Re: [PATCH] sparc: iommu/pci_sun4v: fix page alignment in dma mapping

["Leon Romanovsky" <leon@kernel.org>]

On Tue, Feb 17, 2026, at 19:33, Stian Halseth wrote:
> Hi Leon,
>
>
> On Tue, 2026-02-17 at 19:25 +0200, Leon Romanovsky wrote:
>> 
>> 
>> On Tue, Feb 17, 2026, at 19:16, John Paul Adrian Glaubitz wrote:
>> > Hi Stian,
>> > 
>> > On Tue, 2026-02-17 at 17:48 +0100, Stian Halseth wrote:
>> > > Thanks for the review and suggestions.
>> > > 
>> > > On Tue, 2026-02-17 at 17:38 +0100, John Paul Adrian Glaubitz
>> > > wrote:
>> > > > Hi Stian,
>> > > > 
>> > > > please rephrase the subject to:
>> > > > 
>> > > >  sparc: Fix page alignment in dma mapping
>> > > > 
>> > > > Your patch is not specific to sun4v but also fixes generic
>> > > > sparc
>> > > > code,
>> > > > so you should remove the part "iommu/pci_sun4v:" from the
>> > > > subject.
>> > > > 
>> > > Understood — I will update the patch subject as suggested.
>> > > > On Tue, 2026-02-17 at 17:21 +0100, stian@itx.no wrote:
>> > > > > From: Stian Halseth <stian@itx.no>
>> > > > > 
>> > > > > 'phys' may include an offset within the page, while
>> > > > > 'base_paddr' is
>> > > > > already page-aligned.
>> > > > > 
>> > > > > This caused incorrect DMA mapping in dma_4u_map_phys and
>> > > > > dma_4v_map_phys.
>> > > > > 
>> > > > > Fix both functions by masking phys with IO_PAGE_MASK or
>> > > > > subtracting
>> > > > > the page offset.
>> > > > 
>> > > > Please remove the newlines between your sentences, they're not
>> > > > necessary
>> > > > and also trim the lines at 80 columns.
>> > > 
>> > > Will do — I’ll reformat the commit message to 80-column lines
>> > > and remove extra newlines.
>> > 
>> > Perfect! I have nothing to add. Let's have Andreas review your
>> > patch ;-).
>> 
>> Please add Fixes line, so the patch will be taken to stable@ in
>> automatic way.
> I currently have:
> Fixes: 38c0d0ebf520 ("sparc: Use physical address DMA mapping")
>
> Is this sufficient, or do I need to add something else?

Ohh, you added extra line between signed-of-by and fixes line.

Just remove that extra blank line.

Thanks 

>> 
>> Thanks 
>> 
>> > 
>> > Adrian
>> > 
>> > -- 
>> >  .''`.  John Paul Adrian Glaubitz
>> > : :' :  Debian Developer
>> > `. `'   Physicist
>> >   `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913
>
> -- 
> Best regards
> Stian Halseth
> ​