Re: [PATCH 0/4] arm64: wire up VM_FLUSH_RESET_PERMS

[Ard Biesheuvel <ard.biesheuvel@arm.com>]

On 5/28/19 12:04 PM, Will Deacon wrote:
> On Thu, May 23, 2019 at 11:22:52AM +0100, Ard Biesheuvel wrote:
>> Wire up the code introduced in v5.2 to manage the permissions
>> of executable vmalloc regions (and their linear aliases) more
>> strictly.
>>
>> One of the things that came up in the internal discussion is
>> whether non-x86 architectures have any benefit at all from the
>> lazy vunmap feature, and whether it would perhaps be better to
>> implement eager vunmap instead.
>>
>> Cc: Nadav Amit <namit@vmware.com>
>> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
>> Cc: Peter Zijlstra <peterz@infradead.org>
>> Cc: Andrew Morton <akpm@linux-foundation.org>
>> Cc: Will Deacon <will.deacon@arm.com>
>> Cc: Masami Hiramatsu <mhiramat@kernel.org>
>> Cc: James Morse <james.morse@arm.com>
>>
>> Ard Biesheuvel (4):
>>    arm64: module: create module allocations without exec permissions
>>    arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP
>>    arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages
>>    arm64: bpf: do not allocate executable memory
>>
>>   arch/arm64/Kconfig                  |  1 +
>>   arch/arm64/include/asm/cacheflush.h |  3 ++
>>   arch/arm64/kernel/module.c          |  4 +-
>>   arch/arm64/kernel/probes/kprobes.c  |  4 +-
>>   arch/arm64/mm/pageattr.c            | 48 ++++++++++++++++----
>>   arch/arm64/net/bpf_jit_comp.c       |  2 +-
>>   mm/vmalloc.c                        | 11 -----
>>   7 files changed, 50 insertions(+), 23 deletions(-)
> 
> Thanks, this all looks good to me. I can get pick this up for 5.2 if
> Rick's fixes [1] land soon enough.
> 

Note that you'll get a trivial conflict in the hunk against mm/vmalloc.c.