linux-toradex.git/tools/testing/vma/tests/merge.c, branch master

mm/vma: convert vma_modify_flags[_uffd]() to use vma_flags_t

2026-04-05T20:53:41+00:00

Update the vma_modify_flags() and vma_modify_flags_uffd() functions to
accept a vma_flags_t parameter rather than a vm_flags_t one, and propagate
the changes as needed to implement this change.

Also add vma_flags_reset_once() in replacement of vm_flags_reset_once(). We
still need to be careful here because we need to avoid tearing, so maintain
the assumption that the first system word set of flags are the only ones
that require protection from tearing, and retain this functionality.

We can copy the remainder of VMA flags above 64 bits normally. But
hopefully by the time that happens, we will have replaced the logic that
requires these WRITE_ONCE()'s with something else.

We also replace instances of vm_flags_reset() with a simple write of VMA
flags. We are no longer perform a number of checks, most notable of all the
VMA flags asserts becase:

1. We might be operating on a VMA that is not yet added to the tree.

2. We might be operating on a VMA that is now detached.

3. Really in all but core code, you should be using vma_desc_xxx().

4. Other VMA fields are manipulated with no such checks.

5. It'd be egregious to have to add variants of flag functions just to
   account for cases such as the above, especially when we don't do so for
   other VMA fields. Drivers are the problematic cases and why it was
   especially important (and also for debug as VMA locks were introduced),
   the mmap_prepare work is solving this generally.

Additionally, we can fairly safely assume by this point the soft dirty
flags are being set correctly, so it's reasonable to drop this also.

Finally, update the VMA tests to reflect this.

Link: https://lkml.kernel.org/r/51afbb2b8c3681003cc7926647e37335d793836e.1774034900.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) 
Acked-by: Vlastimil Babka (SUSE) 
Cc: Albert Ou 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Al Viro 
Cc: Anton Ivanov 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: Chengming Zhou 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Dinh Nguyen 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Johannes Berg 
Cc: Kees Cook 
Cc: Liam Howlett 
Cc: Madhavan Srinivasan 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Nicholas Piggin 
Cc: Ondrej Mosnacek 
Cc: Palmer Dabbelt 
Cc: Paul Moore 
Cc: Pedro Falcato 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Stephen Smalley 
Cc: Suren Baghdasaryan 
Cc: Sven Schnelle 
Cc: Thomas Bogendoerfer 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: WANG Xuerui 
Cc: Will Deacon 
Cc: xu xin 
Signed-off-by: Andrew Morton

mm: convert do_brk_flags() to use vma_flags_t

2026-04-05T20:53:40+00:00

In order to be able to do this, we need to change VM_DATA_DEFAULT_FLAGS
and friends and update the architecture-specific definitions also.

We then have to update some KSM logic to handle VMA flags, and introduce
VMA_STACK_FLAGS to define the vma_flags_t equivalent of VM_STACK_FLAGS.

We also introduce two helper functions for use during the time we are
converting legacy flags to vma_flags_t values - vma_flags_to_legacy() and
legacy_to_vma_flags().

This enables us to iteratively make changes to break these changes up into
separate parts.

We use these explicitly here to keep VM_STACK_FLAGS around for certain
users which need to maintain the legacy vm_flags_t values for the time
being.

We are no longer able to rely on the simple VM_xxx being set to zero if
the feature is not enabled, so in the case of VM_DROPPABLE we introduce
VMA_DROPPABLE as the vma_flags_t equivalent, which is set to
EMPTY_VMA_FLAGS if the droppable flag is not available.

While we're here, we make the description of do_brk_flags() into a kdoc
comment, as it almost was already.

We use vma_flags_to_legacy() to not need to update the vm_get_page_prot()
logic as this time.

Note that in create_init_stack_vma() we have to replace the BUILD_BUG_ON()
with a VM_WARN_ON_ONCE() as the tested values are no longer build time
available.

We also update mprotect_fixup() to use VMA flags where possible, though we
have to live with a little duplication between vm_flags_t and vma_flags_t
values for the time being until further conversions are made.

While we're here, update VM_SPECIAL to be defined in terms of
VMA_SPECIAL_FLAGS now we have vma_flags_to_legacy().

Finally, we update the VMA tests to reflect these changes.

Link: https://lkml.kernel.org/r/d02e3e45d9a33d7904b149f5604904089fd640ae.1774034900.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) 
Acked-by: Paul Moore 	[SELinux]
Acked-by: Vlastimil Babka (SUSE) 
Cc: Albert Ou 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Al Viro 
Cc: Anton Ivanov 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: Chengming Zhou 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Dinh Nguyen 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Johannes Berg 
Cc: Kees Cook 
Cc: Liam Howlett 
Cc: Madhavan Srinivasan 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Nicholas Piggin 
Cc: Ondrej Mosnacek 
Cc: Palmer Dabbelt 
Cc: Pedro Falcato 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Stephen Smalley 
Cc: Suren Baghdasaryan 
Cc: Sven Schnelle 
Cc: Thomas Bogendoerfer 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: WANG Xuerui 
Cc: Will Deacon 
Cc: xu xin 
Signed-off-by: Andrew Morton

tools/testing/vma: convert bulk of test code to vma_flags_t

2026-04-05T20:53:38+00:00

Convert the test code to utilise vma_flags_t as opposed to the deprecate
vm_flags_t as much as possible.

As part of this change, add VMA_STICKY_FLAGS and VMA_SPECIAL_FLAGS as
early versions of what these defines will look like in the kernel logic
once this logic is implemented.

Link: https://lkml.kernel.org/r/df90efe29300bd899989f695be4ae3adc901a828.1774034900.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) 
Cc: Albert Ou 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Al Viro 
Cc: Anton Ivanov 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: Chengming Zhou 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Dinh Nguyen 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Johannes Berg 
Cc: Kees Cook 
Cc: Liam Howlett 
Cc: Madhavan Srinivasan 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Nicholas Piggin 
Cc: Ondrej Mosnacek 
Cc: Palmer Dabbelt 
Cc: Paul Moore 
Cc: Pedro Falcato 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Stephen Smalley 
Cc: Suren Baghdasaryan 
Cc: Sven Schnelle 
Cc: Thomas Bogendoerfer 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Vlastimil Babka (SUSE) 
Cc: WANG Xuerui 
Cc: Will Deacon 
Cc: xu xin 
Signed-off-by: Andrew Morton

tools/testing/vma: separate VMA userland tests into separate files

2026-02-12T23:42:59+00:00

So far the userland VMA tests have been established as a rough expression
of what's been possible.

Adapt it into a more usable form by separating out tests and shared
helper functions.

Since we test functions that are declared statically in mm/vma.c, we make
use of the trick of #include'ing kernel C files directly.

In order for the tests to continue to function, we must therefore also
this way into the tests/ directory.

We try to keep as much shared logic actually modularised into a separate
compilation unit in shared.c, however the merge_existing() and
attach_vma() helpers rely on statically declared mm/vma.c functions so
these must be declared in main.c.

Link: https://lkml.kernel.org/r/a0455ccfe4fdcd1c962c64f76304f612e5662a4e.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes 
Reviewed-by: Liam R. Howlett 
Cc: Baolin Wang 
Cc: Barry Song 
Cc: David Hildenbrand 
Cc: Dev Jain 
Cc: Jason Gunthorpe 
Cc: Suren Baghdasaryan 
Cc: Vlastimil Babka 
Cc: Zi Yan 
Cc: Damien Le Moal 
Cc: "Darrick J. Wong" 
Cc: Jarkko Sakkinen 
Cc: Yury Norov 
Cc: Chris Mason 
Cc: Pedro Falcato 
Signed-off-by: Andrew Morton