From dd05add7b2b6004c5fa3a1f276f56d8668f86b65 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Sat, 26 Sep 2026 19:20:30 -0300 Subject: netfs: zero the tail of a short DIO/unbuffered read The buffered read collector zero-fills the tail of a short read that stops below the inode's i_size (netfs_clear_unread()), so a read that races an extending write still returns the expected number of bytes. The non-buffered collector path does no such thing: it just records how much was transferred. Add the same zero-fill for the non-buffered case, gated on NETFS_SREQ_CLEAR_TAIL: a subreq's source sets that flag when a short result from it is known to be safe to treat as a hole, as opposed to NETFS_SREQ_HIT_EOF, which means the read genuinely ran off the end of the file and should be reported short as-is. Only CLEAR_TAIL should zero-fill here; a real EOF must stay a real short read. No source currently sets CLEAR_TAIL on an unbuffered/DIO subrequest, so this is inert on its own -- a following change teaches cifs to set it in the one case that needs it. Fixes: e2d46f2ec332 ("netfs: Change the read result collector to only use one work item") Reviewed-by: David Howells Reviewed-by: Namjae Jeon Signed-off-by: Paulo Alcantara Cc: Christian Brauner Cc: Matthew Wilcox Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Bharath SM Cc: stable@vger.kernel.org --- Documentation/admin-guide/mono.rst | 70 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 Documentation/admin-guide/mono.rst (limited to 'Documentation/admin-guide/mono.rst') diff --git a/Documentation/admin-guide/mono.rst b/Documentation/admin-guide/mono.rst new file mode 100644 index 000000000..c6dab5680 --- /dev/null +++ b/Documentation/admin-guide/mono.rst @@ -0,0 +1,70 @@ +Mono(tm) Binary Kernel Support for Linux +----------------------------------------- + +To configure Linux to automatically execute Mono-based .NET binaries +(in the form of .exe files) without the need to use the mono CLR +wrapper, you can use the BINFMT_MISC kernel support. + +This will allow you to execute Mono-based .NET binaries just like any +other program after you have done the following: + +1) You MUST FIRST install the Mono CLR support, either by downloading + a binary package, a source tarball or by installing from Git. Binary + packages for several distributions can be found at: + + https://www.mono-project.com/download/ + + Instructions for compiling Mono can be found at: + + https://www.mono-project.com/docs/compiling-mono/linux/ + + Once the Mono CLR support has been installed, just check that + ``/usr/bin/mono`` (which could be located elsewhere, for example + ``/usr/local/bin/mono``) is working. + +2) You have to compile BINFMT_MISC either as a module or into + the kernel (``CONFIG_BINFMT_MISC``) and set it up properly. + If you choose to compile it as a module, you will have + to insert it manually with modprobe/insmod, as kmod + cannot be easily supported with binfmt_misc. + Read the file ``binfmt_misc.txt`` in this directory to know + more about the configuration process. + +3) Add the following entries to ``/etc/rc.local`` or similar script + to be run at system startup: + + .. code-block:: sh + + # Insert BINFMT_MISC module into the kernel + if [ ! -e /proc/sys/fs/binfmt_misc/register ]; then + /sbin/modprobe binfmt_misc + # Some distributions, like Fedora Core, perform + # the following command automatically when the + # binfmt_misc module is loaded into the kernel + # or during normal boot up (systemd-based systems). + # Thus, it is possible that the following line + # is not needed at all. + mount -t binfmt_misc none /proc/sys/fs/binfmt_misc + fi + + # Register support for .NET CLR binaries + if [ -e /proc/sys/fs/binfmt_misc/register ]; then + # Replace /usr/bin/mono with the correct pathname to + # the Mono CLR runtime (usually /usr/local/bin/mono + # when compiling from sources or CVS). + echo ':CLR:M::MZ::/usr/bin/mono:' > /proc/sys/fs/binfmt_misc/register + else + echo "No binfmt_misc support" + exit 1 + fi + +4) Check that ``.exe`` binaries can be ran without the need of a + wrapper script, simply by launching the ``.exe`` file directly + from a command prompt, for example:: + + /usr/bin/xsd.exe + + .. note:: + + If this fails with a permission denied error, check + that the ``.exe`` file has execute permissions. -- cgit v1.3.1