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2020-02-21bootconfig: Add append value operator supportMasami Hiramatsu
Add append value operator "+=" support to bootconfig syntax. With this operator, user can add new value to the key as an entry of array instead of overwriting. For example, foo = bar ... foo += baz Then the key "foo" has "bar" and "baz" values as an array. Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-21bootconfig: Prohibit re-defining value on same keyMasami Hiramatsu
Currently, bootconfig adds a new value on the existing key to the tail of an array. But this looks a bit confusing because an admin can easily rewrite the original value in the same config file. This rejects the following value re-definition. key = value1 ... key = value2 You should rewrite value1 to value2 in this case. Link: http://lkml.kernel.org/r/158227282199.12842.10110929876059658601.stgit@devnote2 Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [ Fixed spelling of arraies to arrays ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-20bootconfig: Reject subkey and value on same parent keyMasami Hiramatsu
Reject if a value node is mixed with subkey node on same parent key node. A value node can not co-exist with subkey node under some key node, e.g. key = value key.subkey = another-value This is not be allowed because bootconfig API is not designed to handle such case. Link: http://lkml.kernel.org/r/158220115232.26565.7792340045009731803.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-20bootconfig: Add bootconfig magic word for indicating bootconfig explicitlyMasami Hiramatsu
Add bootconfig magic word to the end of bootconfig on initrd image for indicating explicitly the bootconfig is there. Also tools/bootconfig treats wrong size or wrong checksum or parse error as an error, because if there is a bootconfig magic word, there must be a bootconfig. The bootconfig magic word is "#BOOTCONFIG\n", 12 bytes word. Thus the block image of the initrd file with bootconfig is as follows. [Initrd][bootconfig][size][csum][#BOOTCONFIG\n] Link: http://lkml.kernel.org/r/158220112263.26565.3944814205960612841.stgit@devnote2 Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05bootconfig: Only load bootconfig if "bootconfig" is on the kernel cmdlineSteven Rostedt (VMware)
As the bootconfig is appended to the initrd it is not as easy to modify as the kernel command line. If there's some issue with the kernel, and the developer wants to boot a pristine kernel, it should not be needed to modify the initrd to remove the bootconfig for a single boot. As bootconfig is silently added (if the admin does not know where to look they may not know it's being loaded). It should be explicitly added to the kernel cmdline. The loading of the bootconfig is only done if "bootconfig" is on the kernel command line. This will let admins know that the kernel command line is extended. Note, after adding printk()s for when the size is too great or the checksum is wrong, exposed that the current method always looked for the boot config, and if this size and checksum matched, it would parse it (as if either is wrong a printk has been added to show this). It's better to only check this if the boot config is asked to be looked for. Link: https://lore.kernel.org/r/CAHk-=wjfjO+h6bQzrTf=YCZA53Y3EDyAs3Z4gEsT7icA3u_Psw@mail.gmail.com Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-21Documentation: bootconfig: Fix typos in bootconfig documentationMasami Hiramatsu
Fix typos in bootconfig.rst according to Randy's suggestions. Link: http://lkml.kernel.org/r/157949059219.25888.16939971423610233631.stgit@devnote2 Suggested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13Documentation: tracing: Add boot-time tracing documentMasami Hiramatsu
Add a documentation about boot-time tracing options in boot config. Link: http://lkml.kernel.org/r/157867246028.17873.8047384554383977870.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13Documentation: bootconfig: Add a doc for extended boot configMasami Hiramatsu
Add a documentation for extended boot config under admin-guide, since it is including the syntax of boot config. Link: http://lkml.kernel.org/r/157867230658.17873.9309879174829924324.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>