From 955e304f6fc1703edafed69b299a8ca39233f865 Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Thu, 28 Dec 2017 13:08:09 -0500 Subject: [PATCH] linux-user: init_guest_commpage: Add a comment about size check Signed-off-by: Luke Shumaker Message-Id: <20171228180814.9749-7-lukeshu@lukeshu.com> Reviewed-by: Peter Maydell Signed-off-by: Laurent Vivier --- linux-user/elfload.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/linux-user/elfload.c b/linux-user/elfload.c index 653157876c..8699f430b1 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -374,6 +374,11 @@ static int init_guest_commpage(unsigned long guest_base, /* If the commpage lies within the already allocated guest space, * then there is no way we can allocate it. + * + * You may be thinking that that this check is redundant because + * we already validated the guest size against MAX_RESERVED_VA; + * but if qemu_host_page_mask is unusually large, then + * test_page_addr may be lower. */ if (test_page_addr >= guest_base && test_page_addr < (guest_base + guest_size)) { -- 2.11.0