| Message ID | 20210115190451.3135416-5-axelrasmussen@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | userfaultfd: add minor fault handling | expand |
Hi Axel,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on arm64/for-next/core]
[also build test ERROR on powerpc/next s390/features tip/perf/core linus/master v5.11-rc3 next-20210115]
[cannot apply to hp-parisc/for-next hnaz-linux-mm/master ia64/next sparc-next/master sparc/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Axel-Rasmussen/userfaultfd-add-minor-fault-handling/20210116-030900
base: https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-next/core
config: microblaze-randconfig-r015-20210115 (attached as .config)
compiler: microblaze-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/71aa60d93cd66a7587771bf19dd4313f7bb078c0
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Axel-Rasmussen/userfaultfd-add-minor-fault-handling/20210116-030900
git checkout 71aa60d93cd66a7587771bf19dd4313f7bb078c0
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=microblaze
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
In file included from fs/userfaultfd.c:30:
fs/userfaultfd.c: In function 'hugetlb_unshare_all_pmds':
>> include/linux/hugetlb.h:967:49: error: implicit declaration of function 'flush_tlb_range'; did you mean 'flush_pmd_tlb_range'? [-Werror=implicit-function-declaration]
967 | #define flush_hugetlb_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end)
| ^~~~~~~~~~~~~~~
fs/userfaultfd.c:1224:2: note: in expansion of macro 'flush_hugetlb_tlb_range'
1224 | flush_hugetlb_tlb_range(vma, vma->vm_start, vma->vm_end);
| ^~~~~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +967 include/linux/hugetlb.h
97d3dcca13a550 Peter Xu 2021-01-15 961
868bfaed893a49 Peter Xu 2021-01-15 962 #ifndef __HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE
868bfaed893a49 Peter Xu 2021-01-15 963 /*
868bfaed893a49 Peter Xu 2021-01-15 964 * ARCHes with special requirements for evicting HUGETLB backing TLB entries can
868bfaed893a49 Peter Xu 2021-01-15 965 * implement this.
868bfaed893a49 Peter Xu 2021-01-15 966 */
868bfaed893a49 Peter Xu 2021-01-15 @967 #define flush_hugetlb_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end)
868bfaed893a49 Peter Xu 2021-01-15 968 #endif
868bfaed893a49 Peter Xu 2021-01-15 969
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 894cc28142e7..dfe5f7a21883 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -15,6 +15,7 @@ #include <linux/sched/signal.h> #include <linux/sched/mm.h> #include <linux/mm.h> +#include <linux/mmu_notifier.h> #include <linux/poll.h> #include <linux/slab.h> #include <linux/seq_file.h> @@ -1190,6 +1191,45 @@ static ssize_t userfaultfd_read(struct file *file, char __user *buf, } } +/* + * This function will unconditionally remove all the shared pmd pgtable entries + * within the specific vma for a hugetlbfs memory range. + */ +static void hugetlb_unshare_all_pmds(struct vm_area_struct *vma) +{ + struct hstate *h = hstate_vma(vma); + unsigned long sz = huge_page_size(h); + struct mm_struct *mm = vma->vm_mm; + struct mmu_notifier_range range; + unsigned long address; + spinlock_t *ptl; + pte_t *ptep; + + /* + * No need to call adjust_range_if_pmd_sharing_possible(), because + * we're going to operate on the whole vma + */ + mmu_notifier_range_init(&range, MMU_NOTIFY_HUGETLB_UNSHARE, + 0, vma, mm, vma->vm_start, vma->vm_end); + mmu_notifier_invalidate_range_start(&range); + i_mmap_lock_write(vma->vm_file->f_mapping); + for (address = vma->vm_start; address < vma->vm_end; address += sz) { + ptep = huge_pte_offset(mm, address, sz); + if (!ptep) + continue; + ptl = huge_pte_lock(h, mm, ptep); + huge_pmd_unshare(mm, vma, &address, ptep); + spin_unlock(ptl); + } + flush_hugetlb_tlb_range(vma, vma->vm_start, vma->vm_end); + i_mmap_unlock_write(vma->vm_file->f_mapping); + /* + * No need to call mmu_notifier_invalidate_range(), see + * Documentation/vm/mmu_notifier.rst. + */ + mmu_notifier_invalidate_range_end(&range); +} + static void __wake_userfault(struct userfaultfd_ctx *ctx, struct userfaultfd_wake_range *range) { @@ -1448,6 +1488,9 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, vma->vm_flags = new_flags; vma->vm_userfaultfd_ctx.ctx = ctx; + if (is_vm_hugetlb_page(vma) && uffd_disable_huge_pmd_share(vma)) + hugetlb_unshare_all_pmds(vma); + skip: prev = vma; start = vma->vm_end; diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h index b8200782dede..ff50c8528113 100644 --- a/include/linux/mmu_notifier.h +++ b/include/linux/mmu_notifier.h @@ -51,6 +51,7 @@ enum mmu_notifier_event { MMU_NOTIFY_SOFT_DIRTY, MMU_NOTIFY_RELEASE, MMU_NOTIFY_MIGRATE, + MMU_NOTIFY_HUGETLB_UNSHARE, }; #define MMU_NOTIFIER_RANGE_BLOCKABLE (1 << 0)