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[69.131.150.190]) by smtp.gmail.com with ESMTPSA id 956f58d0204a3-65314b2845asm5687206d50.3.2026.04.20.12.12.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Apr 2026 12:12:29 -0700 (PDT) Message-ID: <686713fc-c762-4b1b-88b2-d486d4f38ac6@gmail.com> Date: Mon, 20 Apr 2026 15:12:25 -0400 Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Pinned, non-revocable mappings of VRAM: will bad things happen? To: =?UTF-8?Q?Christian_K=C3=B6nig?= , dri-devel@lists.freedesktop.org, Xen developer discussion , linux-media@vger.kernel.org Cc: Val Packett , Suwit Semal , "Pelloux-Prayer, Pierre-Eric" References: <4751cf03-d3c1-4d5d-af8e-39ad7c8ffb84@amd.com> <7472bfcf-8c22-4ac7-b903-a883cdb8f1c6@gmail.com> <8fe8b78b-5294-4319-af92-a4fb00527417@amd.com> <8846bac5-77ff-4439-ac5c-c33cdb4a94e3@gmail.com> <964c3670-fad3-44ce-bd93-2057bca2dcb8@amd.com> <08ad2301-3163-4497-8869-fa4cea30b384@gmail.com> Content-Language: en-US From: Demi Marie Obenour Autocrypt: addr=demiobenour@gmail.com; keydata= xsFNBFp+A0oBEADffj6anl9/BHhUSxGTICeVl2tob7hPDdhHNgPR4C8xlYt5q49yB+l2nipd aq+4Gk6FZfqC825TKl7eRpUjMriwle4r3R0ydSIGcy4M6eb0IcxmuPYfbWpr/si88QKgyGSV Z7GeNW1UnzTdhYHuFlk8dBSmB1fzhEYEk0RcJqg4AKoq6/3/UorR+FaSuVwT7rqzGrTlscnT DlPWgRzrQ3jssesI7sZLm82E3pJSgaUoCdCOlL7MMPCJwI8JpPlBedRpe9tfVyfu3euTPLPx wcV3L/cfWPGSL4PofBtB8NUU6QwYiQ9Hzx4xOyn67zW73/G0Q2vPPRst8LBDqlxLjbtx/WLR 6h3nBc3eyuZ+q62HS1pJ5EvUT1vjyJ1ySrqtUXWQ4XlZyoEFUfpJxJoN0A9HCxmHGVckzTRl 5FMWo8TCniHynNXsBtDQbabt7aNEOaAJdE7to0AH3T/Bvwzcp0ZJtBk0EM6YeMLtotUut7h2 Bkg1b//r6bTBswMBXVJ5H44Qf0+eKeUg7whSC9qpYOzzrm7+0r9F5u3qF8ZTx55TJc2g656C 9a1P1MYVysLvkLvS4H+crmxA/i08Tc1h+x9RRvqba4lSzZ6/Tmt60DPM5Sc4R0nSm9BBff0N m0bSNRS8InXdO1Aq3362QKX2NOwcL5YaStwODNyZUqF7izjK4QARAQABzTxEZW1pIE1hcmll IE9iZW5vdXIgKGxvdmVyIG9mIGNvZGluZykgPGRlbWlvYmVub3VyQGdtYWlsLmNvbT7CwXgE EwECACIFAlp+A0oCGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJELKItV//nCLBhr8Q AK/xrb4wyi71xII2hkFBpT59ObLN+32FQT7R3lbZRjVFjc6yMUjOb1H/hJVxx+yo5gsSj5LS 9AwggioUSrcUKldfA/PKKai2mzTlUDxTcF3vKx6iMXKA6AqwAw4B57ZEJoMM6egm57TV19kz PMc879NV2nc6+elaKl+/kbVeD3qvBuEwsTe2Do3HAAdrfUG/j9erwIk6gha/Hp9yZlCnPTX+ VK+xifQqt8RtMqS5R/S8z0msJMI/ajNU03kFjOpqrYziv6OZLJ5cuKb3bZU5aoaRQRDzkFIR 6aqtFLTohTo20QywXwRa39uFaOT/0YMpNyel0kdOszFOykTEGI2u+kja35g9TkH90kkBTG+a EWttIht0Hy6YFmwjcAxisSakBuHnHuMSOiyRQLu43ej2+mDWgItLZ48Mu0C3IG1seeQDjEYP tqvyZ6bGkf2Vj+L6wLoLLIhRZxQOedqArIk/Sb2SzQYuxN44IDRt+3ZcDqsPppoKcxSyd1Ny 2tpvjYJXlfKmOYLhTWs8nwlAlSHX/c/jz/ywwf7eSvGknToo1Y0VpRtoxMaKW1nvH0OeCSVJ itfRP7YbiRVc2aNqWPCSgtqHAuVraBRbAFLKh9d2rKFB3BmynTUpc1BQLJP8+D5oNyb8Ts4x Xd3iV/uD8JLGJfYZIR7oGWFLP4uZ3tkneDfYzsFNBFp+A0oBEAC9ynZI9LU+uJkMeEJeJyQ/ 8VFkCJQPQZEsIGzOTlPnwvVna0AS86n2Z+rK7R/usYs5iJCZ55/JISWd8xD57ue0eB47bcJv VqGlObI2DEG8TwaW0O0duRhDgzMEL4t1KdRAepIESBEA/iPpI4gfUbVEIEQuqdqQyO4GAe+M kD0Hy5JH/0qgFmbaSegNTdQg5iqYjRZ3ttiswalql1/iSyv1WYeC1OAs+2BLOAT2NEggSiVO txEfgewsQtCWi8H1SoirakIfo45Hz0tk/Ad9ZWh2PvOGt97Ka85o4TLJxgJJqGEnqcFUZnJJ riwoaRIS8N2C8/nEM53jb1sH0gYddMU3QxY7dYNLIUrRKQeNkF30dK7V6JRH7pleRlf+wQcN fRAIUrNlatj9TxwivQrKnC9aIFFHEy/0mAgtrQShcMRmMgVlRoOA5B8RTulRLCmkafvwuhs6 dCxN0GNAORIVVFxjx9Vn7OqYPgwiofZ6SbEl0hgPyWBQvE85klFLZLoj7p+joDY1XNQztmfA rnJ9x+YV4igjWImINAZSlmEcYtd+xy3Li/8oeYDAqrsnrOjb+WvGhCykJk4urBog2LNtcyCj kTs7F+WeXGUo0NDhbd3Z6AyFfqeF7uJ3D5hlpX2nI9no/ugPrrTVoVZAgrrnNz0iZG2DVx46 x913pVKHl5mlYQARAQABwsFfBBgBAgAJBQJafgNKAhsMAAoJELKItV//nCLBwNIP/AiIHE8b oIqReFQyaMzxq6lE4YZCZNj65B/nkDOvodSiwfwjjVVE2V3iEzxMHbgyTCGA67+Bo/d5aQGj gn0TPtsGzelyQHipaUzEyrsceUGWYoKXYyVWKEfyh0cDfnd9diAm3VeNqchtcMpoehETH8fr RHnJdBcjf112PzQSdKC6kqU0Q196c4Vp5HDOQfNiDnTf7gZSj0BraHOByy9LEDCLhQiCmr+2 E0rW4tBtDAn2HkT9uf32ZGqJCn1O+2uVfFhGu6vPE5qkqrbSE8TG+03H8ecU2q50zgHWPdHM OBvy3EhzfAh2VmOSTcRK+tSUe/u3wdLRDPwv/DTzGI36Kgky9MsDC5gpIwNbOJP2G/q1wT1o Gkw4IXfWv2ufWiXqJ+k7HEi2N1sree7Dy9KBCqb+ca1vFhYPDJfhP75I/VnzHVssZ/rYZ9+5 1yDoUABoNdJNSGUYl+Yh9Pw9pE3Kt4EFzUlFZWbE4xKL/NPno+z4J9aWemLLszcYz/u3XnbO vUSQHSrmfOzX3cV4yfmjM5lewgSstoxGyTx2M8enslgdXhPthZlDnTnOT+C+OTsh8+m5tos8 HQjaPM01MKBiAqdPgksm1wu2DrrwUi6ChRVTUBcj6+/9IJ81H2P2gJk3Ls3AVIxIffLoY34E +MYSfkEjBz0E8CLOcAw7JIwAaeBT In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------oLcefsVzkSfrb6uaB7hzzgLl" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --------------oLcefsVzkSfrb6uaB7hzzgLl Content-Type: multipart/mixed; boundary="------------h9T0I0ygGOGJXLDPzJnCSWj0"; protected-headers="v1" Message-ID: <686713fc-c762-4b1b-88b2-d486d4f38ac6@gmail.com> Date: Mon, 20 Apr 2026 15:12:25 -0400 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Pinned, non-revocable mappings of VRAM: will bad things happen? To: =?UTF-8?Q?Christian_K=C3=B6nig?= , dri-devel@lists.freedesktop.org, Xen developer discussion , linux-media@vger.kernel.org Cc: Val Packett , Suwit Semal , "Pelloux-Prayer, Pierre-Eric" References: <4751cf03-d3c1-4d5d-af8e-39ad7c8ffb84@amd.com> <7472bfcf-8c22-4ac7-b903-a883cdb8f1c6@gmail.com> <8fe8b78b-5294-4319-af92-a4fb00527417@amd.com> <8846bac5-77ff-4439-ac5c-c33cdb4a94e3@gmail.com> <964c3670-fad3-44ce-bd93-2057bca2dcb8@amd.com> <08ad2301-3163-4497-8869-fa4cea30b384@gmail.com> Content-Language: en-US From: Demi Marie Obenour Autocrypt: addr=demiobenour@gmail.com; keydata= xsFNBFp+A0oBEADffj6anl9/BHhUSxGTICeVl2tob7hPDdhHNgPR4C8xlYt5q49yB+l2nipd aq+4Gk6FZfqC825TKl7eRpUjMriwle4r3R0ydSIGcy4M6eb0IcxmuPYfbWpr/si88QKgyGSV Z7GeNW1UnzTdhYHuFlk8dBSmB1fzhEYEk0RcJqg4AKoq6/3/UorR+FaSuVwT7rqzGrTlscnT DlPWgRzrQ3jssesI7sZLm82E3pJSgaUoCdCOlL7MMPCJwI8JpPlBedRpe9tfVyfu3euTPLPx wcV3L/cfWPGSL4PofBtB8NUU6QwYiQ9Hzx4xOyn67zW73/G0Q2vPPRst8LBDqlxLjbtx/WLR 6h3nBc3eyuZ+q62HS1pJ5EvUT1vjyJ1ySrqtUXWQ4XlZyoEFUfpJxJoN0A9HCxmHGVckzTRl 5FMWo8TCniHynNXsBtDQbabt7aNEOaAJdE7to0AH3T/Bvwzcp0ZJtBk0EM6YeMLtotUut7h2 Bkg1b//r6bTBswMBXVJ5H44Qf0+eKeUg7whSC9qpYOzzrm7+0r9F5u3qF8ZTx55TJc2g656C 9a1P1MYVysLvkLvS4H+crmxA/i08Tc1h+x9RRvqba4lSzZ6/Tmt60DPM5Sc4R0nSm9BBff0N m0bSNRS8InXdO1Aq3362QKX2NOwcL5YaStwODNyZUqF7izjK4QARAQABzTxEZW1pIE1hcmll IE9iZW5vdXIgKGxvdmVyIG9mIGNvZGluZykgPGRlbWlvYmVub3VyQGdtYWlsLmNvbT7CwXgE EwECACIFAlp+A0oCGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJELKItV//nCLBhr8Q AK/xrb4wyi71xII2hkFBpT59ObLN+32FQT7R3lbZRjVFjc6yMUjOb1H/hJVxx+yo5gsSj5LS 9AwggioUSrcUKldfA/PKKai2mzTlUDxTcF3vKx6iMXKA6AqwAw4B57ZEJoMM6egm57TV19kz PMc879NV2nc6+elaKl+/kbVeD3qvBuEwsTe2Do3HAAdrfUG/j9erwIk6gha/Hp9yZlCnPTX+ VK+xifQqt8RtMqS5R/S8z0msJMI/ajNU03kFjOpqrYziv6OZLJ5cuKb3bZU5aoaRQRDzkFIR 6aqtFLTohTo20QywXwRa39uFaOT/0YMpNyel0kdOszFOykTEGI2u+kja35g9TkH90kkBTG+a EWttIht0Hy6YFmwjcAxisSakBuHnHuMSOiyRQLu43ej2+mDWgItLZ48Mu0C3IG1seeQDjEYP tqvyZ6bGkf2Vj+L6wLoLLIhRZxQOedqArIk/Sb2SzQYuxN44IDRt+3ZcDqsPppoKcxSyd1Ny 2tpvjYJXlfKmOYLhTWs8nwlAlSHX/c/jz/ywwf7eSvGknToo1Y0VpRtoxMaKW1nvH0OeCSVJ itfRP7YbiRVc2aNqWPCSgtqHAuVraBRbAFLKh9d2rKFB3BmynTUpc1BQLJP8+D5oNyb8Ts4x Xd3iV/uD8JLGJfYZIR7oGWFLP4uZ3tkneDfYzsFNBFp+A0oBEAC9ynZI9LU+uJkMeEJeJyQ/ 8VFkCJQPQZEsIGzOTlPnwvVna0AS86n2Z+rK7R/usYs5iJCZ55/JISWd8xD57ue0eB47bcJv VqGlObI2DEG8TwaW0O0duRhDgzMEL4t1KdRAepIESBEA/iPpI4gfUbVEIEQuqdqQyO4GAe+M kD0Hy5JH/0qgFmbaSegNTdQg5iqYjRZ3ttiswalql1/iSyv1WYeC1OAs+2BLOAT2NEggSiVO txEfgewsQtCWi8H1SoirakIfo45Hz0tk/Ad9ZWh2PvOGt97Ka85o4TLJxgJJqGEnqcFUZnJJ riwoaRIS8N2C8/nEM53jb1sH0gYddMU3QxY7dYNLIUrRKQeNkF30dK7V6JRH7pleRlf+wQcN fRAIUrNlatj9TxwivQrKnC9aIFFHEy/0mAgtrQShcMRmMgVlRoOA5B8RTulRLCmkafvwuhs6 dCxN0GNAORIVVFxjx9Vn7OqYPgwiofZ6SbEl0hgPyWBQvE85klFLZLoj7p+joDY1XNQztmfA rnJ9x+YV4igjWImINAZSlmEcYtd+xy3Li/8oeYDAqrsnrOjb+WvGhCykJk4urBog2LNtcyCj kTs7F+WeXGUo0NDhbd3Z6AyFfqeF7uJ3D5hlpX2nI9no/ugPrrTVoVZAgrrnNz0iZG2DVx46 x913pVKHl5mlYQARAQABwsFfBBgBAgAJBQJafgNKAhsMAAoJELKItV//nCLBwNIP/AiIHE8b oIqReFQyaMzxq6lE4YZCZNj65B/nkDOvodSiwfwjjVVE2V3iEzxMHbgyTCGA67+Bo/d5aQGj gn0TPtsGzelyQHipaUzEyrsceUGWYoKXYyVWKEfyh0cDfnd9diAm3VeNqchtcMpoehETH8fr RHnJdBcjf112PzQSdKC6kqU0Q196c4Vp5HDOQfNiDnTf7gZSj0BraHOByy9LEDCLhQiCmr+2 E0rW4tBtDAn2HkT9uf32ZGqJCn1O+2uVfFhGu6vPE5qkqrbSE8TG+03H8ecU2q50zgHWPdHM OBvy3EhzfAh2VmOSTcRK+tSUe/u3wdLRDPwv/DTzGI36Kgky9MsDC5gpIwNbOJP2G/q1wT1o Gkw4IXfWv2ufWiXqJ+k7HEi2N1sree7Dy9KBCqb+ca1vFhYPDJfhP75I/VnzHVssZ/rYZ9+5 1yDoUABoNdJNSGUYl+Yh9Pw9pE3Kt4EFzUlFZWbE4xKL/NPno+z4J9aWemLLszcYz/u3XnbO vUSQHSrmfOzX3cV4yfmjM5lewgSstoxGyTx2M8enslgdXhPthZlDnTnOT+C+OTsh8+m5tos8 HQjaPM01MKBiAqdPgksm1wu2DrrwUi6ChRVTUBcj6+/9IJ81H2P2gJk3Ls3AVIxIffLoY34E +MYSfkEjBz0E8CLOcAw7JIwAaeBT In-Reply-To: --------------h9T0I0ygGOGJXLDPzJnCSWj0 Content-Type: multipart/mixed; boundary="------------tPVaFr0yvTUet01h9p9LgABE" --------------tPVaFr0yvTUet01h9p9LgABE Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 4/20/26 14:53, Christian K=C3=B6nig wrote: > On 4/20/26 20:46, Demi Marie Obenour wrote: >> On 4/20/26 13:58, Christian K=C3=B6nig wrote: >>> On 4/20/26 19:03, Demi Marie Obenour wrote: >>>> On 4/20/26 04:49, Christian K=C3=B6nig wrote: >>>>> On 4/17/26 21:35, Demi Marie Obenour wrote: >>> ... >>>>>> Are any of the following reasonable options? >>>>>> >>>>>> 1. Change the guest kernel to only map (and thus pin) a small subs= et >>>>>> of VRAM at any given time. If unmapped VRAM is accessed the gu= est >>>>>> traps the page fault, evicts an old VRAM mapping, and creates a= >>>>>> new one. >>>>> >>>>> Yeah, that could potentially work. >>>>> >>>>> This is basically what we do on the host kernel driver when we can'= t resize the BAR for some reason. In that use case VRAM buffers are shuff= led in and out of the CPU accessible window of VRAM on demand. >>>> >>>> How much is this going to hurt performance? >>> >>> Hard to say, resizing the BAR can easily give you 10-15% more perform= ance on some use cases. >>> >>> But that involves physically transferring the data using a DMA. For t= his solution we basically only have to we basically only have to transfer= a few messages between host and guest. >>> >>> No idea how performant that is. >> >> In this use-case, 20-30% performance penalties are likely to be >> "business as usual". >=20 > Well that is quite a bit. >=20 >> Close to native performance would be ideal, but >> to be useful it just needs to beat software rendering by a wide margin= , >> and not cause data corruption or vulnerabilities. >=20 > That should still easily be the case, even trivial use cases are multip= le magnitudes faster on GPUs compared to software rendering. Makes sense. If only GPUs supported easy and flexible virtualization the= way CPUs do :(. >>>> >>>>> But I have one question: When XEN has a problem handling faults fro= m the guest on the host then how does that work for system memory mapping= s? >>>>> >>>>> There is really no difference between VRAM and system memory in the= handling for the GPU driver stack. >>>>> >>>>> Regards, >>>>> Christian. >>>> >>>> Generally, Xen makes the frontend (usually an unprivileged VM) >>>> responsible for providing mappings to the backend (usually the host)= =2E >>>> That is possible with system RAM but not with VRAM, because Xen has >>>> no awareness of VRAM. To Xen, VRAM is just a PCI BAR. >>> >>> No, that doesn't work with system memory allocations of GPU drivers e= ither. >>> >>> We already had it multiple times that people tried to be clever and i= ncremented the page reference counter on driver allocated system memory a= nd were totally surprised that this can result in security issues and dat= a corruption. >>> >>> I seriously hope that this isn't the case here again. As far as I kno= w XEN already has support for accessing VMAs with VM_PFN or otherwise I d= on't know how driver allocated system memory access could potentially wor= k. >>> >>> Accessing VRAM is pretty much the same use case as far as I can see. >>> >>> Regards, >>> Christian. >> >> The Xen-native approach would be for system memory allocations to >> be made using the Xen driver and then imported into the virtio-GPU >> driver via dmabuf. Is there any chance this could be made to happen? >=20 > That could be. Adding Pierre-Eric to comment since he knows that use mu= ch better than I do. >=20 >> If it's a lost cause, then how much is the memory overhead of pinning >> everything ever used in a dmabuf? It should be possible to account >> pinned host memory against a guest's quota, but if that leads to an >> unusable system it isn't going to be good. >=20 > That won't work at all. >=20 > We have use cases where you *must* migrate a DMA-buf to VRAM or otherwi= se the GPU can't use it. >=20 > A simple scanout to a monitor is such an use case for example, that is = usually not possible from system memory. Direct scanout isn't a concern here. >> Is supporting page faults in Xen the only solution that will be viable= >> long-term, considering the tolerance for very substantial performance >> overheads compared to native? AAA gaming isn't the initial goal here.= >> Qubes OS already supports PCI passthrough for that. >=20 > We have AAA gaming working on XEN through native context working for qu= ite a while. >=20 > Pierre-Eric can tell you more about that. >=20 > Regards, > Christian. I've heard of that, but last I checked it required downstream patches to Xen, Linux, and QEMU. I don't know if any of those have been upstreamed since, but I believe that upstreaming the Xen and Linux patches (or rewriting them and upstreaming the rewritten version) would be necessary. Qubes OS (which I don't work for anymore but still want to help with this) almost certainly won't be using QEMU for GPU stuff. --=20 Sincerely, Demi Marie Obenour (she/her/hers) --------------tPVaFr0yvTUet01h9p9LgABE Content-Type: application/pgp-keys; name="OpenPGP_0xB288B55FFF9C22C1.asc" Content-Disposition: attachment; filename="OpenPGP_0xB288B55FFF9C22C1.asc" Content-Description: OpenPGP public key Content-Transfer-Encoding: quoted-printable -----BEGIN PGP PUBLIC KEY BLOCK----- xsFNBFp+A0oBEADffj6anl9/BHhUSxGTICeVl2tob7hPDdhHNgPR4C8xlYt5q49y B+l2nipdaq+4Gk6FZfqC825TKl7eRpUjMriwle4r3R0ydSIGcy4M6eb0IcxmuPYf bWpr/si88QKgyGSVZ7GeNW1UnzTdhYHuFlk8dBSmB1fzhEYEk0RcJqg4AKoq6/3/ UorR+FaSuVwT7rqzGrTlscnTDlPWgRzrQ3jssesI7sZLm82E3pJSgaUoCdCOlL7M MPCJwI8JpPlBedRpe9tfVyfu3euTPLPxwcV3L/cfWPGSL4PofBtB8NUU6QwYiQ9H zx4xOyn67zW73/G0Q2vPPRst8LBDqlxLjbtx/WLR6h3nBc3eyuZ+q62HS1pJ5EvU T1vjyJ1ySrqtUXWQ4XlZyoEFUfpJxJoN0A9HCxmHGVckzTRl5FMWo8TCniHynNXs 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Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="OpenPGP_signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEopQtqVJW1aeuo9/sszaHOrMp8lMFAmnmepoACgkQszaHOrMp 8lOe5w/+KjpGlyI9G3fHlW7AUGjL8ojXIHalSkjbdJ1ErYaySIUYiJ7iBnotUcW+ nOdIAZv6EoqBQrrieYY88OhX2t5Aqu8b00Fviwb/nWFklsbEMRTIahvWNJJokeV/ poveO3O2A7dnwtoyZiLXXpDzQ2aPBX9GFOcamqnO2chA3AjftpJtjrfZJYPmJImE 8/SVjJAKuCTM0/Mh9cxBgwYrjVvXs0rfWG1ZzOD1FAVWd/tlDnMwmvC9/EFSCXh2 AXCjM+YJEscggLsV2mXlZ3oLaUShUqkmLCMNSvdEzCDPFdYU7O3d5axcuP19g6VD BirBlfddKETzxiuxv15v5jxC7vuVSlMRBDdFkA8s8/GAvQ2ZPo+3FHOVlCZ+rKUR bHLLaxGmXTGG7JGQe33SgaHA11yP2aHkEhMVyqQ0CmbhgE/In1XDh1D27TcsB+Zs fsEU2dmdafcHRkbTY8LHBLyYjvFt4Q87ml0C5JIzJmZitDo0CoeR5I9mQjjRqzgV fpappRRkPuGZN33R2pD51ZmbfXHeefWxtaEBb+M7lvXEje2I0huUxUn7L2huDWjQ KEnHt4qqS1kRzqhSgQJC56a5MjtjnS0cOVYgzvQtxLUFMh1IAwtefJ2h9LuQKbWl F+tpIy9kl2RI4YA4oJ+MUZDdsrNiyLM+M6FD3XeHpRn6HTO/FQI= =Uhuz -----END PGP SIGNATURE----- --------------oLcefsVzkSfrb6uaB7hzzgLl--