Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-11 Thread Mikulas Patocka
On Wed, 9 Sep 2020, Darrick J. Wong wrote: > On Sat, Sep 05, 2020 at 01:02:33PM -0400, Mikulas Patocka wrote: > > > > > > > > I've written this program that tests it - you can integrate it into your > > testsuite. > > I don't get it. You're a filesystem maintainer too, which means you're >

Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-09 Thread Darrick J. Wong
On Sat, Sep 05, 2020 at 01:02:33PM -0400, Mikulas Patocka wrote: > > > On Sat, 5 Sep 2020, Darrick J. Wong wrote: > > > On Sat, Sep 05, 2020 at 08:13:02AM -0400, Mikulas Patocka wrote: > > > When running in a dax mode, if the user maps a page with MAP_PRIVATE and > > > PROT_WRITE, the xfs filesy

Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-07 Thread Jan Kara
On Sat 05-09-20 10:03:20, Linus Torvalds wrote: > On Sat, Sep 5, 2020 at 9:47 AM Linus Torvalds > wrote: > > > > So your patch is obviously correct, [..] > > Oh, and I had a xfs pull request in my inbox already, so rather than > expect Darrick to do another one just for this and have Jan do one f

Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-06 Thread Christoph Hellwig
> +static bool > +xfs_is_write_fault( > + struct vm_fault *vmf) > +{ > + return vmf->flags & FAULT_FLAG_WRITE && vmf->vma->vm_flags & VM_SHARED; > +} This function does not look xfs specific at all. Why isn't it it in fs.h? While we're at it the name sounds rather generic, and th

Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-05 Thread Linus Torvalds
On Sat, Sep 5, 2020 at 9:47 AM Linus Torvalds wrote: > > So your patch is obviously correct, [..] Oh, and I had a xfs pull request in my inbox already, so rather than expect Darrick to do another one just for this and have Jan do one for ext2, I just applied these two directly as "ObviouslyCorrec

Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-05 Thread Mikulas Patocka
On Sat, 5 Sep 2020, Darrick J. Wong wrote: > On Sat, Sep 05, 2020 at 08:13:02AM -0400, Mikulas Patocka wrote: > > When running in a dax mode, if the user maps a page with MAP_PRIVATE and > > PROT_WRITE, the xfs filesystem would incorrectly update ctime and mtime > > when the user hits a COW fau

Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-05 Thread Linus Torvalds
On Sat, Sep 5, 2020 at 5:13 AM Mikulas Patocka wrote: > > When running in a dax mode, if the user maps a page with MAP_PRIVATE and > PROT_WRITE, the xfs filesystem would incorrectly update ctime and mtime > when the user hits a COW fault. So your patch is obviously correct, but at the same time

Re: [PATCH 2/2] xfs: don't update mtime on COW faults

2020-09-05 Thread Darrick J. Wong
On Sat, Sep 05, 2020 at 08:13:02AM -0400, Mikulas Patocka wrote: > When running in a dax mode, if the user maps a page with MAP_PRIVATE and > PROT_WRITE, the xfs filesystem would incorrectly update ctime and mtime > when the user hits a COW fault. > > This breaks building of the Linux kernel. > Ho