On Tue, Jan 2, 2018 at 12:42 AM, Sam Ravnborg [off-list ref] wrote:

Hi Anatoly.

On Tue, Jan 02, 2018 at 12:11:49AM +0300, Anatoly Pugachev wrote:

quoted

Hello!

Using latest git kernel (4.15.0-rc6) , getting the following messages
on LDOM/kernel boot:

[    7.693653] Kernel unaligned access at TPC[7496d8] aa_dfa_unpack+0x38/0x580
[    7.693735] Kernel unaligned access at TPC[7496f8] aa_dfa_unpack+0x58/0x580
[    7.693782] Kernel unaligned access at TPC[749708] aa_dfa_unpack+0x68/0x580
[    7.693829] Kernel unaligned access at TPC[74973c] aa_dfa_unpack+0x9c/0x580
[    7.693875] Kernel unaligned access at TPC[749758] aa_dfa_unpack+0xb8/0x580
[    7.697135] audit: type=1400 audit(1514840016.480:2):
apparmor="STATUS" operation="profile_load" profile="unconfined"
name="/usr/sbin/tcpdump" pid=507 comm="apparmor_parser"


Can someone please look, what could cause unaligned access at this
aa_dfa_unpack function/structure ?

A quick guess would be that you are using nulldfa.
And this variable may not be aligned.

Try to check the address of nulldfa_src.

You could also try to force the compiler to align the data
to 8 byte like this (security/apparmor/match.c):

static char nulldfa_src[] = {
        #include "nulldfa.in"
} __aligned(8);                 <= see the added __aligned(8)

This is just from a quick look at things, but please try it to
see if this is the problematic spot.

Sam,

this doesn't work:

$ make
...
  CC      security/apparmor/match.o
In file included from ./include/linux/compiler_types.h:58:0,
                 from ./include/linux/linkage.h:5,
                 from ./include/linux/kernel.h:7,
                 from security/apparmor/match.c:16:
./include/linux/compiler-gcc.h:123:23: error: expected ?,? or ?;?
before ?__attribute__?
 #define __aligned(x)  __attribute__((aligned(x)))
                       ^
security/apparmor/match.c:30:3: note: in expansion of macro ?__aligned?
 } __aligned(8);
   ^~~~~~~~~
scripts/Makefile.build:310: recipe for target 'security/apparmor/match.o' failed

$ git diff

diff --git a/security/apparmor/match.c b/security/apparmor/match.c
index 72c604350e80..8f42ab8fc365 100644
--- a/security/apparmor/match.c
+++ b/security/apparmor/match.c

@@ -27,7 +27,7 @@

 static char nulldfa_src[] = {
        #include "nulldfa.in"
-};
+} __aligned(8);
 struct aa_dfa *nulldfa;

 int aa_setup_dfa_engine(void)

~/linux-2.6$
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