Re: [PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-18 Thread Christoph Hellwig
On Sun, Jun 17, 2018 at 09:54:31PM +, Christopher Lameter wrote: > On Sat, 16 Jun 2018, john.hubb...@gmail.com wrote: > > > I've come up with what I claim is a simple, robust fix, but...I'm > > presuming to burn a struct page flag, and limit it to 64-bit arches, in > > order to get there.

Re: [PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-18 Thread Christoph Hellwig
On Sun, Jun 17, 2018 at 09:54:31PM +, Christopher Lameter wrote: > On Sat, 16 Jun 2018, john.hubb...@gmail.com wrote: > > > I've come up with what I claim is a simple, robust fix, but...I'm > > presuming to burn a struct page flag, and limit it to 64-bit arches, in > > order to get there.

Re: [PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-17 Thread John Hubbard
On 06/17/2018 02:54 PM, Christopher Lameter wrote: > On Sat, 16 Jun 2018, john.hubb...@gmail.com wrote: > >> I've come up with what I claim is a simple, robust fix, but...I'm >> presuming to burn a struct page flag, and limit it to 64-bit arches, in >> order to get there. Given that the problem

Re: [PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-17 Thread John Hubbard
On 06/17/2018 02:54 PM, Christopher Lameter wrote: > On Sat, 16 Jun 2018, john.hubb...@gmail.com wrote: > >> I've come up with what I claim is a simple, robust fix, but...I'm >> presuming to burn a struct page flag, and limit it to 64-bit arches, in >> order to get there. Given that the problem

Re: [PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-17 Thread Christopher Lameter
On Sat, 16 Jun 2018, john.hubb...@gmail.com wrote: > I've come up with what I claim is a simple, robust fix, but...I'm > presuming to burn a struct page flag, and limit it to 64-bit arches, in > order to get there. Given that the problem is old (Jason Gunthorpe noted > that RDMA has been living

Re: [PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-17 Thread Christopher Lameter
On Sat, 16 Jun 2018, john.hubb...@gmail.com wrote: > I've come up with what I claim is a simple, robust fix, but...I'm > presuming to burn a struct page flag, and limit it to 64-bit arches, in > order to get there. Given that the problem is old (Jason Gunthorpe noted > that RDMA has been living

[PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-16 Thread john . hubbard
From: John Hubbard Hi, I'm including people who have been talking about this. This is in one sense a medium-term work around, because there is a plan to talk about more extensive fixes at the upcoming Linux Plumbers Conference. I am seeing several customer bugs, though, and I really want to fix

[PATCH 0/2] mm: gup: don't unmap or drop filesystem buffers

2018-06-16 Thread john . hubbard
From: John Hubbard Hi, I'm including people who have been talking about this. This is in one sense a medium-term work around, because there is a plan to talk about more extensive fixes at the upcoming Linux Plumbers Conference. I am seeing several customer bugs, though, and I really want to fix