > assumes it is only called by one instance at a time for some device. So > two loops doing >=20 > echo 1 > /sys/bus/pci/devices//reset >=20 > in parallel will trigger a kernel BUG at the moment. >=20 > Besides synchronizing with user space, we also need to manage config > space access of generic PCI drivers. They need to mask legacy interrupt > lines while the specific driver runs in user space or a guest OS. >=20 > The approach taken here is provide mutex-like locking for general > access - which still requires a special mechanism due to requirements of > the IBM Power RAID SCSI driver. Furthermore, INTx masking is now > available via the PCI core and synchronized via the internal pci_lock. >=20 > Not sure who may want to take this, so I'm CC'ing broadly. ISTR a bunch of discussion about this (just back from lots of work travel and vacation, sorry I missed most of it). Is this the agreed upon way of handling it? If so, can I get some Reviewed/Acked-bys from people? Thanks, --=20 Jesse Barnes, Intel Open Source Technology Center --Sig_/NixJ727_2l_meqealkDUGK3 Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQIbBAEBAgAGBQJOjc3lAAoJEIEoDkX4Qk9h/24P9R98+ZFNqaAjdZhZ8sHDwo0S Zh8bPLNAssSD9aSW4tXbDZI3aFCNabQOm/+uxi3mk7AdMLs7oLF9hlW5JZoGmvc9 dxKjEj/CI9MDm4rGC0wRknsZr9UnoUUIzErJ23bmhySRc0gox6jYSCignG/YMHAr mnFO3jnwTylnTRdvI5ZxsCxVC/N1F1jnSAK2P7YLazwmwnak8ocb3ZfVLOBFH4F3 8VUaj6uAh1DN6d0hgeiuPM6OGMiIDHrktkM3q23w9086d1D/HYQIj/JeqOK2gVgW CzlDg+X5MII5gssKYmpyGOq+6pTaWxBAO7I1sES0uzSL2TTMLN/slGg162qk6ZzI omylnCkBwi9cTKKVBCWjsU+uAcQJlGfhSEwYH85qaKUkV2EGeaAphbp4X69I7Zpn Ci2J4vNGD20GD61HzseLbja77TdXJAAAuYDvbX8nFZ1QrA8yPkl2r4Mnm0290OCn S8jzvfABBVnox8xlyyyHJUta8Kt48bDUvGFwNFKym0m1+5R2k0xUknbgyTFwsnMh 1ibxrNaLYMGkbOtzvCfsDAm0D5sVk7FHtZDd3IrvB3XxQA9C1eC9DmYppkdiTUda IWRQPQc6bUZMpYUw+NSs0fnHQNMUUWDIHm9IaSxrsurCNrDf7bkk8Vg8Wn1Y0v0O 46/BB5SQI5OR6U9vlMI= =Slmy -----END PGP SIGNATURE----- --Sig_/NixJ727_2l_meqealkDUGK3--