| Message ID | 20190330054121.27831-1-aneesh.kumar@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm: Fix modifying of page protection by insert_pfn_pmd() | expand |
On Sat 30-03-19 11:11:21, Aneesh Kumar K.V wrote: > With some architectures like ppc64, set_pmd_at() cannot cope with > a situation where there is already some (different) valid entry present. > > Use pmdp_set_access_flags() instead to modify the pfn which is built to > deal with modifying existing PMD entries. > > This is similar to > commit cae85cb8add3 ("mm/memory.c: fix modifying of page protection by insert_pfn()") > > We also do similar update w.r.t insert_pfn_pud eventhough ppc64 don't support > pud pfn entries now. > > CC: stable@vger.kernel.org > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Thanks for fixing this! The patch looks good to me. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > mm/huge_memory.c | 31 +++++++++++++++++++++++++++++++ > 1 file changed, 31 insertions(+) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 404acdcd0455..f7dca413c4b2 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -755,6 +755,20 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, > spinlock_t *ptl; > > ptl = pmd_lock(mm, pmd); > + if (!pmd_none(*pmd)) { > + if (write) { > + if (pmd_pfn(*pmd) != pfn_t_to_pfn(pfn)) { > + WARN_ON_ONCE(!is_huge_zero_pmd(*pmd)); > + goto out_unlock; > + } > + entry = pmd_mkyoung(*pmd); > + entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); > + if (pmdp_set_access_flags(vma, addr, pmd, entry, 1)) > + update_mmu_cache_pmd(vma, addr, pmd); > + } > + goto out_unlock; > + } > + > entry = pmd_mkhuge(pfn_t_pmd(pfn, prot)); > if (pfn_t_devmap(pfn)) > entry = pmd_mkdevmap(entry); > @@ -770,6 +784,7 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, > > set_pmd_at(mm, addr, pmd, entry); > update_mmu_cache_pmd(vma, addr, pmd); > +out_unlock: > spin_unlock(ptl); > } > > @@ -821,6 +836,20 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, > spinlock_t *ptl; > > ptl = pud_lock(mm, pud); > + if (!pud_none(*pud)) { > + if (write) { > + if (pud_pfn(*pud) != pfn_t_to_pfn(pfn)) { > + WARN_ON_ONCE(!is_huge_zero_pud(*pud)); > + goto out_unlock; > + } > + entry = pud_mkyoung(*pud); > + entry = maybe_pud_mkwrite(pud_mkdirty(entry), vma); > + if (pudp_set_access_flags(vma, addr, pud, entry, 1)) > + update_mmu_cache_pud(vma, addr, pud); > + } > + goto out_unlock; > + } > + > entry = pud_mkhuge(pfn_t_pud(pfn, prot)); > if (pfn_t_devmap(pfn)) > entry = pud_mkdevmap(entry); > @@ -830,6 +859,8 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, > } > set_pud_at(mm, addr, pud, entry); > update_mmu_cache_pud(vma, addr, pud); > + > +out_unlock: > spin_unlock(ptl); > } > > -- > 2.20.1 >
Hi,
[This is an automated email]
This commit has been processed because it contains a -stable tag.
The stable tag indicates that it's relevant for the following trees: all
The bot has tested the following trees: v5.0.5, v4.19.32, v4.14.109, v4.9.166, v4.4.177, v3.18.137.
v5.0.5: Build OK!
v4.19.32: Build OK!
v4.14.109: Build OK!
v4.9.166: Failed to apply! Possible dependencies:
82b0f8c39a38 ("mm: join struct fault_env and vm_fault")
953c66c2b22a ("mm: THP page cache support for ppc64")
a00cc7d9dd93 ("mm, x86: add support for PUD-sized transparent hugepages")
b5bc66b71310 ("mm: update mmu_gather range correctly")
fd60775aea80 ("mm, thp: avoid unlikely branches for split_huge_pmd")
v4.4.177: Failed to apply! Possible dependencies:
01871e59af5c ("mm, dax: fix livelock, allow dax pmd mappings to become writeable")
01c8f1c44b83 ("mm, dax, gpu: convert vm_insert_mixed to pfn_t")
0e749e54244e ("dax: increase granularity of dax_clear_blocks() operations")
34c0fd540e79 ("mm, dax, pmem: introduce pfn_t")
52db400fcd50 ("pmem, dax: clean up clear_pmem()")
6077776b5908 ("bpf: split HAVE_BPF_JIT into cBPF and eBPF variant")
a00cc7d9dd93 ("mm, x86: add support for PUD-sized transparent hugepages")
b2e0d1625e19 ("dax: fix lifetime of in-kernel dax mappings with dax_map_atomic()")
b329f95d70f3 ("ARM: 8479/2: add implementation for arm-smccc")
e37e43a497d5 ("x86/mm/64: Enable vmapped stacks (CONFIG_HAVE_ARCH_VMAP_STACK=y)")
f25748e3c34e ("mm, dax: convert vmf_insert_pfn_pmd() to pfn_t")
v3.18.137: Failed to apply! Possible dependencies:
047fc8a1f9a6 ("libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory")
2a3746984c98 ("x86: Use new cache mode type in track_pfn_remap() and track_pfn_insert()")
34c0fd540e79 ("mm, dax, pmem: introduce pfn_t")
4c1eaa2344fb ("drivers/block/pmem: Fix 32-bit build warning in pmem_alloc()")
5cad465d7fa6 ("mm: add vmf_insert_pfn_pmd()")
61031952f4c8 ("arch, x86: pmem api for ensuring durability of persistent memory updates")
62232e45f4a2 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices")
777783e0abae ("staging: android: binder: move to the "real" part of the kernel")
957e3facd147 ("gcov: enable GCOV_PROFILE_ALL from ARCH Kconfigs")
9e853f2313e5 ("drivers/block/pmem: Add a driver for persistent memory")
9f53f9fa4ad1 ("libnvdimm, pmem: add libnvdimm support to the pmem driver")
b94d5230d06e ("libnvdimm, nfit: initial libnvdimm infrastructure and NFIT support")
cb389b9c0e00 ("dax: drop size parameter to ->direct_access()")
dd22f551ac0a ("block: Change direct_access calling convention")
e2e05394e4a3 ("pmem, dax: have direct_access use __pmem annotation")
ec776ef6bbe1 ("x86/mm: Add support for the non-standard protected e820 type")
f0dc089ce217 ("libnvdimm: enable iostat")
f25748e3c34e ("mm, dax: convert vmf_insert_pfn_pmd() to pfn_t")
How should we proceed with this patch?
--
Thanks,
Sasha
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 404acdcd0455..f7dca413c4b2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -755,6 +755,20 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, spinlock_t *ptl; ptl = pmd_lock(mm, pmd); + if (!pmd_none(*pmd)) { + if (write) { + if (pmd_pfn(*pmd) != pfn_t_to_pfn(pfn)) { + WARN_ON_ONCE(!is_huge_zero_pmd(*pmd)); + goto out_unlock; + } + entry = pmd_mkyoung(*pmd); + entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); + if (pmdp_set_access_flags(vma, addr, pmd, entry, 1)) + update_mmu_cache_pmd(vma, addr, pmd); + } + goto out_unlock; + } + entry = pmd_mkhuge(pfn_t_pmd(pfn, prot)); if (pfn_t_devmap(pfn)) entry = pmd_mkdevmap(entry); @@ -770,6 +784,7 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, set_pmd_at(mm, addr, pmd, entry); update_mmu_cache_pmd(vma, addr, pmd); +out_unlock: spin_unlock(ptl); } @@ -821,6 +836,20 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, spinlock_t *ptl; ptl = pud_lock(mm, pud); + if (!pud_none(*pud)) { + if (write) { + if (pud_pfn(*pud) != pfn_t_to_pfn(pfn)) { + WARN_ON_ONCE(!is_huge_zero_pud(*pud)); + goto out_unlock; + } + entry = pud_mkyoung(*pud); + entry = maybe_pud_mkwrite(pud_mkdirty(entry), vma); + if (pudp_set_access_flags(vma, addr, pud, entry, 1)) + update_mmu_cache_pud(vma, addr, pud); + } + goto out_unlock; + } + entry = pud_mkhuge(pfn_t_pud(pfn, prot)); if (pfn_t_devmap(pfn)) entry = pud_mkdevmap(entry); @@ -830,6 +859,8 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, } set_pud_at(mm, addr, pud, entry); update_mmu_cache_pud(vma, addr, pud); + +out_unlock: spin_unlock(ptl); }
With some architectures like ppc64, set_pmd_at() cannot cope with a situation where there is already some (different) valid entry present. Use pmdp_set_access_flags() instead to modify the pfn which is built to deal with modifying existing PMD entries. This is similar to commit cae85cb8add3 ("mm/memory.c: fix modifying of page protection by insert_pfn()") We also do similar update w.r.t insert_pfn_pud eventhough ppc64 don't support pud pfn entries now. CC: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- mm/huge_memory.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+)