diff options
author | Stephen Rothwell <sfr@canb.auug.org.au> | 2010-08-05 11:14:16 +1000 |
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committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2010-08-05 11:14:16 +1000 |
commit | 523f43a795e77e62267886d3a812f24f1f94678e (patch) | |
tree | 05905bd4babb7f1aa392fe949d014bbbda5fd432 /Documentation | |
parent | 21b7b807b3bf9c26aa9dfb1387b01bb2c67eb743 (diff) | |
parent | 4630da333a416c71313ea084b3f5ea29fa27d3a6 (diff) |
Merge remote branch 'kbuild/for-next'
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/coccinelle.txt | 258 | ||||
-rw-r--r-- | Documentation/kbuild/kbuild.txt | 26 | ||||
-rw-r--r-- | Documentation/kbuild/kconfig.txt | 2 | ||||
-rw-r--r-- | Documentation/kbuild/makefiles.txt | 27 |
4 files changed, 305 insertions, 8 deletions
diff --git a/Documentation/coccinelle.txt b/Documentation/coccinelle.txt new file mode 100644 index 000000000000..cd2b02837066 --- /dev/null +++ b/Documentation/coccinelle.txt @@ -0,0 +1,258 @@ +Copyright 2010 Nicolas Palix <npalix@diku.dk> +Copyright 2010 Julia Lawall <julia@diku.dk> +Copyright 2010 Gilles Muller <Gilles.Muller@lip6.fr> + + + Getting Coccinelle +~~~~~~~~~~~~~~~~~~~~ + +The semantic patches included in the kernel use the 'virtual rule' +feature which was introduced in Coccinelle version 0.1.11. + +Coccinelle (>=0.2.0) is available through the package manager +of many distributions, e.g. : + + - Debian (>=squeeze) + - Fedora (>=13) + - Ubuntu (>=10.04 Lucid Lynx) + - OpenSUSE + - Arch Linux + - NetBSD + - FreeBSD + + +You can get the latest version released from the Coccinelle homepage at +http://coccinelle.lip6.fr/ + +Once you have it, run the following command: + + ./configure + make + +as a regular user, and install it with + + sudo make install + + + Using Coccinelle on the Linux kernel +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +A Coccinelle-specific target is defined in the top level +Makefile. This target is named 'coccicheck' and calls the 'coccicheck' +front-end in the 'scripts' directory. + +Four modes are defined: report, patch, context, and org. The mode to +use is specified by setting the MODE variable with 'MODE=<mode>'. + +'report' generates a list in the following format: + file:line:column-column: message + +'patch' proposes a fix, when possible. + +'context' highlights lines of interest and their context in a +diff-like style.Lines of interest are indicated with '-'. + +'org' generates a report in the Org mode format of Emacs. + +Note that not all semantic patches implement all modes. + +To make a report for every semantic patch, run the following command: + + make coccicheck MODE=report + +NB: The 'report' mode is the default one. + +To produce patches, run: + + make coccicheck MODE=patch + + +The coccicheck target applies every semantic patch available in the +subdirectories of 'scripts/coccinelle' to the entire Linux kernel. + +For each semantic patch, a changelog message is proposed. It gives a +description of the problem being checked by the semantic patch, and +includes a reference to Coccinelle. + +As any static code analyzer, Coccinelle produces false +positives. Thus, reports must be carefully checked, and patches +reviewed. + + + Using Coccinelle with a single semantic patch +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The optional make variable COCCI can be used to check a single +semantic patch. In that case, the variable must be initialized with +the name of the semantic patch to apply. + +For instance: + + make coccicheck COCCI=<my_SP.cocci> MODE=patch +or + make coccicheck COCCI=<my_SP.cocci> MODE=report + + + Proposing new semantic patches +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +New semantic patches can be proposed and submitted by kernel +developers. For sake of clarity, they should be organized in the +subdirectories of 'scripts/coccinelle/'. + + + Detailed description of the 'report' mode +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +'report' generates a list in the following format: + file:line:column-column: message + +Example: + +Running + + make coccicheck MODE=report COCCI=scripts/coccinelle/err_cast.cocci + +will execute the following part of the SmPL script. + +<smpl> +@r depends on !context && !patch && (org || report)@ +expression x; +position p; +@@ + + ERR_PTR@p(PTR_ERR(x)) + +@script:python depends on report@ +p << r.p; +x << r.x; +@@ + +msg="ERR_CAST can be used with %s" % (x) +coccilib.report.print_report(p[0], msg) +</smpl> + +This SmPL excerpt generates entries on the standard output, as +illustrated below: + +/home/user/linux/crypto/ctr.c:188:9-16: ERR_CAST can be used with alg +/home/user/linux/crypto/authenc.c:619:9-16: ERR_CAST can be used with auth +/home/user/linux/crypto/xts.c:227:9-16: ERR_CAST can be used with alg + + + Detailed description of the 'patch' mode +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +When the 'patch' mode is available, it proposes a fix for each problem +identified. + +Example: + +Running + make coccicheck MODE=patch COCCI=scripts/coccinelle/err_cast.cocci + +will execute the following part of the SmPL script. + +<smpl> +@ depends on !context && patch && !org && !report @ +expression x; +@@ + +- ERR_PTR(PTR_ERR(x)) ++ ERR_CAST(x) +</smpl> + +This SmPL excerpt generates patch hunks on the standard output, as +illustrated below: + +diff -u -p a/crypto/ctr.c b/crypto/ctr.c +--- a/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200 ++++ b/crypto/ctr.c 2010-06-03 23:44:49.000000000 +0200 +@@ -185,7 +185,7 @@ static struct crypto_instance *crypto_ct + alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER, + CRYPTO_ALG_TYPE_MASK); + if (IS_ERR(alg)) +- return ERR_PTR(PTR_ERR(alg)); ++ return ERR_CAST(alg); + + /* Block size must be >= 4 bytes. */ + err = -EINVAL; + + Detailed description of the 'context' mode +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +'context' highlights lines of interest and their context +in a diff-like style. + +NOTE: The diff-like output generated is NOT an applicable patch. The + intent of the 'context' mode is to highlight the important lines + (annotated with minus, '-') and gives some surrounding context + lines around. This output can be used with the diff mode of + Emacs to review the code. + +Example: + +Running + make coccicheck MODE=context COCCI=scripts/coccinelle/err_cast.cocci + +will execute the following part of the SmPL script. + +<smpl> +@ depends on context && !patch && !org && !report@ +expression x; +@@ + +* ERR_PTR(PTR_ERR(x)) +</smpl> + +This SmPL excerpt generates diff hunks on the standard output, as +illustrated below: + +diff -u -p /home/user/linux/crypto/ctr.c /tmp/nothing +--- /home/user/linux/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200 ++++ /tmp/nothing +@@ -185,7 +185,6 @@ static struct crypto_instance *crypto_ct + alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER, + CRYPTO_ALG_TYPE_MASK); + if (IS_ERR(alg)) +- return ERR_PTR(PTR_ERR(alg)); + + /* Block size must be >= 4 bytes. */ + err = -EINVAL; + + Detailed description of the 'org' mode +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +'org' generates a report in the Org mode format of Emacs. + +Example: + +Running + make coccicheck MODE=org COCCI=scripts/coccinelle/err_cast.cocci + +will execute the following part of the SmPL script. + +<smpl> +@r depends on !context && !patch && (org || report)@ +expression x; +position p; +@@ + + ERR_PTR@p(PTR_ERR(x)) + +@script:python depends on org@ +p << r.p; +x << r.x; +@@ + +msg="ERR_CAST can be used with %s" % (x) +msg_safe=msg.replace("[","@(").replace("]",")") +coccilib.org.print_todo(p[0], msg_safe) +</smpl> + +This SmPL excerpt generates Org entries on the standard output, as +illustrated below: + +* TODO [[view:/home/user/linux/crypto/ctr.c::face=ovl-face1::linb=188::colb=9::cole=16][ERR_CAST can be used with alg]] +* TODO [[view:/home/user/linux/crypto/authenc.c::face=ovl-face1::linb=619::colb=9::cole=16][ERR_CAST can be used with auth]] +* TODO [[view:/home/user/linux/crypto/xts.c::face=ovl-face1::linb=227::colb=9::cole=16][ERR_CAST can be used with alg]] diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index 0d8addbb0fae..1e5165aa9e4e 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -22,11 +22,33 @@ building C files and assembler files. KAFLAGS -------------------------------------------------- -Additional options to the assembler. +Additional options to the assembler (for built-in and modules). + +AFLAGS_MODULE +-------------------------------------------------- +Addtional module specific options to use for $(AS). + +AFLAGS_KERNEL +-------------------------------------------------- +Addtional options for $(AS) when used for assembler +code for code that is compiled as built-in. KCFLAGS -------------------------------------------------- -Additional options to the C compiler. +Additional options to the C compiler (for built-in and modules). + +CFLAGS_KERNEL +-------------------------------------------------- +Addtional options for $(CC) when used to compile +code that is compiled as built-in. + +CFLAGS_MODULE +-------------------------------------------------- +Addtional module specific options to use for $(CC). + +LDFLAGS_MODULE +-------------------------------------------------- +Additional options used for $(LD) when linking modules. KBUILD_VERBOSE -------------------------------------------------- diff --git a/Documentation/kbuild/kconfig.txt b/Documentation/kbuild/kconfig.txt index b2cb16ebcb16..cca46b1a0f6c 100644 --- a/Documentation/kbuild/kconfig.txt +++ b/Documentation/kbuild/kconfig.txt @@ -65,7 +65,7 @@ also use the environment variable KCONFIG_ALLCONFIG as a flag or a filename that contains config symbols that the user requires to be set to a specific value. If KCONFIG_ALLCONFIG is used without a filename, "make *config" checks for a file named -"all{yes/mod/no/random}.config" (corresponding to the *config command +"all{yes/mod/no/def/random}.config" (corresponding to the *config command that was used) for symbol values that are to be forced. If this file is not found, it checks for a file named "all.config" to contain forced values. diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 8abd041b605d..c375313cb128 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -921,16 +921,33 @@ When kbuild executes, the following steps are followed (roughly): The first example utilises the trick that a config option expands to 'y' when selected. - CFLAGS_KERNEL $(CC) options specific for built-in + KBUILD_AFLAGS_KERNEL $(AS) options specific for built-in - $(CFLAGS_KERNEL) contains extra C compiler flags used to compile + $(KBUILD_AFLAGS_KERNEL) contains extra C compiler flags used to compile resident kernel code. - CFLAGS_MODULE $(CC) options specific for modules + KBUILD_AFLAGS_MODULE Options for $(AS) when building modules - $(CFLAGS_MODULE) contains extra C compiler flags used to compile code - for loadable kernel modules. + $(KBUILD_AFLAGS_MODULE) is used to add arch specific options that + are used for $(AS). + From commandline AFLAGS_MODULE shall be used (see kbuild.txt). + KBUILD_CFLAGS_KERNEL $(CC) options specific for built-in + + $(KBUILD_CFLAGS_KERNEL) contains extra C compiler flags used to compile + resident kernel code. + + KBUILD_CFLAGS_MODULE Options for $(CC) when building modules + + $(KBUILD_CFLAGS_MODULE) is used to add arch specific options that + are used for $(CC). + From commandline CFLAGS_MODULE shall be used (see kbuild.txt). + + KBUILD_LDFLAGS_MODULE Options for $(LD) when linking modules + + $(KBUILD_LDFLAGS_MODULE) is used to add arch specific options + used when linking modules. This is often a linker script. + From commandline LDFLAGS_MODULE shall be used (see kbuild.txt). --- 6.2 Add prerequisites to archprepare: |