From 0fcfe9d95f8bb1d53cf68038f13bc3563020e8cd Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Fri, 11 Sep 2020 14:16:14 +0200 Subject: [PATCH] x86/PV: fold exit paths of ptwr_do_page_fault() One less aspect to keep an eye on for things to stay in sync. Signed-off-by: Jan Beulich Acked-by: Andrew Cooper --- xen/arch/x86/pv/ro-page-fault.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-) diff --git a/xen/arch/x86/pv/ro-page-fault.c b/xen/arch/x86/pv/ro-page-fault.c index 0eedb70002..556ee7ca11 100644 --- a/xen/arch/x86/pv/ro-page-fault.c +++ b/xen/arch/x86/pv/ro-page-fault.c @@ -262,29 +262,23 @@ static int ptwr_do_page_fault(struct x86_emulate_ctxt *ctxt, .pte = pte, }; struct page_info *page; - int rc; + int rc = X86EMUL_UNHANDLEABLE; page = get_page_from_mfn(l1e_get_mfn(pte), current->domain); if ( !page ) return X86EMUL_UNHANDLEABLE; - if ( !page_lock(page) ) + if ( page_lock(page) ) { - put_page(page); - return X86EMUL_UNHANDLEABLE; - } + if ( (page->u.inuse.type_info & PGT_type_mask) == PGT_l1_page_table ) + { + ctxt->data = &ptwr_ctxt; + rc = x86_emulate(ctxt, &ptwr_emulate_ops); + } - if ( (page->u.inuse.type_info & PGT_type_mask) != PGT_l1_page_table ) - { page_unlock(page); - put_page(page); - return X86EMUL_UNHANDLEABLE; } - ctxt->data = &ptwr_ctxt; - rc = x86_emulate(ctxt, &ptwr_emulate_ops); - - page_unlock(page); put_page(page); return rc; -- 2.39.5