lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Tue, 11 May 2021 00:27:51 +0900
From:   Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
To:     Yury Norov <yury.norov@...il.com>, linux-kernel@...r.kernel.org,
        Andrew Morton <akpm@...ux-foundation.org>,
        Rasmus Villemoes <linux@...musvillemoes.dk>
Cc:     linux-m68k@...ts.linux-m68k.org, linux-arch@...r.kernel.org,
        linux-sh@...r.kernel.org, Alexey Klimov <aklimov@...hat.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Arnd Bergmann <arnd@...db.de>, David Sterba <dsterba@...e.com>,
        Dennis Zhou <dennis@...nel.org>,
        Geert Uytterhoeven <geert@...ux-m68k.org>,
        Jianpeng Ma <jianpeng.ma@...el.com>,
        Joe Perches <joe@...ches.com>,
        John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de>,
        Josh Poimboeuf <jpoimboe@...hat.com>,
        Rich Felker <dalias@...c.org>,
        Stefano Brivio <sbrivio@...hat.com>,
        Wei Yang <richard.weiyang@...ux.alibaba.com>,
        Wolfram Sang <wsa+renesas@...g-engineering.com>,
        Yoshinori Sato <ysato@...rs.sourceforge.jp>
Subject: Re: [PATCH 11/12] tools: sync lib/find_bit implementation

Commit eaae7841ba83bb42 ("tools: sync lib/find_bit implementation") broke
build of 5.13-rc1 using gcc (GCC) 8.3.1 20190311 (Red Hat 8.3.1-3).

  DESCEND  objtool
  CC       /usr/src/linux/tools/objtool/exec-cmd.o
  CC       /usr/src/linux/tools/objtool/help.o
  CC       /usr/src/linux/tools/objtool/pager.o
  CC       /usr/src/linux/tools/objtool/parse-options.o
  CC       /usr/src/linux/tools/objtool/run-command.o
  CC       /usr/src/linux/tools/objtool/sigchain.o
  CC       /usr/src/linux/tools/objtool/subcmd-config.o
  LD       /usr/src/linux/tools/objtool/libsubcmd-in.o
  AR       /usr/src/linux/tools/objtool/libsubcmd.a
  CC       /usr/src/linux/tools/objtool/arch/x86/special.o
In file included from /usr/src/linux/tools/include/linux/kernel.h:8:0,
                 from /usr/src/linux/tools/include/linux/list.h:7,
                 from /usr/src/linux/tools/objtool/include/objtool/arch.h:10,
                 from /usr/src/linux/tools/objtool/include/objtool/check.h:11,
                 from /usr/src/linux/tools/objtool/include/objtool/special.h:10,
                 from arch/x86/special.c:4:
/usr/src/linux/tools/include/asm-generic/bitops/find.h: In function 'find_next_bit':
/usr/src/linux/tools/include/linux/bits.h:24:21: error: first argument to '__builtin_choose_expr' not a constant
  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
                     ^
/usr/src/linux/tools/include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
 #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
                                                              ^
/usr/src/linux/tools/include/linux/bits.h:38:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
   ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h:32:17: note: in expansion of macro 'GENMASK'
   val = *addr & GENMASK(size - 1, offset);
                 ^
/usr/src/linux/tools/include/linux/build_bug.h:16:51: error: bit-field '<anonymous>' width not an integer constant
 #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
                                                   ^
/usr/src/linux/tools/include/linux/bits.h:24:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
   ^
/usr/src/linux/tools/include/linux/bits.h:38:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
   ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h:32:17: note: in expansion of macro 'GENMASK'
   val = *addr & GENMASK(size - 1, offset);
                 ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h: In function 'find_next_and_bit':
/usr/src/linux/tools/include/linux/bits.h:24:21: error: first argument to '__builtin_choose_expr' not a constant
  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
                     ^
/usr/src/linux/tools/include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
 #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
                                                              ^
/usr/src/linux/tools/include/linux/bits.h:38:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
   ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h:62:27: note: in expansion of macro 'GENMASK'
   val = *addr1 & *addr2 & GENMASK(size - 1, offset);
                           ^
/usr/src/linux/tools/include/linux/build_bug.h:16:51: error: bit-field '<anonymous>' width not an integer constant
 #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
                                                   ^
/usr/src/linux/tools/include/linux/bits.h:24:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
   ^
/usr/src/linux/tools/include/linux/bits.h:38:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
   ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h:62:27: note: in expansion of macro 'GENMASK'
   val = *addr1 & *addr2 & GENMASK(size - 1, offset);
                           ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h: In function 'find_next_zero_bit':
/usr/src/linux/tools/include/linux/bits.h:24:21: error: first argument to '__builtin_choose_expr' not a constant
  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
                     ^
/usr/src/linux/tools/include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
 #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
                                                              ^
/usr/src/linux/tools/include/linux/bits.h:38:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
   ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h:90:18: note: in expansion of macro 'GENMASK'
   val = *addr | ~GENMASK(size - 1, offset);
                  ^
/usr/src/linux/tools/include/linux/build_bug.h:16:51: error: bit-field '<anonymous>' width not an integer constant
 #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
                                                   ^
/usr/src/linux/tools/include/linux/bits.h:24:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
  (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
   ^
/usr/src/linux/tools/include/linux/bits.h:38:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
   ^
/usr/src/linux/tools/include/asm-generic/bitops/find.h:90:18: note: in expansion of macro 'GENMASK'
   val = *addr | ~GENMASK(size - 1, offset);
                  ^
make[5]: *** [/usr/src/linux/tools/objtool/arch/x86/special.o] Error 1
make[4]: *** [arch/x86] Error 2
make[3]: *** [/usr/src/linux/tools/objtool/objtool-in.o] Error 2
make[2]: *** [objtool] Error 2
make[1]: *** [tools/objtool] Error 2
make: *** [__sub-make] Error 2



Applying below diff seems to solve the build failure.
Do we need to use BUILD_BUG_ON_ZERO() here?

diff --git a/tools/include/linux/bits.h b/tools/include/linux/bits.h
index 7f475d59a097..0aba9294f29d 100644
--- a/tools/include/linux/bits.h
+++ b/tools/include/linux/bits.h
@@ -21,8 +21,7 @@
 #if !defined(__ASSEMBLY__)
 #include <linux/build_bug.h>
 #define GENMASK_INPUT_CHECK(h, l) \
-	(BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
-		__builtin_constant_p((l) > (h)), (l) > (h), 0)))
+	({ BUILD_BUG_ON(__builtin_constant_p((l) > (h)) && ((l) > (h))); 0; })
 #else
 /*
  * BUILD_BUG_ON_ZERO is not available in h files included from asm files,



Also, why the fast path of find_*_bit() functions does not check
__builtin_constant_p(offset) as well as small_const_nbits(size), for the fast
path fails to catch BUILD_BUG_ON_ZERO() when offset argument is not a constant.

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ