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Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > On Mon, 17 Aug 2026 10:50:35 -0500, Frank Li wrote: > > On Sun, Aug 16, 2026 at 07:10:44AM +0200, Michal Pecio wrote: > > > No realistic chance of the dev->dma_mask check (below) giving -EIO? > > > > dma_mask is pointer, which already initilized by bus driver before > > call to probe. > > > > For example > > > > https://elixir.bootlin.com/linux/v7.1.8/source/drivers/base/platform.c#L634 > > > > If you find one, which bus driver have not init it, please high light > > it. > > > > > > dma_supported() will call dma_direct_supported or iommux's > > > > dma_supported call back function. > > > > > > Aapparently, it may also use some 'dma_map_ops' and there is a bunch > > > of those spread over drivers/ and arch/. But I gather they are > > > expected to behave similarly as the functions named above? > > > > I grep it and checked at that time, all return 1 when >= 32. Now more > > powerfull check tools avaible, you can double check it. > > Thank you. Sounds like it should work then, though I think that > checking return status won't harm, just to cover unusual cases like > regression in some obscure arch or people with buggy out of tree > patches (which they "forget" to mention they are using). Now, prefer don't check when >= 32 to keep code clean. Frank > > Regards, > Michal