Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753549AbcLMKlE (ORCPT ); Tue, 13 Dec 2016 05:41:04 -0500 Received: from mailapp01.imgtec.com ([195.59.15.196]:63265 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752619AbcLMKlC (ORCPT ); Tue, 13 Dec 2016 05:41:02 -0500 From: Marcin Nowakowski To: CC: , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Victor Kamensky Subject: [PATCH] uprobes: allow for a cache flush after ixol breakpoint creation Date: Tue, 13 Dec 2016 11:40:57 +0100 Message-ID: <1481625657-22850-1-git-send-email-marcin.nowakowski@imgtec.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.80.2.5] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1510 Lines: 39 Commit 72e6ae285a1d ('ARM: 8043/1: uprobes need icache flush after xol write' has introduced an arch-specific method to ensure all caches are flushed appropriately after an instruction is written to an XOL page. However, when the XOL area is created and the out-of-line breakpoint instruction is copied, caches are not flushed at all and stale data may be found in icache. Replace a simple copy_to_page() with arch_uprobe_copy_ixol() to allow the arch to ensure all caches are updated accordingly. This change fixes uprobes on MIPS InterAptiv (tested on Creator Ci40). Signed-off-by: Marcin Nowakowski CC: Peter Zijlstra CC: Ingo Molnar CC: Arnaldo Carvalho de Melo CC: Alexander Shishkin CC: Victor Kamensky --- kernel/events/uprobes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index f9ec9ad..b5916b4 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1194,7 +1194,7 @@ static struct xol_area *__create_xol_area(unsigned long vaddr) /* Reserve the 1st slot for get_trampoline_vaddr() */ set_bit(0, area->bitmap); atomic_set(&area->slot_count, 1); - copy_to_page(area->pages[0], 0, &insn, UPROBE_SWBP_INSN_SIZE); + arch_uprobe_copy_ixol(area->pages[0], 0, &insn, UPROBE_SWBP_INSN_SIZE); if (!xol_add_vma(mm, area)) return area; -- 2.7.4