Dave Jones 612c353178 selinux: conditionally reschedule in mls_convert_context while loading selinux policy ... On a slow machine (with debugging enabled), upgrading selinux policy may take a considerable amount of time. Long enough that the softlockup detector gets triggered. The backtrace looks like this.. > BUG: soft lockup - CPU#2 stuck for 23s! [load_policy:19045] > Call Trace: > [<ffffffff81221ddf>] symcmp+0xf/0x20 > [<ffffffff81221c27>] hashtab_search+0x47/0x80 > [<ffffffff8122e96c>] mls_convert_context+0xdc/0x1c0 > [<ffffffff812294e8>] convert_context+0x378/0x460 > [<ffffffff81229170>] ? security_context_to_sid_core+0x240/0x240 > [<ffffffff812221b5>] sidtab_map+0x45/0x80 > [<ffffffff8122bb9f>] security_load_policy+0x3ff/0x580 > [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100 > [<ffffffff810786dd>] ? sched_clock_local+0x1d/0x80 > [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100 > [<ffffffff8103096a>] ? __change_page_attr_set_clr+0x82a/0xa50 > [<ffffffff810786dd>] ? sched_clock_local+0x1d/0x80 > [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100 > [<ffffffff8103096a>] ? __change_page_attr_set_clr+0x82a/0xa50 > [<ffffffff810788a8>] ? sched_clock_cpu+0xa8/0x100 > [<ffffffff81534ddc>] ? retint_restore_args+0xe/0xe > [<ffffffff8109c82d>] ? trace_hardirqs_on_caller+0xfd/0x1c0 > [<ffffffff81279a2e>] ? trace_hardirqs_on_thunk+0x3a/0x3f > [<ffffffff810d28a8>] ? rcu_irq_exit+0x68/0xb0 > [<ffffffff81534ddc>] ? retint_restore_args+0xe/0xe > [<ffffffff8121e947>] sel_write_load+0xa7/0x770 > [<ffffffff81139633>] ? vfs_write+0x1c3/0x200 > [<ffffffff81210e8e>] ? security_file_permission+0x1e/0xa0 > [<ffffffff8113952b>] vfs_write+0xbb/0x200 > [<ffffffff811581c7>] ? fget_light+0x397/0x4b0 > [<ffffffff81139c27>] SyS_write+0x47/0xa0 > [<ffffffff8153bde4>] tracesys+0xdd/0xe2 Stephen Smalley suggested: > Maybe put a cond_resched() within the ebitmap_for_each_positive_bit() > loop in mls_convert_context()? That seems to do the trick. Tested by downgrading and re-upgrading selinux-policy-targeted. Signed-off-by: Dave Jones <davej@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <pmoore@redhat.com>		2014-05-15 17:06:14 -04:00
..
avtab.c
avtab.h
conditional.c
conditional.h
constraint.h	SELinux: Update policy version to support constraints info	2013-11-19 17:34:23 -05:00
context.h
ebitmap.c	SELinux: Reduce overhead of mls_level_isvalid() function call	2013-07-25 13:02:18 -04:00
ebitmap.h	SELinux: Increase ebitmap_node size for 64-bit configuration	2013-07-25 13:02:31 -04:00
hashtab.c
hashtab.h
mls_types.h	SELinux: Reduce overhead of mls_level_isvalid() function call	2013-07-25 13:02:18 -04:00
mls.c	selinux: conditionally reschedule in mls_convert_context while loading selinux policy	2014-05-15 17:06:14 -04:00
mls.h
policydb.c	SELinux: bigendian problems with filename trans rules	2014-02-20 12:07:58 -05:00
policydb.h	SELinux: Update policy version to support constraints info	2013-11-19 17:34:23 -05:00
services.c	selinux: add gfp argument to security_xfrm_policy_alloc and fix callers	2014-03-10 08:30:02 +01:00
services.h
sidtab.c
sidtab.h
status.c
symtab.c
symtab.h