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| author | Conrad Meyer <cem@FreeBSD.org> | 2018-02-14 23:35:47 +0000 |
|---|---|---|
| committer | Conrad Meyer <cem@FreeBSD.org> | 2018-02-14 23:35:47 +0000 |
| commit | 5bd0149714c1ee467cda3558bf318aca0bb86898 (patch) | |
| tree | f184a25cdeb9ef05b99230f15b39f1e11fa95998 /sys/i386 | |
| parent | 8be8c75688e6b1941f4a9bbca512e5e4f4b877aa (diff) | |
| download | src-5bd0149714c1ee467cda3558bf318aca0bb86898.tar.gz src-5bd0149714c1ee467cda3558bf318aca0bb86898.zip | |
x86 pmap: Make memory mapped via pmap_qenter() non-executable
The idea is, the pmap_qenter() API is now defined to not produce executable
mappings. If you need executable mappings, use another API.
Add pg_nx flag in pmap_qenter on x86 to make kernel pages non-executable.
Other architectures that support execute-specific permissons on page table
entries should subsequently be updated to match.
Submitted by: Darrick Lew <darrick.freebsd AT gmail.com>
Reviewed by: markj
Discussed with: alc, jhb, kib
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D14062
Notes
Notes:
svn path=/head/; revision=329281
Diffstat (limited to 'sys/i386')
| -rw-r--r-- | sys/i386/i386/pmap.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c index 092c2f9909cc..c0895cabcc2e 100644 --- a/sys/i386/i386/pmap.c +++ b/sys/i386/i386/pmap.c @@ -1677,7 +1677,11 @@ pmap_qenter(vm_offset_t sva, vm_page_t *ma, int count) pa = VM_PAGE_TO_PHYS(m) | pmap_cache_bits(m->md.pat_mode, 0); if ((*pte & (PG_FRAME | PG_PTE_CACHE)) != pa) { oldpte |= *pte; +#if defined(PAE) || defined(PAE_TABLES) + pte_store(pte, pa | pgeflag | pg_nx | PG_RW | PG_V); +#else pte_store(pte, pa | pgeflag | PG_RW | PG_V); +#endif } pte++; } |