| Message ID | be7c30cc-20fd-b5d6-83a2-366410753145@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | tmpfs: HUGEPAGE and MEM_LOCK fcntls and memfds | expand |
Hi Hugh,
I love your patch! Yet something to improve:
[auto build test ERROR on hch-configfs/for-next]
[also build test ERROR on linus/master v5.14-rc3 next-20210729]
[cannot apply to hnaz-linux-mm/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/Hugh-Dickins/tmpfs-HUGEPAGE-and-MEM_LOCK-fcntls-and-memfds/20210730-161413
base: git://git.infradead.org/users/hch/configfs.git for-next
config: riscv-randconfig-r022-20210730 (attached as .config)
compiler: riscv64-linux-gcc (GCC) 10.3.0
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/cad243cc46d563d62f2e0a20faa6571f7c6a692e
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Hugh-Dickins/tmpfs-HUGEPAGE-and-MEM_LOCK-fcntls-and-memfds/20210730-161413
git checkout cad243cc46d563d62f2e0a20faa6571f7c6a692e
# save the attached .config to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross O=build_dir ARCH=riscv SHELL=/bin/bash
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 >>):
riscv64-linux-ld: mm/shmem.o: in function `.L14':
>> shmem.c:(.text+0xec): undefined reference to `user_shm_lock'
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff --git a/include/uapi/linux/memfd.h b/include/uapi/linux/memfd.h index 8358a69e78cc..9113b5aa1763 100644 --- a/include/uapi/linux/memfd.h +++ b/include/uapi/linux/memfd.h @@ -9,6 +9,7 @@ #define MFD_ALLOW_SEALING 0x0002U #define MFD_HUGETLB 0x0004U /* Use hugetlbfs */ #define MFD_HUGEPAGE 0x0008U /* Use huge tmpfs */ +#define MFD_MEM_LOCK 0x0010U /* Memlock tmpfs */ /* * Huge page size encoding when MFD_HUGETLB is specified, and a huge page diff --git a/mm/memfd.c b/mm/memfd.c index 0d1a504d2fc9..e39f9eed55d2 100644 --- a/mm/memfd.c +++ b/mm/memfd.c @@ -248,7 +248,8 @@ long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long arg) #define MFD_ALL_FLAGS (MFD_CLOEXEC | \ MFD_ALLOW_SEALING | \ MFD_HUGETLB | \ - MFD_HUGEPAGE) + MFD_HUGEPAGE | \ + MFD_MEM_LOCK) SYSCALL_DEFINE2(memfd_create, const char __user *, uname, @@ -262,7 +263,7 @@ SYSCALL_DEFINE2(memfd_create, if (flags & MFD_HUGETLB) { /* Disallow huge tmpfs when choosing hugetlbfs */ - if (flags & MFD_HUGEPAGE) + if (flags & (MFD_HUGEPAGE | MFD_MEM_LOCK)) return -EINVAL; /* Allow huge page size encoding in flags. */ if (flags & ~(unsigned int)(MFD_ALL_FLAGS | @@ -314,6 +315,8 @@ SYSCALL_DEFINE2(memfd_create, if (flags & MFD_HUGEPAGE) vm_flags |= VM_HUGEPAGE; + if (flags & MFD_MEM_LOCK) + vm_flags |= VM_LOCKED; file = shmem_file_setup(name, 0, vm_flags); } diff --git a/mm/shmem.c b/mm/shmem.c index fa4a264453bf..a0a83e59ae07 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2395,7 +2395,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode spin_lock_init(&info->lock); atomic_set(&info->stop_eviction, 0); info->seals = F_SEAL_SEAL; - info->flags = flags & VM_NORESERVE; + info->flags = flags & (VM_NORESERVE | VM_LOCKED); if ((flags & VM_HUGEPAGE) && transparent_hugepage_allowed(sbinfo) && !test_bit(MMF_DISABLE_THP, ¤t->mm->flags)) @@ -4254,6 +4254,17 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, l inode->i_size = size; clear_nlink(inode); /* It is unlinked */ res = ERR_PTR(ramfs_nommu_expand_for_mapping(inode, size)); + if (!IS_ERR(res) && (flags & VM_LOCKED)) { + struct ucounts *ucounts = current_ucounts(); + /* + * Only memfd_create() may pass VM_LOCKED, and it passes + * size 0; but avoid that assumption in case it changes. + */ + if (user_shm_lock(size, ucounts, true)) + SHMEM_I(inode)->mlock_ucounts = ucounts; + else + res = ERR_PTR(-EPERM); + } if (!IS_ERR(res)) res = alloc_file_pseudo(inode, mnt, name, O_RDWR, &shmem_file_operations);
Now that the size of a memlocked file can be changed, memfd_create() can accept an MFD_MEM_LOCK flag to request memlocking, even though the initial size is of course 0. Signed-off-by: Hugh Dickins <hughd@google.com> --- include/uapi/linux/memfd.h | 1 + mm/memfd.c | 7 +++++-- mm/shmem.c | 13 ++++++++++++- 3 files changed, 18 insertions(+), 3 deletions(-)