Commit db431f6a authored by Gabriel de Perthuis's avatar Gabriel de Perthuis Committed by Aneesh Kumar K.V
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hw/9pfs: Be robust against paths without FS_IOC_GETVERSION 



9P optionally uses the FS_IOC_GETVERSION ioctl to get information about
a file's version (sometimes called generation number).

The code checks for supported filesystems at mount time, but some paths
may come from other mounted filesystems.

Change it to treat unsupported paths the same as unsupported
filesystems, returning 0 in both cases.

Note: ENOTTY is the error code for an unsupported ioctl.

This fix allows booting a linux kernel with the same / filesystem as the
host; otherwise the boot fails when mounting devtmpfs.

Signed-off-by: default avatarGabriel de Perthuis <g2p.code@gmail.com>
Reviewed-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
parent 0ceb092e

hw/9pfs/cofile.c

+4 −0
Original line number Diff line number Diff line
@@ -38,6 +38,10 @@ int v9fs_co_st_gen(V9fsPDU *pdu, V9fsPath *path, mode_t st_mode, 
            });

        v9fs_path_unlock(s);

    }

    /* The ioctl may not be supported depending on the path */

    if (err == -ENOTTY) {

        err = 0;

    }

    return err;

}