From 31f688a26d82ce00d1ec7ca9ed17b9914bf5176f Mon Sep 17 00:00:00 2001 From: Konstantin Belousov Date: Wed, 24 Jul 2024 13:17:55 +0300 Subject: [PATCH] rtld: avoid division in __thr_map_stacks_exec() The function is called by rtld with the rtld bind lock write-locked, when fixing the stack permission during dso load. Not every ARMv7 CPU supports the div, which causes the recursive entry into rtld to resolve the __aeabi_uidiv symbol, causing self-lock. Workaround the problem by using roundup2() instead of open-coding less efficient formula. Diagnosed by: mmel Based on submission by: John F Carr Sponsored by: The FreeBSD Foundation MFC after: 1 week --- lib/libthr/thread/thr_stack.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/lib/libthr/thread/thr_stack.c b/lib/libthr/thread/thr_stack.c index f576a2c0410..d249bb5606f 100644 --- a/lib/libthr/thread/thr_stack.c +++ b/lib/libthr/thread/thr_stack.c @@ -126,10 +126,7 @@ static char *last_stack = NULL; static inline size_t round_up(size_t size) { - if (size % _thr_page_size != 0) - size = ((size / _thr_page_size) + 1) * - _thr_page_size; - return size; + return (roundup2(size, _thr_page_size)); } void