Re: [PATCH v3 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA

On Thu, Feb 27, 2020 at 10:03 AM Jason Gunthorpe wrote: > > On Thu, Feb 27, 2020 at 09:55:04AM -0800, Dan Williams wrote: > > On Thu, Feb 27, 2020 at 9:43 AM Jason Gunthorpe wrote: > > > > > > On Thu, Feb 27, 2020 at 10:21:50AM -0700, Logan Gunthorpe wrote: > > > > > > > > > > > > On 2020-02-27 1

Re: [PATCH v3 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA

On Thu, Feb 27, 2020 at 09:55:04AM -0800, Dan Williams wrote: > On Thu, Feb 27, 2020 at 9:43 AM Jason Gunthorpe wrote: > > > > On Thu, Feb 27, 2020 at 10:21:50AM -0700, Logan Gunthorpe wrote: > > > > > > > > > On 2020-02-27 10:17 a.m., Jason Gunthorpe wrote: > > > >> Instead of this, this series p

Re: [PATCH v3 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA

On Thu, Feb 27, 2020 at 9:43 AM Jason Gunthorpe wrote: > > On Thu, Feb 27, 2020 at 10:21:50AM -0700, Logan Gunthorpe wrote: > > > > > > On 2020-02-27 10:17 a.m., Jason Gunthorpe wrote: > > >> Instead of this, this series proposes a change to arch_add_memory() > > >> to take the pgprot required by

Re: [PATCH v3 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA

On 2020-02-27 10:43 a.m., Jason Gunthorpe wrote: > Hm, AFAIK WC memory is not compatible with the spinlocks/mutexs/etc in > Linux, so while it is true the memory has no side effects, there would > be surprising concurrency risks if anything in the kernel tried to > write to it. > > Not compatib

Re: [PATCH v3 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA

On 2020-02-27 10:17 a.m., Jason Gunthorpe wrote: >> Instead of this, this series proposes a change to arch_add_memory() >> to take the pgprot required by the mapping which allows us to >> explicitly set pagetable entries for P2PDMA memory to WC. > > Is there a particular reason why WC was selec

Re: [PATCH v3 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA

On Thu, Feb 27, 2020 at 10:21:50AM -0700, Logan Gunthorpe wrote: > > > On 2020-02-27 10:17 a.m., Jason Gunthorpe wrote: > >> Instead of this, this series proposes a change to arch_add_memory() > >> to take the pgprot required by the mapping which allows us to > >> explicitly set pagetable entries

Re: [PATCH v3 0/7] Allow setting caching mode in arch_add_memory() for P2PDMA

On Fri, Feb 21, 2020 at 11:24:56AM -0700, Logan Gunthorpe wrote: > Hi, > > This is v3 of the patchset which cleans up a number of minor issues > from the feedback of v2 and rebases onto v5.6-rc2. Additional feedback > is welcome. > > Thanks, > > Logan > > -- > > Changes in v3: > * Rebased ont