gathered from x.com:
nvidia actually exposes a GPU upload heap (mapped BAR to user-mode) in Vulkan on Ampere Altra in their drivers.
This caused app breakage for Tellusim as Ampere Altra forces mapping BARs as device mem, instead of normal NC, for things to work properly. Device mem doesn't allow unaligned accesses.
It's a quirk that Apple Silicon Macs also have, and I'm tempted to say that perhaps NV should just not expose a GPU upload heap on Altra. After all, D3D12 didn't need it for ages.
Longhorn /
npub1p2…me7pz
2024-06-02 20:13:50
Author Public Key
npub1p2yl7tnq9q3ps8a7wk23shrv97uwfgmt5953rt35rrsev8evm0nqgme7pzPublished at
2024-06-02 20:13:50Event JSON
{
"id": "a402e0e942be6fbb6af39f7947cb9e24ff8efa11aea4a25919f6896ea44d437e",
"pubkey": "0a89ff2e602822181fbe7595185c6c2fb8e4a36ba16911ae3418e1961f2cdbe6",
"created_at": 1717359230,
"kind": 1,
"tags": [
[
"proxy",
"https://mastodon.social/@never_released/112548854558955926",
"web"
],
[
"proxy",
"https://mastodon.social/users/never_released/statuses/112548854558955926",
"activitypub"
],
[
"L",
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[
"l",
"pink.momostr.activitypub:https://mastodon.social/users/never_released/statuses/112548854558955926",
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"content": "gathered from x.com:\n\nnvidia actually exposes a GPU upload heap (mapped BAR to user-mode) in Vulkan on Ampere Altra in their drivers.\n\nThis caused app breakage for Tellusim as Ampere Altra forces mapping BARs as device mem, instead of normal NC, for things to work properly. Device mem doesn't allow unaligned accesses.\n\nIt's a quirk that Apple Silicon Macs also have, and I'm tempted to say that perhaps NV should just not expose a GPU upload heap on Altra. After all, D3D12 didn't need it for ages.",
"sig": "16d608c3503bf25eb26c7dc09551bc66f2d4c16b7741f90287b56981fc600aca3e436d8dbf1fd24c7916e12961d94cce8138ebd683c2a7796b955ffe5192c242"
}