On 10/30/24 5:39 AM, Catalin Marinas wrote:
On Wed, Oct 30, 2024 at 11:53:06AM +0000, Lorenzo Stoakes wrote:
On Wed, Oct 30, 2024 at 12:09:43PM +0100, Vlastimil Babka wrote:
On 10/30/24 11:58, Catalin Marinas wrote:
On Wed, Oct 30, 2024 at 10:18:27AM +0100, Vlastimil Babka wrote:
On 10/29/24 19:11, Lorenzo Stoakes wrote:
--- a/arch/arm64/include/asm/mman.h
+++ b/arch/arm64/include/asm/mman.h
@@ -6,6 +6,8 @@
#ifndef BUILD_VDSO
#include <linux/compiler.h>
+#include <linux/fs.h>
+#include <linux/shmem_fs.h>
#include <linux/types.h>
static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
@@ -31,19 +33,21 @@ static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
}
#define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
-static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags)
+static inline unsigned long arch_calc_vm_flag_bits(struct file *file,
+ unsigned long flags)
{
/*
* Only allow MTE on anonymous mappings as these are guaranteed to be
* backed by tags-capable memory. The vm_flags may be overridden by a
* filesystem supporting MTE (RAM-based).
We should also eventually remove the last sentence or even replace it with
its negation, or somebody might try reintroducing the pattern that won't
work anymore (wasn't there such a hugetlbfs thing in -next?).
I agree, we should update this comment as well though as a fix this
patch is fine for now.
There is indeed a hugetlbfs change in -next adding VM_MTE_ALLOWED. It
should still work after the above change but we'd need to move it over
I guess it will work after the above change, but not after 5/5?
here (and fix the comment at the same time). We'll probably do it around
-rc1 or maybe earlier once this fix hits mainline.
I assume this will hopefully go to rc7.
To be clear - this is a CRITICAL fix that MUST land for 6.12. I'd be inclined to
try to get it to an earlier rc-.
Ah, good point. So after this series is merged at rc6/rc7, the new
MTE+hugetlbfs in -next won't work. Not an issue, it can be sorted out
later.
I don't think we have
an equivalent of shmem_file() for hugetlbfs, we'll need to figure
something out.
I've found is_file_hugepages(), could work? And while adding the hugetlbfs
change here, the comment could be adjusted too, right?
Right but the MAP_HUGETLB should work to? Can we save such changes that
alter any kind of existing behaviour to later series?
As this is going to be backported (by me...!) and I don't want to risk
inadvertant changes.
MAP_HUGETLB and is_file_hugepages() fixes can go in after 6.13-rc1. This
series is fine as is, we wouldn't backport any MAP_HUGETLB changes
anyway since the flag check wasn't the only issue that needed addressing
for hugetlb MTE mappings.
I agree. The fix looks trivial.
