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Violators will be prosecuted for from ; Thu, 14 Nov 2019 16:18:55 -0000 Subject: Re: [RFC 17/37] DOCUMENTATION: protvirt: Instruction emulation References: <20191024114059.102802-1-frankja@linux.ibm.com> <20191024114059.102802-18-frankja@linux.ibm.com> <20191114161526.1100f4fe.cohuck@redhat.com> <20191114162024.13f17aa9@p-imbrenda.boeblingen.de.ibm.com> <20191114164136.0be3f058.cohuck@redhat.com> <20191114170313.3606d554.cohuck@redhat.com> From: Janosch Frank Date: Thu, 14 Nov 2019 17:18:49 +0100 MIME-Version: 1.0 In-Reply-To: <20191114170313.3606d554.cohuck@redhat.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="jSzyJHTUhJUIhYKSXHyzpzQKxIQBAjmA7" Message-Id: Sender: linux-s390-owner@vger.kernel.org List-ID: To: Cornelia Huck Cc: Claudio Imbrenda , kvm@vger.kernel.org, linux-s390@vger.kernel.org, thuth@redhat.com, david@redhat.com, borntraeger@de.ibm.com, mihajlov@linux.ibm.com, mimu@linux.ibm.com, gor@linux.ibm.com This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --jSzyJHTUhJUIhYKSXHyzpzQKxIQBAjmA7 Content-Type: multipart/mixed; boundary="YwqOWWR8alc2c7qxtq0Q0iLwV1d7IXMU3" --YwqOWWR8alc2c7qxtq0Q0iLwV1d7IXMU3 Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 11/14/19 5:03 PM, Cornelia Huck wrote: > On Thu, 14 Nov 2019 16:55:46 +0100 > Janosch Frank wrote: >=20 >> On 11/14/19 4:41 PM, Cornelia Huck wrote: >>> On Thu, 14 Nov 2019 16:20:24 +0100 >>> Claudio Imbrenda wrote: >>> =20 >>>> On Thu, 14 Nov 2019 16:15:26 +0100 >>>> Cornelia Huck wrote: >>>> =20 >>>>> On Thu, 24 Oct 2019 07:40:39 -0400 >>>>> Janosch Frank wrote: >=20 >>>>>> +The Secure Instruction Data Area contains instruction storage >>>>>> +data. Data for diag 500 is exempt from that and has to be moved >>>>>> +through shared buffers to KVM. =20 >>>>> >>>>> I find this paragraph a bit confusing. What does that imply for dia= g >>>>> 500 interception? Data is still present in gprs 1-4? =20 >>>> >>>> no registers are leaked in the registers. registers are always only >>>> exposed through the state description. =20 >>> >>> So, what is so special about diag 500, then? =20 >> >> That's mostly a confusion on my side. >> The SIDAD is 4k max, so we can only move IO "management" data over it >> like ORBs and stuff. My intention was to point out, that the data whic= h >> is to be transferred (disk contents, etc.) can't go over the SIDAD but= >> needs to be in a shared page. >> >> diag500 was mostly a notification mechanism without a lot of data, rig= ht? >=20 > Yes; the main information in there are the schid identifying the > subchannel, the virtqueue number, and a cookie value, all of which fit > into the registers. >=20 > So this goes via the sidad as well? >=20 Only referenced data goes over the SIDA, register values go into offset 0x380 of the SIE state description. If an instruction has an address in a register, we will receive a bogus address and the referenced data in the SIDA. SCLP has a code and an address as register values. We will get the code and a bogus address in the register area. The SCCB will be in the SIDA. --YwqOWWR8alc2c7qxtq0Q0iLwV1d7IXMU3-- --jSzyJHTUhJUIhYKSXHyzpzQKxIQBAjmA7 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEwGNS88vfc9+v45Yq41TmuOI4ufgFAl3NfmkACgkQ41TmuOI4 ufi48Q//e0H4EvQzO9zWoLAuCgPrQAya+QuTueDJ222Jovon5WsD+TqnFapFhxLL hMxTupw9OVFftzRJIhGQKHWU8RlRejJxd7nQ0vI4XMrGPDpw4wVKrzzEyIeU0uvk szs0Z1HyIgbp70b/k2ZUPCRDDgKw83jAqPhyK1ggSBK8rMg59drCHb7Ahkc2xTJi uspkJRa5H0g2gvo1OZ6ES6UCPv/eshcTtY5l3baIzUDEjNo5aqD1a4QqJk120TC5 UQM1YjXf2PAPQeVMKtIakMzIPmCvzMUEKplYrDoeBDFyzxW+AzzWAjbpqEKLu0f8 ylUnktsB+6w88MDT+kEPiW5kg9ljoz/gaLnD6zYd0ifSQkC8TvmFCt1itlsQRAx3 FTbZtQsDP4f+wu7MQeimx7q6+YdGXYmb7s0tlc59g1k2RX5KgZGKQeels6B5j/Ub PYZGEmCbyX/y97UrRGVEIaNSRCBjn8pYKARCz+bYjUYDm7GQRPPLs5rA1iSe3BG0 kp1efOktq4MBGjxHFFLZL0mhdpyxjraErjrKX8JFdu6eE93qWZDmTYwOAccLGEKt a5BBNlHtzeCvlEvh2pSrEvLeahiQa+OWU81Kpa5Tea+01yVBRlviKGOfislxN2Wv hWJq4VK9qAX5w+c9PLiu9MxdhVrXMSWrx73gsLrLfFVeJXsFsgk= =M3Vx -----END PGP SIGNATURE----- --jSzyJHTUhJUIhYKSXHyzpzQKxIQBAjmA7--