[PATCH] perf: Properly align symbol_conf.priv_size

[PATCH] perf: Properly align symbol_conf.priv_size

[David Miller]

If symbol_conf.priv_size is not a multiple of "sizeof(u64)" we'll bus
error on sparc64 in symbol__new because the "struct symbol *" pointer
is computed by adding symbol_conf.priv_size to the memory allocated.

We cannot isloate the fix to symbol__new and symbol__delete since the
private area is computed by subtracting the priv_size value from a
"struct symbol" pointer, so then the private area can still be
potentially unaligned.

So, simply align the symbol_conf.priv_size value in symbol__init()

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 17df793..76c09099 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -2403,6 +2403,8 @@ int symbol__init(void)
 	if (symbol_conf.initialized)
 		return 0;
 
+	symbol_conf.priv_size = ALIGN(symbol_conf.priv_size, sizeof(u64));
+
 	elf_version(EV_CURRENT);
 	if (symbol_conf.sort_by_name)
 		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -

Re: [PATCH] perf: Properly align symbol_conf.priv_size

[Arnaldo Carvalho de Melo]

Em Mon, Mar 28, 2011 at 05:58:49PM -0700, David Miller escreveu:
> 
> If symbol_conf.priv_size is not a multiple of "sizeof(u64)" we'll bus
> error on sparc64 in symbol__new because the "struct symbol *" pointer
> is computed by adding symbol_conf.priv_size to the memory allocated.
> 
> We cannot isloate the fix to symbol__new and symbol__delete since the
> private area is computed by subtracting the priv_size value from a
> "struct symbol" pointer, so then the private area can still be
> potentially unaligned.

That is a clever area, aka something that needs some sanitization,
container_of use possibilities...
attempt-possible-to-become-some-sort-of-progress. :-\

Rusty willing, vowel-optmz+=blts words to trow at that...
 
> So, simply align the symbol_conf.priv_size value in symbol__init()
> 
> Signed-off-by: David S. Miller <davem@davemloft.net>
> 
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 17df793..76c09099 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -2403,6 +2403,8 @@ int symbol__init(void)
>  	if (symbol_conf.initialized)
>  		return 0;
>  
> +	symbol_conf.priv_size = ALIGN(symbol_conf.priv_size, sizeof(u64));
> +
>  	elf_version(EV_CURRENT);
>  	if (symbol_conf.sort_by_name)
>  		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -

[tip:perf/urgent] perf symbols: Properly align symbol_conf.priv_size

[tip-bot for David S. Miller]

Commit-ID:  4d439517561d009e170e2fe20be1ba25e19abe75
Gitweb:     http://git.kernel.org/tip/4d439517561d009e170e2fe20be1ba25e19abe75
Author:     David S. Miller <davem@davemloft.net>
AuthorDate: Tue, 29 Mar 2011 14:18:39 -0300
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 29 Mar 2011 14:18:39 -0300

perf symbols: Properly align symbol_conf.priv_size

If symbol_conf.priv_size is not a multiple of "sizeof(u64)" we'll bus
error on sparc64 in symbol__new because the "struct symbol *" pointer
is computed by adding symbol_conf.priv_size to the memory allocated.

We cannot isolate the fix to symbol__new and symbol__delete since the
private area is computed by subtracting the priv_size value from a
"struct symbol" pointer, so then the private area can still be
potentially unaligned.

So, simply align the symbol_conf.priv_size value in symbol__init()

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20110328.175849.112593455.davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/symbol.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 8f73907..f06c10f 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -2406,6 +2406,8 @@ int symbol__init(void)
 	if (symbol_conf.initialized)
 		return 0;
 
+	symbol_conf.priv_size = ALIGN(symbol_conf.priv_size, sizeof(u64));
+
 	elf_version(EV_CURRENT);
 	if (symbol_conf.sort_by_name)
 		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -