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-rw-r--r--Documentation/DocBook/device-drivers.tmpl36
-rw-r--r--Documentation/arm64/silicon-errata.txt1
-rw-r--r--Documentation/devicetree/bindings/display/imx/ldb.txt1
-rw-r--r--Documentation/filesystems/devpts.txt145
-rw-r--r--Documentation/kdump/gdbmacros.txt93
-rw-r--r--Documentation/security/keys.txt5
6 files changed, 135 insertions, 146 deletions
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index de79efdad46c..8c68768ebee5 100644
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -128,16 +128,44 @@ X!Edrivers/base/interface.c
!Edrivers/base/platform.c
!Edrivers/base/bus.c
</sect1>
- <sect1><title>Device Drivers DMA Management</title>
+ <sect1>
+ <title>Buffer Sharing and Synchronization</title>
+ <para>
+ The dma-buf subsystem provides the framework for sharing buffers
+ for hardware (DMA) access across multiple device drivers and
+ subsystems, and for synchronizing asynchronous hardware access.
+ </para>
+ <para>
+ This is used, for example, by drm "prime" multi-GPU support, but
+ is of course not limited to GPU use cases.
+ </para>
+ <para>
+ The three main components of this are: (1) dma-buf, representing
+ a sg_table and exposed to userspace as a file descriptor to allow
+ passing between devices, (2) fence, which provides a mechanism
+ to signal when one device as finished access, and (3) reservation,
+ which manages the shared or exclusive fence(s) associated with
+ the buffer.
+ </para>
+ <sect2><title>dma-buf</title>
!Edrivers/dma-buf/dma-buf.c
+!Iinclude/linux/dma-buf.h
+ </sect2>
+ <sect2><title>reservation</title>
+!Pdrivers/dma-buf/reservation.c Reservation Object Overview
+!Edrivers/dma-buf/reservation.c
+!Iinclude/linux/reservation.h
+ </sect2>
+ <sect2><title>fence</title>
!Edrivers/dma-buf/fence.c
-!Edrivers/dma-buf/seqno-fence.c
!Iinclude/linux/fence.h
+!Edrivers/dma-buf/seqno-fence.c
!Iinclude/linux/seqno-fence.h
-!Edrivers/dma-buf/reservation.c
-!Iinclude/linux/reservation.h
!Edrivers/dma-buf/sync_file.c
!Iinclude/linux/sync_file.h
+ </sect2>
+ </sect1>
+ <sect1><title>Device Drivers DMA Management</title>
!Edrivers/base/dma-coherent.c
!Edrivers/base/dma-mapping.c
</sect1>
diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt
index c6938e50e71f..4da60b463995 100644
--- a/Documentation/arm64/silicon-errata.txt
+++ b/Documentation/arm64/silicon-errata.txt
@@ -56,6 +56,7 @@ stable kernels.
| ARM | MMU-500 | #841119,#826419 | N/A |
| | | | |
| Cavium | ThunderX ITS | #22375, #24313 | CAVIUM_ERRATUM_22375 |
+| Cavium | ThunderX ITS | #23144 | CAVIUM_ERRATUM_23144 |
| Cavium | ThunderX GICv3 | #23154 | CAVIUM_ERRATUM_23154 |
| Cavium | ThunderX Core | #27456 | CAVIUM_ERRATUM_27456 |
| Cavium | ThunderX SMMUv2 | #27704 | N/A |
diff --git a/Documentation/devicetree/bindings/display/imx/ldb.txt b/Documentation/devicetree/bindings/display/imx/ldb.txt
index 0a175d991b52..a407462c885e 100644
--- a/Documentation/devicetree/bindings/display/imx/ldb.txt
+++ b/Documentation/devicetree/bindings/display/imx/ldb.txt
@@ -62,6 +62,7 @@ Required properties:
display-timings are used instead.
Optional properties (required if display-timings are used):
+ - ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
- display-timings : A node that describes the display timings as defined in
Documentation/devicetree/bindings/display/display-timing.txt.
- fsl,data-mapping : should be "spwg" or "jeida"
diff --git a/Documentation/filesystems/devpts.txt b/Documentation/filesystems/devpts.txt
index 30d2fcb32f72..9f94fe276dea 100644
--- a/Documentation/filesystems/devpts.txt
+++ b/Documentation/filesystems/devpts.txt
@@ -1,141 +1,26 @@
+Each mount of the devpts filesystem is now distinct such that ptys
+and their indicies allocated in one mount are independent from ptys
+and their indicies in all other mounts.
-To support containers, we now allow multiple instances of devpts filesystem,
-such that indices of ptys allocated in one instance are independent of indices
-allocated in other instances of devpts.
+All mounts of the devpts filesystem now create a /dev/pts/ptmx node
+with permissions 0000.
-To preserve backward compatibility, this support for multiple instances is
-enabled only if:
+To retain backwards compatibility the a ptmx device node (aka any node
+created with "mknod name c 5 2") when opened will look for an instance
+of devpts under the name "pts" in the same directory as the ptmx device
+node.
- - CONFIG_DEVPTS_MULTIPLE_INSTANCES=y, and
- - '-o newinstance' mount option is specified while mounting devpts
-
-IOW, devpts now supports both single-instance and multi-instance semantics.
-
-If CONFIG_DEVPTS_MULTIPLE_INSTANCES=n, there is no change in behavior and
-this referred to as the "legacy" mode. In this mode, the new mount options
-(-o newinstance and -o ptmxmode) will be ignored with a 'bogus option' message
-on console.
-
-If CONFIG_DEVPTS_MULTIPLE_INSTANCES=y and devpts is mounted without the
-'newinstance' option (as in current start-up scripts) the new mount binds
-to the initial kernel mount of devpts. This mode is referred to as the
-'single-instance' mode and the current, single-instance semantics are
-preserved, i.e PTYs are common across the system.
-
-The only difference between this single-instance mode and the legacy mode
-is the presence of new, '/dev/pts/ptmx' node with permissions 0000, which
-can safely be ignored.
-
-If CONFIG_DEVPTS_MULTIPLE_INSTANCES=y and 'newinstance' option is specified,
-the mount is considered to be in the multi-instance mode and a new instance
-of the devpts fs is created. Any ptys created in this instance are independent
-of ptys in other instances of devpts. Like in the single-instance mode, the
-/dev/pts/ptmx node is present. To effectively use the multi-instance mode,
-open of /dev/ptmx must be a redirected to '/dev/pts/ptmx' using a symlink or
-bind-mount.
-
-Eg: A container startup script could do the following:
-
- $ chmod 0666 /dev/pts/ptmx
- $ rm /dev/ptmx
- $ ln -s pts/ptmx /dev/ptmx
- $ ns_exec -cm /bin/bash
-
- # We are now in new container
-
- $ umount /dev/pts
- $ mount -t devpts -o newinstance lxcpts /dev/pts
- $ sshd -p 1234
-
-where 'ns_exec -cm /bin/bash' calls clone() with CLONE_NEWNS flag and execs
-/bin/bash in the child process. A pty created by the sshd is not visible in
-the original mount of /dev/pts.
+As an option instead of placing a /dev/ptmx device node at /dev/ptmx
+it is possible to place a symlink to /dev/pts/ptmx at /dev/ptmx or
+to bind mount /dev/ptx/ptmx to /dev/ptmx. If you opt for using
+the devpts filesystem in this manner devpts should be mounted with
+the ptmxmode=0666, or chmod 0666 /dev/pts/ptmx should be called.
Total count of pty pairs in all instances is limited by sysctls:
kernel.pty.max = 4096 - global limit
-kernel.pty.reserve = 1024 - reserve for initial instance
+kernel.pty.reserve = 1024 - reserved for filesystems mounted from the initial mount namespace
kernel.pty.nr - current count of ptys
Per-instance limit could be set by adding mount option "max=<count>".
This feature was added in kernel 3.4 together with sysctl kernel.pty.reserve.
In kernels older than 3.4 sysctl kernel.pty.max works as per-instance limit.
-
-User-space changes
-------------------
-
-In multi-instance mode (i.e '-o newinstance' mount option is specified at least
-once), following user-space issues should be noted.
-
-1. If -o newinstance mount option is never used, /dev/pts/ptmx can be ignored
- and no change is needed to system-startup scripts.
-
-2. To effectively use multi-instance mode (i.e -o newinstance is specified)
- administrators or startup scripts should "redirect" open of /dev/ptmx to
- /dev/pts/ptmx using either a bind mount or symlink.
-
- $ mount -t devpts -o newinstance devpts /dev/pts
-
- followed by either
-
- $ rm /dev/ptmx
- $ ln -s pts/ptmx /dev/ptmx
- $ chmod 666 /dev/pts/ptmx
- or
- $ mount -o bind /dev/pts/ptmx /dev/ptmx
-
-3. The '/dev/ptmx -> pts/ptmx' symlink is the preferred method since it
- enables better error-reporting and treats both single-instance and
- multi-instance mounts similarly.
-
- But this method requires that system-startup scripts set the mode of
- /dev/pts/ptmx correctly (default mode is 0000). The scripts can set the
- mode by, either
-
- - adding ptmxmode mount option to devpts entry in /etc/fstab, or
- - using 'chmod 0666 /dev/pts/ptmx'
-
-4. If multi-instance mode mount is needed for containers, but the system
- startup scripts have not yet been updated, container-startup scripts
- should bind mount /dev/ptmx to /dev/pts/ptmx to avoid breaking single-
- instance mounts.
-
- Or, in general, container-startup scripts should use:
-
- mount -t devpts -o newinstance -o ptmxmode=0666 devpts /dev/pts
- if [ ! -L /dev/ptmx ]; then
- mount -o bind /dev/pts/ptmx /dev/ptmx
- fi
-
- When all devpts mounts are multi-instance, /dev/ptmx can permanently be
- a symlink to pts/ptmx and the bind mount can be ignored.
-
-5. A multi-instance mount that is not accompanied by the /dev/ptmx to
- /dev/pts/ptmx redirection would result in an unusable/unreachable pty.
-
- mount -t devpts -o newinstance lxcpts /dev/pts
-
- immediately followed by:
-
- open("/dev/ptmx")
-
- would create a pty, say /dev/pts/7, in the initial kernel mount.
- But /dev/pts/7 would be invisible in the new mount.
-
-6. The permissions for /dev/pts/ptmx node should be specified when mounting
- /dev/pts, using the '-o ptmxmode=%o' mount option (default is 0000).
-
- mount -t devpts -o newinstance -o ptmxmode=0644 devpts /dev/pts
-
- The permissions can be later be changed as usual with 'chmod'.
-
- chmod 666 /dev/pts/ptmx
-
-7. A mount of devpts without the 'newinstance' option results in binding to
- initial kernel mount. This behavior while preserving legacy semantics,
- does not provide strict isolation in a container environment. i.e by
- mounting devpts without the 'newinstance' option, a container could
- get visibility into the 'host' or root container's devpts.
-
- To workaround this and have strict isolation, all mounts of devpts,
- including the mount in the root container, should use the newinstance
- option.
diff --git a/Documentation/kdump/gdbmacros.txt b/Documentation/kdump/gdbmacros.txt
index 35f6a982a0d5..220d0a80ca2c 100644
--- a/Documentation/kdump/gdbmacros.txt
+++ b/Documentation/kdump/gdbmacros.txt
@@ -170,21 +170,92 @@ document trapinfo
address the kernel panicked.
end
+define dump_log_idx
+ set $idx = $arg0
+ if ($argc > 1)
+ set $prev_flags = $arg1
+ else
+ set $prev_flags = 0
+ end
+ set $msg = ((struct printk_log *) (log_buf + $idx))
+ set $prefix = 1
+ set $newline = 1
+ set $log = log_buf + $idx + sizeof(*$msg)
-define dmesg
- set $i = 0
- set $end_idx = (log_end - 1) & (log_buf_len - 1)
+ # prev & LOG_CONT && !(msg->flags & LOG_PREIX)
+ if (($prev_flags & 8) && !($msg->flags & 4))
+ set $prefix = 0
+ end
+
+ # msg->flags & LOG_CONT
+ if ($msg->flags & 8)
+ # (prev & LOG_CONT && !(prev & LOG_NEWLINE))
+ if (($prev_flags & 8) && !($prev_flags & 2))
+ set $prefix = 0
+ end
+ # (!(msg->flags & LOG_NEWLINE))
+ if (!($msg->flags & 2))
+ set $newline = 0
+ end
+ end
+
+ if ($prefix)
+ printf "[%5lu.%06lu] ", $msg->ts_nsec / 1000000000, $msg->ts_nsec % 1000000000
+ end
+ if ($msg->text_len != 0)
+ eval "printf \"%%%d.%ds\", $log", $msg->text_len, $msg->text_len
+ end
+ if ($newline)
+ printf "\n"
+ end
+ if ($msg->dict_len > 0)
+ set $dict = $log + $msg->text_len
+ set $idx = 0
+ set $line = 1
+ while ($idx < $msg->dict_len)
+ if ($line)
+ printf " "
+ set $line = 0
+ end
+ set $c = $dict[$idx]
+ if ($c == '\0')
+ printf "\n"
+ set $line = 1
+ else
+ if ($c < ' ' || $c >= 127 || $c == '\\')
+ printf "\\x%02x", $c
+ else
+ printf "%c", $c
+ end
+ end
+ set $idx = $idx + 1
+ end
+ printf "\n"
+ end
+end
+document dump_log_idx
+ Dump a single log given its index in the log buffer. The first
+ parameter is the index into log_buf, the second is optional and
+ specified the previous log buffer's flags, used for properly
+ formatting continued lines.
+end
- while ($i < logged_chars)
- set $idx = (log_end - 1 - logged_chars + $i) & (log_buf_len - 1)
+define dmesg
+ set $i = log_first_idx
+ set $end_idx = log_first_idx
+ set $prev_flags = 0
- if ($idx + 100 <= $end_idx) || \
- ($end_idx <= $idx && $idx + 100 < log_buf_len)
- printf "%.100s", &log_buf[$idx]
- set $i = $i + 100
+ while (1)
+ set $msg = ((struct printk_log *) (log_buf + $i))
+ if ($msg->len == 0)
+ set $i = 0
else
- printf "%c", log_buf[$idx]
- set $i = $i + 1
+ dump_log_idx $i $prev_flags
+ set $i = $i + $msg->len
+ set $prev_flags = $msg->flags
+ end
+ if ($i == $end_idx)
+ loop_break
end
end
end
diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt
index 20d05719bceb..3849814bfe6d 100644
--- a/Documentation/security/keys.txt
+++ b/Documentation/security/keys.txt
@@ -826,7 +826,8 @@ The keyctl syscall functions are:
(*) Compute a Diffie-Hellman shared secret or public key
long keyctl(KEYCTL_DH_COMPUTE, struct keyctl_dh_params *params,
- char *buffer, size_t buflen);
+ char *buffer, size_t buflen,
+ void *reserved);
The params struct contains serial numbers for three keys:
@@ -843,6 +844,8 @@ The keyctl syscall functions are:
public key. If the base is the remote public key, the result is
the shared secret.
+ The reserved argument must be set to NULL.
+
The buffer length must be at least the length of the prime, or zero.
If the buffer length is nonzero, the length of the result is
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-22 06:34:27 +0300