[PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Horst Schirmeier]

Hello,

the kbuild-dont-put-temp-files-in-the-source-tree.patch (-mm patches) is
implemented faultily and fails in its intention to put temporary files
in $TMPDIR (or /tmp by default).

This is the code as it results from the patch:

ASTMP = $(shell mktemp ${TMPDIR:-/tmp}/asXXXXXX)
as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o $ASTMP ; \
 		   then echo "$(2)"; else echo "$(3)"; fi; \
	           rm -f $ASTMP)

1) $ needs to be escaped in the shell function call, otherwise make
   tries to substitute with a (in this case not existing) make variable
   with this name.

2) Makefile variable names need to be put in parentheses; $ASTMP is
   being interpreted as $(A)STMP, resulting in as-instr writing to a file
   named after whatever is in $(A), followed by "STMP".

3) ld-option also writes to a temporary file and needs the same
   treatment.

Please consider using the corrected patch below instead. Alternatively,
we could also simply use -o /dev/null, as we are not interested in the
output anyways. Daniel Drake already suggested this in a LKML post
(message-id 452F9602.1050906@gentoo.org).

It would also be nice if this would make it into the mainline kernel
before 2.6.19 gets released; this would help avoiding the sandbox
violation problems on Gentoo Linux [1] [2].

Kind regards,
 Horst Schirmeier

[1] http://bugs.gentoo.org/show_bug.cgi?id=149307
[2] LKML Message-ID: <451ABE0E.2030904@web.de>

---
http://bugzilla.kernel.org/show_bug.cgi?id=7261 berates us for putting a
temporary file into the kernel source tree.  Use mktemp instead.

Cc: Andi Kleen <ak@suse.de>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: jpdenheijer@gmail.com,
Signed-off-by: Horst Schirmeier <horst@schirmeier.com>
---

 Kbuild.include |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

--- linux-mm/scripts/Kbuild.include.orig	2006-10-29 00:39:35.000000000 +0200
+++ linux-mm/scripts/Kbuild.include	2006-10-29 00:41:43.000000000 +0200
@@ -66,9 +66,10 @@ as-option = $(shell if $(CC) $(CFLAGS) $
 # as-instr
 # Usage: cflags-y += $(call as-instr, instr, option1, option2)
 
-as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o astest$$$$.out ; \
+ASTMP = $(shell mktemp $${TMPDIR:-/tmp}/asXXXXXX)
+as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o $(ASTMP) ; \
 		   then echo "$(2)"; else echo "$(3)"; fi; \
-	           rm -f astest$$$$.out)
+	           rm -f $(ASTMP))
 
 # cc-option
 # Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
@@ -97,10 +98,11 @@ cc-ifversion = $(shell if [ $(call cc-ve
 
 # ld-option
 # Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
+LDTMP = $(shell mktemp $${TMPDIR:-/tmp}/ldXXXXXX)
 ld-option = $(shell if $(CC) $(1) \
-			     -nostdlib -o ldtest$$$$.out -xc /dev/null \
+			     -nostdlib -o $(LDTMP) -xc /dev/null \
              > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi; \
-	     rm -f ldtest$$$$.out)
+	     rm -f $(LDTMP))
 
 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Andi Kleen]

On Saturday 28 October 2006 16:07, Horst Schirmeier wrote:
> Hello,
>
> the kbuild-dont-put-temp-files-in-the-source-tree.patch (-mm patches) is
> implemented faultily and fails in its intention to put temporary files
> in $TMPDIR (or /tmp by default).
>
> This is the code as it results from the patch:
>
> ASTMP = $(shell mktemp ${TMPDIR:-/tmp}/asXXXXXX)

I'm still against mktemp. It eats random entropy and
temporary files should be in the objdir, not in /tmp

-Andi

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Horst Schirmeier]

On Sat, 28 Oct 2006, Andi Kleen wrote:
> On Saturday 28 October 2006 16:07, Horst Schirmeier wrote:
> > Hello,
> >
> > the kbuild-dont-put-temp-files-in-the-source-tree.patch (-mm patches) is
> > implemented faultily and fails in its intention to put temporary files
> > in $TMPDIR (or /tmp by default).
> >
> > This is the code as it results from the patch:
> >
> > ASTMP = $(shell mktemp ${TMPDIR:-/tmp}/asXXXXXX)
> 
> I'm still against mktemp. It eats random entropy and
> temporary files should be in the objdir, not in /tmp

TBH, I don't see the necessity of temporary files at all in this case,
but I assumed there must be a reason for them as the change already made
it into the -mm tree.

Why not use -o /dev/null, as Daniel Drake already suggested in [1]? In
both as-instr and ld-option, the tmp file is being deleted
unconditionally right after its creation anyways.

The attached patch is adapted from the patches proposed in [2], redone
as a replacement for
kbuild-dont-put-temp-files-in-the-source-tree.patch. Comments?

Kind regards,
 Horst

[1] LKML Message-ID: <452F9602.1050906@gentoo.org>
[2] http://bugs.gentoo.org/show_bug.cgi?id=149307

---
Do not write temporary files in as-instr and ld-option but write to
/dev/null, as the output is not being used anyways.

Cc: Andi Kleen <ak@suse.de>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: jpdenheijer@gmail.com
Signed-off-by: Horst Schirmeier <horst@schirmeier.com>
---

 Kbuild.include |   10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

--- linux-mm/scripts/Kbuild.include.orig	2006-10-29 00:39:35.000000000 +0200
+++ linux-mm/scripts/Kbuild.include	2006-10-29 12:56:39.000000000 +0100
@@ -66,9 +66,8 @@ as-option = $(shell if $(CC) $(CFLAGS) $
 # as-instr
 # Usage: cflags-y += $(call as-instr, instr, option1, option2)
 
-as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o astest$$$$.out ; \
-		   then echo "$(2)"; else echo "$(3)"; fi; \
-	           rm -f astest$$$$.out)
+as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o /dev/null ; \
+		   then echo "$(2)"; else echo "$(3)"; fi)
 
 # cc-option
 # Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
@@ -98,9 +97,8 @@ cc-ifversion = $(shell if [ $(call cc-ve
 # ld-option
 # Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
 ld-option = $(shell if $(CC) $(1) \
-			     -nostdlib -o ldtest$$$$.out -xc /dev/null \
-             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi; \
-	     rm -f ldtest$$$$.out)
+			     -nostdlib -o /dev/null -xc /dev/null \
+             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi)
 
 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Andi Kleen]

> Why not use -o /dev/null, as Daniel Drake already suggested in [1]? In
> both as-instr and ld-option, the tmp file is being deleted
> unconditionally right after its creation anyways.

Because then when the compilation runs as root some as versions
will delete /dev/null on a error. This has happened in the past.

-Andi

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Oleg Verych]

On 2006-10-29, Andi Kleen wrote:
>> Why not use -o /dev/null, as Daniel Drake already suggested in [1]? In
>> both as-instr and ld-option, the tmp file is being deleted
>> unconditionally right after its creation anyways.
>
> Because then when the compilation runs as root some as versions
> will delete /dev/null on a error. This has happened in the past.

OK, but let users, who still build kernels as root, alone.

In `19-rc3/include/Kbuild.include', just below `as-instr' i see:
,--
|cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
|             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
|
|# cc-option-yn
|# Usage: flag := $(call cc-option-yn, -march=winchip-c6)
|cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
|                 > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
`--
so, change to `-o /dev/null' in `as-instr' will just follow this.
____

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Sam Ravnborg]

On Sun, Oct 29, 2006 at 05:58:56PM +0000, Oleg Verych wrote:
> 
> On 2006-10-29, Andi Kleen wrote:
> >> Why not use -o /dev/null, as Daniel Drake already suggested in [1]? In
> >> both as-instr and ld-option, the tmp file is being deleted
> >> unconditionally right after its creation anyways.
> >
> > Because then when the compilation runs as root some as versions
> > will delete /dev/null on a error. This has happened in the past.
> 
> OK, but let users, who still build kernels as root, alone.
This needs to work - there are too much people that continue to do so.
And gentoo books recommended this last time I looked.

> 
> In `19-rc3/include/Kbuild.include', just below `as-instr' i see:
> ,--
> |cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
> |             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
> |
> |# cc-option-yn
> |# Usage: flag := $(call cc-option-yn, -march=winchip-c6)
> |cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
> |                 > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
> `--
> so, change to `-o /dev/null' in `as-instr' will just follow this.

gcc does not delete files specified with -o - but binutils does.
So using /dev/null in this case is not an option.

	Sam

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Jan Beulich]

>> In `19-rc3/include/Kbuild.include', just below `as-instr' i see:
>> ,--
>> |cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
>> |             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
>> |
>> |# cc-option-yn
>> |# Usage: flag := $(call cc-option-yn, -march=winchip-c6)
>> |cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
>> |                 > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
>> `--
>> so, change to `-o /dev/null' in `as-instr' will just follow this.
>
>gcc does not delete files specified with -o - but binutils does.
>So using /dev/null in this case is not an option.

While I fixed this quite some time ago (after running into it myself), it
obviously still is a problem with older versions. However, using as' -Z
option seems to help here.
On the other hand, I long wanted to compose a patch to do away
with all the .tmp_* things at the build root, and move them into a
single .tmp/ directory - this would also seem to make a nice place to
put all sort of other temporary files in... I just never found the time
to actually do that, sorry.

Jan

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Oleg Verych]

On 2006-10-30, Jan Beulich wrote:
>
>>> In `19-rc3/include/Kbuild.include', just below `as-instr' i see:
>>> ,--
>>> |cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
>>> |             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
>>> |
>>> |# cc-option-yn
>>> |# Usage: flag := $(call cc-option-yn, -march=winchip-c6)
>>> |cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
>>> |                 > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
>>> `--
>>> so, change to `-o /dev/null' in `as-instr' will just follow this.
>>
>>gcc does not delete files specified with -o - but binutils does.
>>So using /dev/null in this case is not an option.

Hmm. What's the preblem to invoke `as' via the GNU C compiler, then?

> While I fixed this quite some time ago (after running into it myself), it
> obviously still is a problem with older versions. However, using as' -Z
> option seems to help here.
> On the other hand, I long wanted to compose a patch to do away
> with all the .tmp_* things at the build root, and move them into a
> single .tmp/ directory - this would also seem to make a nice place to
> put all sort of other temporary files in... I just never found the time
> to actually do that, sorry.

Maybe it's good idea, let me try, as i already bound to kbuild fixes.

But now, i'm just using KBUILD_OUTPUT=/tmp/, and /tmp/ is /dev/shm/.
It speeds up things on testing and small amounts of stuff to build.
Source tree is for patching only.
____

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Oleg Verych]

On 2006-10-30, Jan Beulich wrote:
>
>>>gcc does not delete files specified with -o - but binutils does.
>>>So using /dev/null in this case is not an option.
>>
>>Hmm. What's the preblem to invoke `as' via the GNU C compiler, then?
>
>Older gas, whether invoked from gcc or the command line or elsewhere,
>deletes its output on error, regardless of whether this is a special file
>(device). gcc can't make gas not do so.

So, how about (using your btmp directory) create symlink to /dev/null in
the (dev) sub-directory and then set no write permission? No tmp,
things are local to build output, old gas's happy:
,__
|olecom@flower:/tmp/_build_2.6.19-rc3/btmp
!__$ mkdir dev
,__
|olecom@flower:/tmp/_build_2.6.19-rc3/btmp
!__$ cd dev ; ln -s /dev/null null ; chmod u-w . ; ls -la
total 0
dr-xr-x--- 2 olecom root 60 2006-10-30 15:34 .
drwxr-x--- 3 olecom root 80 2006-10-30 15:34 ..
lrwxrwxrwx 1 olecom root  9 2006-10-30 15:34 null -> /dev/null
,__
|olecom@flower:/tmp/_build_2.6.19-rc3/btmp/dev
!__$ cd .. ; rm dev/null
rm: cannot remove dev/null': Permission denied
,__
|olecom@flower:/tmp/_build_2.6.19-rc3/btmp
!__$ echo ok > dev/null
,__
|olecom@flower:/tmp/_build_2.6.19-rc3/btmp
!__$

New featured dev/null may be set in some kind of make variable, say
$(null) in scripts/Kbuild.include.
____

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Valdis.Kletnieks]

[-- Attachment #1: Type: text/plain, Size: 1284 bytes --]

On Mon, 30 Oct 2006 14:42:16 GMT, Oleg Verych said:

> So, how about (using your btmp directory) create symlink to /dev/null in
> the (dev) sub-directory and then set no write permission? No tmp,
> things are local to build output, old gas's happy:
> ,__
> |olecom@flower:/tmp/_build_2.6.19-rc3/btmp
> !__$ mkdir dev
> ,__
> |olecom@flower:/tmp/_build_2.6.19-rc3/btmp
> !__$ cd dev ; ln -s /dev/null null ; chmod u-w . ; ls -la
> total 0
> dr-xr-x--- 2 olecom root 60 2006-10-30 15:34 .
> drwxr-x--- 3 olecom root 80 2006-10-30 15:34 ..
> lrwxrwxrwx 1 olecom root  9 2006-10-30 15:34 null -> /dev/null
> ,__
> |olecom@flower:/tmp/_build_2.6.19-rc3/btmp/dev
> !__$ cd .. ; rm dev/null
> rm: cannot remove dev/null': Permission denied

Did you try this as root, which is where the original "/dev/null dissapears"
problem shows up?

[/tmp]3 id
uid=0(root) gid=0(root) groups=0(root),1(bin),2(daemon),3(sys),4(adm),6(disk),10(wheel) context=valdis:staff_r:staff_t
[/tmp]3 mkdir z9
[/tmp]3 touch z9/foo
[/tmp]3 chmod 0 z9
[/tmp]3 rm z9/foo
[/tmp]3 ln -s /dev/null z9
[/tmp]3 ls -l z9
total 0
lrwxrwxrwx 1 root root 9 Oct 30 10:20 null -> /dev/null
[/tmp]3 rm z9/null
[/tmp]3 ls -ld z9
d--------- 2 root root 40 Oct 30 10:21 z9

Hmm.. and even the 'ln' worked even when z9 was chmod 0. ;)


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Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Oleg Verych]

On 2006-10-30, Valdis.Kletnieks wrote:
>
> Hmm.. and even the 'ln' worked even when z9 was chmod 0. ;)
(WTF! I'm no wonder any more, why all that selinux was brought ;)

Well, i've said already about roots in post above.
This fix is for needless mktemp and old binutils.

Fix for roots:
,--
|if [ `id -u` == "0" ]; then echo "Root landed !!!"; ! true; fi
`--
More polite fools-protection, with guaranteed permission from the user:
,--
|if [ `id -u` == "0" ]; then useradd bkernel && su bkernel fi;
`--
____

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Oleg Verych]

On 2006-10-30, <olecom@flower> wrote:
> Fix for roots:
> ,--
>|if [ `id -u` == "0" ]; then echo "Root landed !!!"; ! true; fi
> `--
> More polite fools-protection, with guaranteed permission from the user:
> ,--
>|if [ `id -u` == "0" ]; then useradd bkernel && su bkernel fi;
> `--
> ____

For current state of things, i wish to propose

kbuild-mm-more-option-check-fixes.pre-patch:

Request For Testing.

Interested parties may test this one.
$(ret) is used for debug. In final version it may be removed,
$(objtree)/null must be known for clean targets.

I've replaced one `echo -e' with `printf', because, for example, my shell is
not bash, and built-in `echo' have not `-e' option, `printf' works everywhere.
[trailing spaces killed: +1]

Any comments are appreciated.
____

--- linux-2.6.19-rc3-mm1/scripts/Kbuild.include	2006-10-28 01:26:25.000000000 +0000
+++ linux-2.6.19-rc3-mm1/scripts/Kbuild.include~more-option-check-fixes	2006-10-30 20:39:03.641018805 +0000
@@ -7,6 +7,15 @@ squote  := '
 empty   :=
 space   := $(empty) $(empty)
 
+# Immortal null for mortals and roots
+define null
+  $(shell \
+    if test -L null; \
+      then echo null; \
+      else rm -f null; ln -s /dev/null null; \
+    fi)
+endef
+
 ###
 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
 dot-target = $(dir $@).$(notdir $@)
@@ -56,30 +65,46 @@ endef
 # gcc support functions
 # See documentation in Documentation/kbuild/makefiles.txt
 
+ret = echo "$(1)" ; echo "$(1)" >> results.txt
 # as-option
 # Usage: cflags-y += $(call as-option, -Wa$(comma)-isa=foo,)
-
-as-option = $(shell if $(CC) $(CFLAGS) $(1) -Wa,-Z -c -o /dev/null \
-	     -xassembler /dev/null > /dev/null 2>&1; then echo "$(1)"; \
-	     else echo "$(2)"; fi ;)
+define as-option
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -c -o $(null) -xassembler null >null 2>&1; \
+      then $(call ret,"$(1)"); \
+      else $(call ret,"$(2)"); \
+    fi)
+endef
 
 # as-instr
 # Usage: cflags-y += $(call as-instr, instr, option1, option2)
-
-as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o astest$$$$.out ; \
-		   then echo "$(2)"; else echo "$(3)"; fi; \
-	           rm -f astest$$$$.out)
+define as-instr
+  $(shell \
+    if printf "$(1)" | $(AS) >null 2>&1 -W -o $(null); \
+      then $(call ret,"$(2)"); \
+      else $(call ret,"$(3)"); \
+    fi)
+endef
 
 # cc-option
 # Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
-
-cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
-             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
+define cc-option
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -S -o $(null) -xc null >null 2>&1; \
+      then $(call ret,"$(1)"); \
+      else $(call ret,"$(2)"); \
+    fi)
+endef
 
 # cc-option-yn
 # Usage: flag := $(call cc-option-yn, -march=winchip-c6)
-cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
-                > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
+define cc-option-yn
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -S -o $(null) -xc null >null 2>&1; \
+      then $(call ret,"y"); \
+      else $(call ret,"n"); \
+    fi)
+endef
 
 # cc-option-align
 # Prefix align with either -falign or -malign
@@ -97,10 +122,13 @@ cc-ifversion = $(shell if [ $(call cc-ve
 
 # ld-option
 # Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
-ld-option = $(shell if $(CC) $(1) \
-			     -nostdlib -o ldtest$$$$.out -xc /dev/null \
-             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi; \
-	     rm -f ldtest$$$$.out)
+define ld-option
+  $(shell \
+    if $(CC) $(1) -nostdlib -o $(null) -xc null >null 2>&1; \
+      then $(call ret,"$(1)"); \
+      else $(call ret,"$(2)"); \
+    fi)
+endef
 
 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
@@ -120,7 +148,7 @@ cmd = @$(echo-cmd) $(cmd_$(1))
 objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
 
 ###
-# if_changed      - execute command if any prerequisite is newer than 
+# if_changed      - execute command if any prerequisite is newer than
 #                   target, or command line has changed
 # if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
 #                   including used config symbols

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Horst Schirmeier]

On Mon, 30 Oct 2006, Oleg Verych wrote:
> For current state of things, i wish to propose
> 
> kbuild-mm-more-option-check-fixes.pre-patch:
> 
> Request For Testing.
> 
> Interested parties may test this one.
> $(ret) is used for debug. In final version it may be removed,
> $(objtree)/null must be known for clean targets.
> 
> I've replaced one `echo -e' with `printf', because, for example, my shell is
> not bash, and built-in `echo' have not `-e' option, `printf' works everywhere.
> [trailing spaces killed: +1]
> 
> Any comments are appreciated.

The problem is, this brings us back to the problem where this whole
patch orgy began: Gentoo Portage sandbox violations when writing (the
null symlink) to the kernel tree when building external modules. What
about using $(M) as a base directory if it is defined?

--- linux-mm/scripts/Kbuild.include.orig	2006-10-31 01:06:13.000000000 +0100
+++ linux-mm/scripts/Kbuild.include	2006-10-31 01:07:01.000000000 +0100
@@ -7,6 +7,20 @@ squote  := '
 empty   :=
 space   := $(empty) $(empty)
 
+# Immortal null for mortals and roots
+ifdef M
+  null = $(M)/null
+else
+  null = null
+endif
+define createnull
+  $(shell \
+    if test -L $(null); \
+      then echo $(null); \
+      else rm -f $(null); ln -s /dev/null $(null); \
+    fi)
+endef
+
 ###
 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
 dot-target = $(dir $@).$(notdir $@)
@@ -56,30 +70,46 @@ endef
 # gcc support functions
 # See documentation in Documentation/kbuild/makefiles.txt
 
+ret = echo "$(1)" ; echo "$(1)" >> results.txt
 # as-option
 # Usage: cflags-y += $(call as-option, -Wa$(comma)-isa=foo,)
-
-as-option = $(shell if $(CC) $(CFLAGS) $(1) -Wa,-Z -c -o /dev/null \
-	     -xassembler /dev/null > /dev/null 2>&1; then echo "$(1)"; \
-	     else echo "$(2)"; fi ;)
+define as-option
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -c -o $(createnull) -xassembler $(null) >$(null) 2>&1; \
+      then $(call ret,"$(1)"); \
+      else $(call ret,"$(2)"); \
+    fi)
+endef
 
 # as-instr
 # Usage: cflags-y += $(call as-instr, instr, option1, option2)
-
-as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o astest$$$$.out ; \
-		   then echo "$(2)"; else echo "$(3)"; fi; \
-	           rm -f astest$$$$.out)
+define as-instr
+  $(shell \
+    if printf "$(1)" | $(AS) >$(createnull) 2>&1 -W -o $(null); \
+      then $(call ret,"$(2)"); \
+      else $(call ret,"$(3)"); \
+    fi)
+endef
 
 # cc-option
 # Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
-
-cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
-             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
+define cc-option
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -S -o $(createnull) -xc $(null) >$(null) 2>&1; \
+      then $(call ret,"$(1)"); \
+      else $(call ret,"$(2)"); \
+    fi)
+endef
 
 # cc-option-yn
 # Usage: flag := $(call cc-option-yn, -march=winchip-c6)
-cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
-                > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
+define cc-option-yn
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -S -o $(createnull) -xc $(null) >$(null) 2>&1; \
+      then $(call ret,"y"); \
+      else $(call ret,"n"); \
+    fi)
+endef
 
 # cc-option-align
 # Prefix align with either -falign or -malign
@@ -97,10 +127,13 @@ cc-ifversion = $(shell if [ $(call cc-ve
 
 # ld-option
 # Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
-ld-option = $(shell if $(CC) $(1) \
-			     -nostdlib -o ldtest$$$$.out -xc /dev/null \
-             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi; \
-	     rm -f ldtest$$$$.out)
+define ld-option
+  $(shell \
+    if $(CC) $(1) -nostdlib -o $(createnull) -xc $(null) >$(null) 2>&1; \
+      then $(call ret,"$(1)"); \
+      else $(call ret,"$(2)"); \
+    fi)
+endef
 
 ###
 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
@@ -120,7 +153,7 @@ cmd = @$(echo-cmd) $(cmd_$(1))
 objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
 
 ###
-# if_changed      - execute command if any prerequisite is newer than 
+# if_changed      - execute command if any prerequisite is newer than
 #                   target, or command line has changed
 # if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies
 #                   including used config symbols

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Andi Kleen]

> The problem is, this brings us back to the problem where this whole
> patch orgy began: Gentoo Portage sandbox violations when writing (the
> null symlink) to the kernel tree when building external modules. What
> about using $(M) as a base directory if it is defined?

I think Jan's $(objdir)/.tmp proposal would be cleanest. Just someone
has to implement it :)

-Andi

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Horst Schirmeier]

On Mon, 30 Oct 2006, Oleg Verych wrote:
> +# Immortal null for mortals and roots
> +define null
> +  $(shell \
> +    if test -L null; \
> +      then echo null; \
> +      else rm -f null; ln -s /dev/null null; \
> +    fi)
> +endef

Another remark: the 'else' branch should echo null, too.

# Immortal null for mortals and roots
define null
  $(shell \
    if test ! -L null; \
      then rm -f null; ln -s /dev/null null; \
    fi; \
    echo null)
endef

My patch proposal (the $(M) one) has the same bug.

Kind regards,
 Horst

-- 
PGP-Key 0xD40E0E7A

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Horst Schirmeier]

On Tue, 31 Oct 2006, Andi Kleen wrote:
> 
> > The problem is, this brings us back to the problem where this whole
> > patch orgy began: Gentoo Portage sandbox violations when writing (the
> > null symlink) to the kernel tree when building external modules. What
> > about using $(M) as a base directory if it is defined?
> 
> I think Jan's $(objdir)/.tmp proposal would be cleanest. Just someone
> has to implement it :)
> 
> -Andi

I'm not sure what you mean by $(objdir); I just got something to work
which creates the /dev/null symlink in a (newly created if necessary)
directory named

$(firstword $(obj-dirs) $(M))/.tmp

which seems to be a good place for both normal kernel builds and
external modules. External module builds seem not to set $(obj-dirs)...
Objections?

Kind regards,
 Horst

-- 
PGP-Key 0xD40E0E7A

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Oleg Verych]

On Tue, Oct 31, 2006 at 01:27:57AM +0100, Horst Schirmeier wrote:
[]
>     echo null)
> endef
> 
> My patch proposal (the $(M) one) has the same bug.

Obviously. That was my wrong optimization step.
____

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Oleg Verych]

On Tue, Oct 31, 2006 at 02:14:16AM +0100, Horst Schirmeier wrote:
> On Tue, 31 Oct 2006, Andi Kleen wrote:
> > 
> > > The problem is, this brings us back to the problem where this whole
> > > patch orgy began: Gentoo Portage sandbox violations when writing (the
> > > null symlink) to the kernel tree when building external modules. What
> > > about using $(M) as a base directory if it is defined?
> > 
> > I think Jan's $(objdir)/.tmp proposal would be cleanest. Just someone
> > has to implement it :)
> > 
> > -Andi

$(objtree) here,

> I'm not sure what you mean by $(objdir); I just got something to work
> which creates the /dev/null symlink in a (newly created if necessary)
> directory named

$(objtree) is a directory for all possible outputs of the build precess,
it's set up by `O=' or `KBUILD_OUTPUT', and this is *not* output for ready
external modules `$(M)'. Try to play with this, please.

I'm looking for Sam to say something, if we must go further with this.
____

Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch

[Jan Peter den Heijer]

How about using this:

ASTMP := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)astest$$$$.out

This is also used in the Makefile in the source tree top-level
directory (see line 332)
If KBUILD_EXTMOD is used, temp files are created in the module's
source directory, otherwise in the kernel source top-level directory

Jan Peter

kbuild-mm: $(objtree)/knull vs mktemp (was Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch)

[Oleg Verych]

On Tue, Oct 31, 2006 at 01:27:57AM +0100, Horst Schirmeier wrote:
> # Immortal knull for mortals and roots
> define knull
>   $(shell \
>     if test ! -L knull; \
>       then rm -f knull; ln -s /dev/null knull; \
>     fi; \
>     echo knull)
> endef

So, i think this is much better than mktemp and friends.
Current -mm have +4 temp files after every make help, make, make something.

I'm steel looking forward for comments from (busy) developers, like Sam.

Now i have my laptop back and i can finish this up. Hm?
____

kbuild: O= with M= (Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch)

[Oleg Verych]

On Tue, Oct 31, 2006 at 02:51:36PM +0100, olecom wrote:
[]
> On Tue, Oct 31, 2006 at 02:14:16AM +0100, Horst Schirmeier wrote:
[]
> > I'm not sure what you mean by $(objdir); I just got something to work
> > which creates the /dev/null symlink in a (newly created if necessary)
> > directory named
> 
> $(objtree) is a directory for all possible outputs of the build precess,
> it's set up by `O=' or `KBUILD_OUTPUT', and this is *not* output for ready
> external modules `$(M)'. Try to play with this, please.

And for me, they are *not* working together:

,--[shell]--
|olecom@deen:/tmp/linux-source-2.6.18$ make clean
|olecom@deen:/tmp/linux-source-2.6.18$ make M=$a
|  LD      /mnt/work/app-src-build/kernel.org/_work/ti_usb/built-in.o
|  CC [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.o
|  Building modules, stage 2.
|  MODPOST
|  CC      /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.mod.o
|  LD [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.ko
|olecom@deen:/tmp/linux-source-2.6.18$
|olecom@deen:/tmp/linux-source-2.6.18$ make clean
|olecom@deen:/tmp/linux-source-2.6.18$ make O=/tmp/_build-2.6/ M=$a
|  CC [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.o
|  Building modules, stage 2.
|  MODPOST
|/bin/sh: scripts/mod/modpost: not found
|make[2]: *** [__modpost] Error 127
|make[1]: *** [modules] Error 2
|make: *** [_all] Error 2
|olecom@deen:/tmp/linux-source-2.6.18$ make clean
|olecom@deen:/tmp/linux-source-2.6.18$ make M=$a
|  CC [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.o
|  Building modules, stage 2.
|  MODPOST
|  LD [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.ko
|olecom@deen:/tmp/linux-source-2.6.18$
`--

I'm using 'O=' as good way to have clean kernel source directory,
regardless of any "ignore files" policy. And it seems, must be fixed.

> I'm looking for Sam to say something, if we must go further with this.
> ____
____

[fix, rfc] kbuild: O= with M= (Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch)

[Oleg Verych]

On 2006-11-17, Oleg Verych wrote:
> On Tue, Oct 31, 2006 at 02:51:36PM +0100, olecom wrote:
> []
>> On Tue, Oct 31, 2006 at 02:14:16AM +0100, Horst Schirmeier wrote:
> []
>> > I'm not sure what you mean by $(objdir); I just got something to work
>> > which creates the /dev/null symlink in a (newly created if necessary)
>> > directory named
>> 
>> $(objtree) is a directory for all possible outputs of the build precess,
>> it's set up by `O=' or `KBUILD_OUTPUT', and this is *not* output for ready
>> external modules `$(M)'. Try to play with this, please.
>
> And for me, they are *not* working together:

It works with this:

Proposed-by: me

--- linux-2.6.20-rc5/scripts/Makefile.modpost.orig	2007-01-12 19:54:26.000000000 +0100
+++ linux-2.6.20-rc5/scripts/Makefile.modpost	2007-01-23 08:23:51.583426500 +0100
@@ -58,5 +58,5 @@
 #  Includes step 3,4
 quiet_cmd_modpost = MODPOST $(words $(filter-out vmlinux FORCE, $^)) modules
-      cmd_modpost = scripts/mod/modpost            \
+      cmd_modpost = $(objtree)/scripts/mod/modpost \
         $(if $(CONFIG_MODVERSIONS),-m)             \
 	$(if $(CONFIG_MODULE_SRCVERSION_ALL),-a,)  \
>> ____
> ____
____

[patch] kbuild: improving option checking (Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch)

[Oleg Verych]

Hallo. Tmpfiles, root users, external mod-builds again.

On Tue, Oct 31, 2006 at 02:51:36PM +0100, olecom wrote:
> On Tue, Oct 31, 2006 at 02:14:16AM +0100, Horst Schirmeier wrote:
> > On Tue, 31 Oct 2006, Andi Kleen wrote:
> > > 
> > > > The problem is, this brings us back to the problem where this whole
> > > > patch orgy began: Gentoo Portage sandbox violations when writing (the
> > > > null symlink) to the kernel tree when building external modules. What
> > > > about using $(M) as a base directory if it is defined?
> > > 
> > > I think Jan's $(objdir)/.tmp proposal would be cleanest. Just someone
> > > has to implement it :)
> > > 
> > > -Andi
> 
> $(objtree) here,
> 
> > I'm not sure what you mean by $(objdir); I just got something to work
> > which creates the /dev/null symlink in a (newly created if necessary)
> > directory named
> 
> $(objtree) is a directory for all possible outputs of the build precess,
> it's set up by `O=' or `KBUILD_OUTPUT', and this is *not* output for ready
> external modules `$(M)'. Try to play with this, please.

Kind of fix has finally landed. Instead for `O=/$dir' a patch...

Anyway i whould like propose my solution of:
-- external modules build without KBUILD_OUTPUT set;
-- /dev/null, GNU binutils and root users;
-- beauty;

For external modules, there must be information after
`make modules_prepare' in shipped linux-sources. Any build output is
put in $(objtree), and i don't understand why you don't using that.
Please, *try* `make O=/tmp/build M=/usr/local/src/nvatia'. Thank you.

As some kind of buga-feature, "null" isn't in any clean/mrproper
target (for a while ;).

-*- patch -*-
kbuild: improving option checking

 GNU binutils, root users, tmpfiles, external modules ro builds must
 be fixed to do the right thing now.

 In "safe" environment new /dev/null replacement may be used as simply as
 `echo > null', `gcc -o null'. In aggressive starting with $(null) is
 recommended.

 Feature: file $(objtree)/null isn't in any "clear" target (yet).

Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Oleg Verych <olecom@flower.upol.cz>
---
-o--=O`C
 #oo'L O
<___=E M

--- linux~2.6.20-rc5/scripts/Kbuild.include~blackhole-4-tmpfiles	2007-01-12 19:54:26.000000000 +0100
+++ linux~2.6.20-rc5/scripts/Kbuild.include	2007-01-24 09:19:01.386426000 +0100
@@ -2,5 +2,5 @@
 # kbuild: Generic definitions
 
-# Convinient variables
+# Convinient constants
 comma   := ,
 squote  := '
@@ -8,4 +8,7 @@
 space   := $(empty) $(empty)
 
+# Immortal black-hole for mortals and roots
+null = $(shell test -L null || (rm -f null; ln -s /dev/null null); echo null)
+
 ###
 # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
@@ -57,33 +60,43 @@
 # See documentation in Documentation/kbuild/makefiles.txt
 
-# output directory for tests below
-TMPOUT := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/)
-
 # as-option
 # Usage: cflags-y += $(call as-option, -Wa$(comma)-isa=foo,)
-
-as-option = $(shell if $(CC) $(CFLAGS) $(1) -Wa,-Z -c -o /dev/null \
-	     -xassembler /dev/null > /dev/null 2>&1; then echo "$(1)"; \
-	     else echo "$(2)"; fi ;)
+define as-option
+  $(shell
+    if $(CC) $(CFLAGS) $(1) -c -o $(null) -xassembler null >null 2>&1; \
+      then echo $(1); \
+      else echo $(2); \
+    fi)
+endef
 
 # as-instr
 # Usage: cflags-y += $(call as-instr, instr, option1, option2)
-
-as-instr = $(shell if echo -e "$(1)" | \
-		      $(CC) $(AFLAGS) -c -xassembler - \
-			    -o $(TMPOUT)astest$$$$.out > /dev/null 2>&1; \
-		   then rm $(TMPOUT)astest$$$$.out; echo "$(2)"; \
-		   else echo "$(3)"; fi)
+define as-instr
+  $(shell \
+    if printf "$(1)" | $(AS) >$(null) 2>&1 -W -o null; \
+      then echo "$(2)"; \
+      else echo "$(3)"; \
+    fi)
+endef
 
 # cc-option
 # Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
-
-cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
-             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
+define cc-option
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -S -o $(null) -xc null >null 2>&1; \
+      then echo "$(1)"; \
+      else echo "$(2)"; \
+    fi)
+endef
 
 # cc-option-yn
 # Usage: flag := $(call cc-option-yn, -march=winchip-c6)
-cc-option-yn = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
-                > /dev/null 2>&1; then echo "y"; else echo "n"; fi;)
+define cc-option-yn
+  $(shell \
+    if $(CC) $(CFLAGS) $(1) -S -o $(null) -xc null >null 2>&1; \
+      then echo "y"; \
+      else echo "n"; \
+    fi)
+endef
 
 # cc-option-align
@@ -103,8 +116,11 @@
 # ld-option
 # Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
-ld-option = $(shell if $(CC) $(1) -nostdlib -xc /dev/null \
-			     -o $(TMPOUT)ldtest$$$$.out > /dev/null 2>&1; \
-             then rm $(TMPOUT)ldtest$$$$.out; echo "$(1)"; \
-             else echo "$(2)"; fi)
+define ld-option
+  $(shell \
+    if $(CC) $(1) -nostdlib -o $(null) -xc null >null 2>&1; \
+      then echo "$(1)"; \
+      else echo "$(2)"; \
+    fi)
+endef
 
 ###
@@ -116,4 +132,5 @@
 # Prefix -I with $(srctree) if it is not an absolute path
 addtree = $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1)
+
 # Find all -I options and call addtree
 flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
@@ -126,5 +143,5 @@
 
 ###
-# if_changed      - execute command if any prerequisite is newer than 
+# if_changed      - execute command if any prerequisite is newer than
 #                   target, or command line has changed
 # if_changed_dep  - as if_changed, but uses fixdep to reveal dependencies

Re: [patch] kbuild: improving option checking (Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch)

[Randy Dunlap]

On Wed, 24 Jan 2007 08:54:30 +0000 Oleg Verych wrote:

> Hallo. Tmpfiles, root users, external mod-builds again.
> 
> Kind of fix has finally landed. Instead for `O=/$dir' a patch...
> 
> Anyway i whould like propose my solution of:
> -- external modules build without KBUILD_OUTPUT set;
> -- /dev/null, GNU binutils and root users;
> -- beauty;
> ---
> 
> --- linux~2.6.20-rc5/scripts/Kbuild.include~blackhole-4-tmpfiles	2007-01-12 19:54:26.000000000 +0100
> +++ linux~2.6.20-rc5/scripts/Kbuild.include	2007-01-24 09:19:01.386426000 +0100
> @@ -2,5 +2,5 @@
>  # kbuild: Generic definitions
>  
> -# Convinient variables
> +# Convinient constants

     Convenient

---
~Randy

[patch] spell 4 kbuild: improving option checking

[Oleg Verych]

Signed-off-by: Oleg Verych <olecom@flower.upol.cz>

--- linux~2.6.20-rc5/scripts/Kbuild.include~	2007-01-24 09:19:01.386426000 +0100
+++ linux~2.6.20-rc5/scripts/Kbuild.include	2007-01-24 20:07:11.152820000 +0100
@@ -2,5 +2,5 @@
 # kbuild: Generic definitions
 
-# Convinient constants
+# Convenient constants
 comma   := ,
 squote  := '
@@ -171,5 +171,5 @@
 any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
 
-# Execute command if command has changed or prerequisitei(s) are updated
+# Execute command if command has changed or prerequisite(s) are updated
 #
 if_changed = $(if $(strip $(any-prereq) $(arg-check)),                       \
@@ -188,5 +188,5 @@
 
 # Usage: $(call if_changed_rule,foo)
-# will check if $(cmd_foo) changed, or any of the prequisites changed,
+# will check if $(cmd_foo) changed, or any of the prerequisites changed,
 # and if so will execute $(rule_foo)
 if_changed_rule = $(if $(strip $(any-prereq) $(arg-check) ),                 \
@@ -233,2 +233,4 @@
 echo-why = $(call escsq, $(strip $(why)))
 endif
+
+ LocalWords:  prequisites