Messages in this thread | | | Subject | Re: [patch 2/8] x86 PAT: set VM_PFNMAP flag in vm_insert_pfn | From | Benjamin Herrenschmidt <> | Date | Sat, 15 Nov 2008 18:38:27 +1100 |
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On Thu, 2008-11-13 at 00:23 +0100, Nick Piggin wrote: > You have to be careful of this, because it can be called with mmap_sem > held for read only. Hmm, I guess vm_insert_page is doing the same thing. > Probably mostly works because all other modifiers of vm_flags are holding > mmap_sem. > > However, in some cases, code can do vm_insert_pfn and vm_insert_page > (actually hmm, no vm_insert_mixed actually should cover most of those > cases). > > Still, I'd be much happier if we could make these into BUG_ON, and then > teach callers to set it in their .mmap routines.
Agreed. I don't think vm_insert_* is the right place to muck with that ..
Ben.
> > On Wed, Nov 12, 2008 at 01:26:49PM -0800, Venkatesh Pallipadi wrote: > > vm_insert_pfn() is not setting the VM_PFNMAP flag in vma. Fix that. > > > > Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> > > Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> > > > > --- > > mm/memory.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > Index: tip/mm/memory.c > > =================================================================== > > --- tip.orig/mm/memory.c 2008-11-06 09:44:56.000000000 -0800 > > +++ tip/mm/memory.c 2008-11-10 09:44:47.000000000 -0800 > > @@ -1444,6 +1444,8 @@ int vm_insert_pfn(struct vm_area_struct > > > > if (addr < vma->vm_start || addr >= vma->vm_end) > > return -EFAULT; > > + > > + vma->vm_flags |= VM_PFNMAP; > > return insert_pfn(vma, addr, pfn, vma->vm_page_prot); > > } > > EXPORT_SYMBOL(vm_insert_pfn); > > > > -- > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
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