[Bug 260081] bhyve: capsicum preventing blockif hole-punching detection

From: <bugzilla-noreply_at_freebsd.org>
Date: Tue, 30 Nov 2021 21:51:04 UTC

--- Comment #5 from commit-hook@FreeBSD.org ---
A commit in branch main references this bug:


commit d8c1d7b6526c7063304cd1e938d12dec137454e2
Author:     Chuck Tuffli <chuck@FreeBSD.org>
AuthorDate: 2021-12-01 05:07:32 +0000
Commit:     Chuck Tuffli <chuck@FreeBSD.org>
CommitDate: 2021-12-01 05:49:34 +0000

    bhyve blockif: fix blockif_candelete with Capsicum

    NVMe conformance tests for the Format command failed if the
    backing-storage for the bhyve device was a file instead of a Zvol. The
    tests (and the specification) expect a Format to destroy all previously
    written data. The bhyve NVMe emulation implements this by trimming /
    deallocating all data from the backing-storage.

    The blockif_candelete() function indicated the file did not support
    deallocation (i.e. fpathconf(..., _PC_DEALLOC_PRESENT) returned FALSE)
    even though the kernel supported file hole punching. This occurs on
    builds with Capsicum enabled because blockif did not allow the
    fpathconf(2) right.

    Fix is to add CAP_FPATHCONF to the cap_rights_init(3) call.

    PR:             260081
    Reviewed by:    allanjude, markj, jhb
    MFC after:      1 week
    Differential Revision:  https://reviews.freebsd.org/D33203

 usr.sbin/bhyve/block_if.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

You are receiving this mail because:
You are the assignee for the bug.