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authorDavid S. Miller <davem@davemloft.net>2016-06-10 21:52:24 +0300
committerDavid S. Miller <davem@davemloft.net>2016-06-10 21:52:24 +0300
commit1578b0a5e92825334760741e5c166b8873886f1b (patch)
treeac8299191f37990111f7d4b615601f4356e24fea /Documentation
parent3d5479e92087f6249231e26a2d7327e86a8d0dfc (diff)
parent698ea54dde6768d4a96080d0fb796cb3a4eadaf8 (diff)
downloadlinux-1578b0a5e92825334760741e5c166b8873886f1b.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: net/sched/act_police.c net/sched/sch_drr.c net/sched/sch_hfsc.c net/sched/sch_prio.c net/sched/sch_red.c net/sched/sch_tbf.c In net-next the drop methods of the packet schedulers got removed, so the bug fixes to them in 'net' are irrelevant. A packet action unload crash fix conflicts with the addition of the new firstuse timestamp. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation')
-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