The branch stable/15 has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=1d9c9fe8344969ea09b90105a0825e8105f4d9a9
commit 1d9c9fe8344969ea09b90105a0825e8105f4d9a9 Author: Konstantin Belousov <[email protected]> AuthorDate: 2026-08-19 02:27:46 +0000 Commit: Konstantin Belousov <[email protected]> CommitDate: 2026-08-26 00:44:10 +0000 shmfd: consistently return size in 512 byte blocks for fstat(2) st_blocks (cherry picked from commit 3a1bf59d195ced99c0f69774969d7090d21f6097) --- lib/libsys/stat.2 | 8 ++++++-- sys/kern/uipc_shm.c | 8 ++------ 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/lib/libsys/stat.2 b/lib/libsys/stat.2 index 7119fa797f0a..799f9bdbe1fc 100644 --- a/lib/libsys/stat.2 +++ b/lib/libsys/stat.2 @@ -271,10 +271,14 @@ be zero. .Pp For file descriptors referencing specific non-file objects, the field is type-specific. +.Pp For POSIX shared memory segments .Pq see Xr shm_open 2 , -the block size is equal to -the platform page size +the block size is 512 bytes. +For older versions of +.Fx +.Pq before 15.2 and 16.0 +the block size was equal to the platform page size .Pq Xr getpagesize 2 . .El .Pp diff --git a/sys/kern/uipc_shm.c b/sys/kern/uipc_shm.c index fa80eabc39a3..067a628fdab0 100644 --- a/sys/kern/uipc_shm.c +++ b/sys/kern/uipc_shm.c @@ -663,12 +663,8 @@ shm_stat(struct file *fp, struct stat *sb, struct ucred *active_cred) sb->st_dev = shm_dev_ino; sb->st_ino = shmfd->shm_ino; sb->st_nlink = shmfd->shm_object->ref_count; - if (shm_largepage(shmfd)) { - sb->st_blocks = shmfd->shm_object->size / - (pagesizes[shmfd->shm_lp_psind] >> PAGE_SHIFT); - } else { - sb->st_blocks = shmfd->shm_pages; - } + sb->st_blocks = ptoa(shm_largepage(shmfd) ? shmfd->shm_object->size : + shmfd->shm_pages) / DEV_BSIZE; return (0); }
