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[69.131.150.190]) by smtp.gmail.com with ESMTPSA id 00721157ae682-7b9ee99b672sm48367907b3.29.2026.04.20.11.46.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Apr 2026 11:46:19 -0700 (PDT) Message-ID: <08ad2301-3163-4497-8869-fa4cea30b384@gmail.com> Date: Mon, 20 Apr 2026 14:46:15 -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 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> 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: <964c3670-fad3-44ce-bd93-2057bca2dcb8@amd.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------UO7W0PHisfTunOflIlWzKcyO" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --------------UO7W0PHisfTunOflIlWzKcyO Content-Type: multipart/mixed; boundary="------------J0Ikx2XPeEGPGmR0bq5owBjA"; protected-headers="v1" Message-ID: <08ad2301-3163-4497-8869-fa4cea30b384@gmail.com> Date: Mon, 20 Apr 2026 14:46:15 -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 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> 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: <964c3670-fad3-44ce-bd93-2057bca2dcb8@amd.com> --------------J0Ikx2XPeEGPGmR0bq5owBjA Content-Type: multipart/mixed; boundary="------------DQrFbbCzHC2DaqSP7y0lzlLn" --------------DQrFbbCzHC2DaqSP7y0lzlLn Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable 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 subset= >>>> of VRAM at any given time. If unmapped VRAM is accessed the gues= t >>>> 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 shuffle= d in and out of the CPU accessible window of VRAM on demand. >> >> How much is this going to hurt performance? >=20 > Hard to say, resizing the BAR can easily give you 10-15% more performan= ce on some use cases. >=20 > But that involves physically transferring the data using a DMA. For thi= s solution we basically only have to we basically only have to transfer a= few messages between host and guest. >=20 > No idea how performant that is. In this use-case, 20-30% performance penalties are likely to be "business as usual". 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. >>>> 2. Pretend that resizable BAR is not enabled, so the guest doesn't >>>> think it can map much of VRAM at once. If resizable BAR is enabl= ed >>>> on the host, it might be possible to split the large BAR mapping >>>> in a lot of ways. >>> >>> That won't work. The userspace parts of the driver stack don't care h= ow large the BAR to access VRAM with the CPU is. >>> >>> The expectation is that the kernel driver makes thing CPU accessible = as needed in the page fault handler. >>> >>> It is still a good idea for your solution #1 to give the amount of "p= in-able" VRAM to the userspace stack as CPU visible VRAM limit so that te= st cases and applications try to lower their usage of VRAM, e.g. use syst= em memory bounce buffers when possible. >> >> That makes sense. >> >>>> Or does Xen really need to allow the host to handle guest page fault= s? >>>> That adds a huge amount of complexity to trusted and security-critic= al >>>> parts of the system, so it really is a last resort. Putting the >>>> complexity in to the guest virtio-GPU driver is vastly preferable if= >>>> it can be made to work well. >>> >>> Well the nested page fault handling KVM offers has proven to be extre= mely useful. So when XEN can't do this it is clearly lacking an important= feature. >> >> I agree. However, it is a lot of work to implement, which is why I'm >> looking for alternatives if possible. >> >> KVM is part of the Linux kernel, so it can just call the Linux kernel >> functions used to handle userspace page faults. Xen is separate from >> Linux, so it can't do that. Instead, it will need to: >> >> 1. Determine that the fault needs to be handled by another VM, and >> the ID of the VM that needs to handle the fault. >> 2. Send a message to the VM asking it to handle the fault. >> 3. Block the vCPU until it gets a response. >> >> Then the VM owning the memory will need to call the page fault handler= >> and provide the memory to Xen. Xen then needs to: >> >> 4. Map the memory into the nested page tables of the VM that faulted. >> 5. Resume the vCPU. >> >>> But I have one question: When XEN has a problem handling faults from = the guest on the host then how does that work for system memory mappings?= >>> >>> There is really no difference between VRAM and system memory in the h= andling 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). >> 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. >=20 > No, that doesn't work with system memory allocations of GPU drivers eit= her. >=20 > We already had it multiple times that people tried to be clever and inc= remented the page reference counter on driver allocated system memory and= were totally surprised that this can result in security issues and data = corruption. >=20 > I seriously hope that this isn't the case here again. As far as I know = XEN already has support for accessing VMAs with VM_PFN or otherwise I don= 't know how driver allocated system memory access could potentially work.= >=20 > Accessing VRAM is pretty much the same use case as far as I can see. >=20 > 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? 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. 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 Sincerely, Demi Marie Obenour (she/her/hers) --------------DQrFbbCzHC2DaqSP7y0lzlLn 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 BtDQbabt7aNEOaAJdE7to0AH3T/Bvwzcp0ZJtBk0EM6YeMLtotUut7h2Bkg1b//r 6bTBswMBXVJ5H44Qf0+eKeUg7whSC9qpYOzzrm7+0r9F5u3qF8ZTx55TJc2g656C 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SIGNATURE----- iQIzBAEBCgAdFiEEopQtqVJW1aeuo9/sszaHOrMp8lMFAmnmdHcACgkQszaHOrMp 8lMvCBAAiEpdcmZepZcksF1OYgnp7QuUn/aJGxwxt9Ioti8YOzvBGPNUuAGiqSj6 tylnRMxnDo74nCvIGjRRAX8oQ6JVAMHuf+GguCWqsb5alDnP3G3GpSTSeaUg+cc9 OFK7KEzuOHHz1Nawu315h8otumTxQKwR0TiwO2tqb8jYYWxgVuU/zExXF70uU1ju OP1TUbVWegATUpRJuX05pQoGcy6Go/4zfFGj/ipLug0IRW0X3scAFjOpeTYGPlcW 8doVY/lLQQ3ORE2D3XVW638W7YMQsD3ahOh2rPu9/Jj8FOYcWQXNy1KfEW5l1AYF tuDU9UraCuZCat5Q+Pv1l7fLCQrwqyOqHsq9gIKo/G84RGeixO9QAHQojRpr7C+n lq/pL7psahiVHfH3N7auAd8a0OBqYbdjmxlOPBJWlOiWPlcWtcUH4S3z8JoMBM7t AQR6QQfuzSF4fK6XyW/F9nm4Fd50Pnt2odQt/jDEhEyxLys76PkXNQUuA0Jr6rCT +KsqEr3lFaNX2QWPKdY5p0cyTjdQspMrrhnHCOLygt1xdmqXqH6+P72qW0wIZkFw 98K7aolksqQ0Rzh2TclUJyFTrUSYdNKlmebZZ5e9TvUO72JturfYKlbRnxgSm5Mk rV44denq+79l0+sOY8PjqCLS/Fnsmr5qeD/nydHS+esGhReGKwM= =0mmn -----END PGP SIGNATURE----- --------------UO7W0PHisfTunOflIlWzKcyO--