path: root/Documentation
diff options
Diffstat (limited to 'Documentation')
4 files changed, 49 insertions, 8 deletions
diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst
index 8ebe46b1af39..5dfcc4592b23 100644
--- a/Documentation/core-api/printk-formats.rst
+++ b/Documentation/core-api/printk-formats.rst
@@ -112,6 +112,20 @@ used when printing stack backtraces. The specifier takes into
consideration the effect of compiler optimisations which may occur
when tail-calls are used and marked with the noreturn GCC attribute.
+Probed Pointers from BPF / tracing
+ %pks kernel string
+ %pus user string
+The ``k`` and ``u`` specifiers are used for printing prior probed memory from
+either kernel memory (k) or user memory (u). The subsequent ``s`` specifier
+results in printing a string. For direct use in regular vsnprintf() the (k)
+and (u) annotation is ignored, however, when used out of BPF's bpf_trace_printk(),
+for example, it reads the memory it is pointing to without faulting.
Kernel Pointers
diff --git a/Documentation/devicetree/bindings/dma/fsl-edma.txt b/Documentation/devicetree/bindings/dma/fsl-edma.txt
index e77b08ebcd06..ee1754739b4b 100644
--- a/Documentation/devicetree/bindings/dma/fsl-edma.txt
+++ b/Documentation/devicetree/bindings/dma/fsl-edma.txt
@@ -10,7 +10,8 @@ Required properties:
- compatible :
- "fsl,vf610-edma" for eDMA used similar to that on Vybrid vf610 SoC
- "fsl,imx7ulp-edma" for eDMA2 used similar to that on i.mx7ulp
- - "fsl,fsl,ls1028a-edma" for eDMA used similar to that on Vybrid vf610 SoC
+ - "fsl,ls1028a-edma" followed by "fsl,vf610-edma" for eDMA used on the
+ LS1028A SoC.
- reg : Specifies base physical address(s) and size of the eDMA registers.
The 1st region is eDMA control register's address and size.
The 2nd and the 3rd regions are programmable channel multiplexing
diff --git a/Documentation/devicetree/bindings/net/dsa/b53.txt b/Documentation/devicetree/bindings/net/dsa/b53.txt
index 5201bc15fdd6..cfd1afdc6e94 100644
--- a/Documentation/devicetree/bindings/net/dsa/b53.txt
+++ b/Documentation/devicetree/bindings/net/dsa/b53.txt
@@ -110,6 +110,9 @@ Ethernet switch connected via MDIO to the host, CPU port wired to eth0:
#size-cells = <0>;
ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
port0@0 {
reg = <0>;
label = "lan1";
diff --git a/Documentation/usb/raw-gadget.rst b/Documentation/usb/raw-gadget.rst
index 9e78cb858f86..68d879a8009e 100644
--- a/Documentation/usb/raw-gadget.rst
+++ b/Documentation/usb/raw-gadget.rst
@@ -27,9 +27,8 @@ differences are:
3. Raw Gadget provides a way to select a UDC device/driver to bind to,
while GadgetFS currently binds to the first available UDC.
-4. Raw Gadget uses predictable endpoint names (handles) across different
- UDCs (as long as UDCs have enough endpoints of each required transfer
- type).
+4. Raw Gadget explicitly exposes information about endpoints addresses and
+ capabilities allowing a user to write UDC-agnostic gadgets.
5. Raw Gadget has ioctl-based interface instead of a filesystem-based one.
@@ -50,12 +49,36 @@ The typical usage of Raw Gadget looks like:
Raw Gadget and react to those depending on what kind of USB device
needs to be emulated.
+Note, that some UDC drivers have fixed addresses assigned to endpoints, and
+therefore arbitrary endpoint addresses can't be used in the descriptors.
+Nevertheles, Raw Gadget provides a UDC-agnostic way to write USB gadgets.
+the USB_RAW_IOCTL_EPS_INFO ioctl can be used to find out information about
+endpoints that the UDC driver has. Based on that information, the user must
+chose UDC endpoints that will be used for the gadget being emulated, and
+properly assign addresses in endpoint descriptors.
+You can find usage examples (along with a test suite) here:
+Internal details
+Currently every endpoint read/write ioctl submits a USB request and waits until
+its completion. This is the desired mode for coverage-guided fuzzing (as we'd
+like all USB request processing happen during the lifetime of a syscall),
+and must be kept in the implementation. (This might be slow for real world
+applications, thus the O_NONBLOCK improvement suggestion below.)
Potential future improvements
-- Implement ioctl's for setting/clearing halt status on endpoints.
-- Reporting more events (suspend, resume, etc.) through
+- Report more events (suspend, resume, etc.) through USB_RAW_IOCTL_EVENT_FETCH.
- Support O_NONBLOCK I/O.
+- Support USB 3 features (accept SS endpoint companion descriptor when
+ enabling endpoints; allow providing stream_id for bulk transfers).
+- Support ISO transfer features (expose frame_number for completed requests).