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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: mobileye.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: VI1PR09MB2333.eurprd09.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: f7da2c6e-6909-4ec1-0a17-08dcdaee4bef X-MS-Exchange-CrossTenant-originalarrivaltime: 22 Sep 2024 10:06:59.0735 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 4f85ba13-6953-46a6-9c5b-7599fd80e9aa X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: N+hbhTxHYZu+E2jKhnd5Lr/thuUxLBF80kaMQwwnj9AOwLOjQg/vXZwtrS6RqZ8k4VFu1iV92OTuwWGnT/Tlpg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB8PR09MB3738 X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: E599440005 X-Stat-Signature: fitgk41km7s3dm89owc69ftecgyqqng9 X-HE-Tag: 1726999623-250613 X-HE-Meta: U2FsdGVkX19GdIAVKgRXP/uMBRCw6i+4wHceh1iPItXGmJehyXtwJo0Wb9fGNmrxJF7z5Hsx0btfqIUjYiayPtiCtabumBnjEq1mTE+ys1lag7MrArC7SDUpf4keO30LoSYIBVzT/HQydKwp0gR3ix35XuhAKkP/zXN2k5brpF0OS9RNCgH00yJDc3e5fs2LcoyW5JbG+DWfgp13FmEJ6Uys0jN+qL9AQopBEDhMOTAXtXSq5Loc/aKWHfBsbLynNj7otCSVCQwZERs/P7DCso5L7JHtVPwZb0eGPOOAEOp6mg+PZSlAI8buA+Sa5KQo9WcHvGf0sYeU3Z50kDnvnl7P6nrv6ROqdvFgaF3VwZvNijq2kAfPr51qa3/3NkCcQvATPaeNqPddZ55KHdbnNrEsvgPkht7kYz7oG3uu+eEGiqQ9FFdoox0D4HqH6X5EYnOB6MK6qhGt7hzSBl1O93wE3Rgkll2x1OW93KP8uAzIjMLrHlv1+6yDwZ/wGAfhYrbvSvzo92rWD4gku7IH+Pp6xbI4oRAbtb5HSMUM6kguscroKOanQLryEWkdmnvYsTK17TceHLxubUE00wBfL8F0u6udIE/7sNI+3RbO0/oBT9ErwBMcfrDRv7/2vSzva9BvNSWqpE4QYsxD93YEju7PICUHumw8hiWJx2mInC6BkiwLgWtqKUD6cR96qholkRRBhirAzBakVfNAaDdALyN+ELlh8NRMEVuBkeFAkts+9tUWz4ifuVSo1ImBUOxrhI4+WI7IjDaPtIm2YkTAzFKzAcTcNm2TcGI+xeT7tQHx80Y8nqoMn0XwDDm7HdJy3sm0Ew5Rfx/fvtcwAa+MpQpZEkFnPWyudgAFNxnY3jD3U9olrCaXTDD0eLUffy2lO8zIMUKXKx031aI9XJCwypJ0AgHTsV3+k8FPcTBtXDY3W9vnt+15C9Kugm/5v0z9G9xA89k9C2kFykQHn+3 SeQApM3V +gugF4IJR4cuyS+HybctjjCLANGk7UPC767fZYCKmTwn53EhC6qo8SmjYjD1l0sQc8+dmx7jCIUjDOtZf6so8GC0R9ybF7u2ymov+MhwYGKiIKtFrwuCRb+Hz6AwzFvrZjdtGSVAlvqwJj8JAGmMbwQ0kHK732y6/pC5VjyNXIWt/Y/nzPr4Shqp5+OgNLSvVBah6H7+kJC5KB1N/fHbJURvtyBfH6Rnc0hz56jfkHleCgJE4begdHFNlHRNU7LxxzxfiTKUJDoN8B0ROKKb6KzHX67+THYm4N1580yDn+0EaPsTZvZLji7yunfby+8gJdCPU6J8r3+OM5E69nfc6FdwUL7I9cXM36GnWxbk+XRK8WWbIJ0x6/Qn8Df+EJqE1Q7CnztEDW5VmBEfVkWRh/Z3ry7KUdyH03TVhH/Q1Nwyimk5v1LrMAaaV7eVkmhltU8+PYAbT9gxux267uh+lvnGwSQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: >On Tue, Aug 27, 2024 at 02:36:11PM +0300, Vladimir Kondratiev wrote:=0A= >> It is not necessary any RISCV platform has ZONE_DMA32.=0A= =0A= >That is an odd statement.=A0 The point of ZONE_DMA32 is to make sure=0A= >that drivers can always allocate 32-bit DMAable memory, and without=0A= >ZONE_DMA32 that is very hard to provide unless you always have an=0A= >IOMMU.=0A= =0A= This is the whole point - there are platforms where you can't allocate 32-b= it=0A= dma-able memory.=0A= Unless there's IOMMU or some platform specific tricks,=0A= DMA address is same as physical address.=0A= In my example, platform has DRAM installed at address 32Gbytes.=0A= 32-bit devices would not work on such platform, and attempt to allocate=0A= ZONE_DMA32 memory fails and kernel prints warning as in my original post=0A= =0A= >ZONE_DMA32 is supposed to contain the 32-bit dma addressable memory,=0A= >not 32-bit physical.=0A= =0A= >Take a look at the changes that just went into Linus' tree for that.=0A= =0A= I re-evaluated with Linus's tree as of now (commit 88264981f208), same erro= r reported if I don't apply my patch:=0A= =0A= [ 0.191514] DMA: preallocated 512 KiB GFP_KERNEL pool for atomic allocat= ions=0A= [ 0.191524] swapper/0: page allocation failure: order:7, mode:0xcc4(GFP_= KERNEL|GFP_DMA32), nodemask=3D(null),cpuset=3D/,mem=0A= s_allowed=3D0=0A= [ 0.191546] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.11.0 #2= =0A= [ 0.191553] Hardware name: ???? (DT)=0A= [ 0.191556] Call Trace:=0A= [ 0.191560] [] dump_backtrace+0x1c/0x24=0A= [ 0.191571] [] show_stack+0x2c/0x38=0A= [ 0.191578] [] dump_stack_lvl+0x52/0x74=0A= [ 0.191584] [] dump_stack+0x14/0x1c=0A= [ 0.191589] [] warn_alloc+0xf4/0x180=0A= [ 0.191598] [] __alloc_pages_noprof+0x970/0xd94=0A= [ 0.191605] [] atomic_pool_expand+0x62/0x1f8=0A= [ 0.191615] [] __dma_atomic_pool_init+0x46/0x9e=0A= [ 0.191620] [] dma_atomic_pool_init+0x96/0x11c=0A= [ 0.191626] [] do_one_initcall+0x5c/0x1b2=0A= [ 0.191631] [] kernel_init_freeable+0x214/0x274=0A= [ 0.191636] [] kernel_init+0x1e/0x10a=0A= [ 0.191644] [] ret_from_fork+0xe/0x1c=0A= [ 0.191709] Mem-Info:=0A= [ 0.191714] active_anon:0 inactive_anon:0 isolated_anon:0=0A= [ 0.191714] active_file:0 inactive_file:0 isolated_file:0=0A= [ 0.191714] unevictable:0 dirty:0 writeback:0=0A= [ 0.191714] slab_reclaimable:26 slab_unreclaimable:742=0A= [ 0.191714] mapped:0 shmem:0 pagetables:65=0A= [ 0.191714] sec_pagetables:0 bounce:0=0A= [ 0.191714] kernel_misc_reclaimable:0=0A= [ 0.191714] free:1014355 free_pcp:0 free_cma:0=0A= [ 0.191727] 0 total pagecache pages=0A= [ 0.191730] 1048576 pages RAM=0A= [ 0.191733] 0 pages HighMem/MovableOnly=0A= [ 0.191735] 30264 pages reserved=0A= [ 0.191743] DMA: failed to allocate 496 KiB GFP_KERNEL|GFP_DMA32 pool fo= r atomic allocation=0A= =0A=