Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933669Ab3JOVEi (ORCPT ); Tue, 15 Oct 2013 17:04:38 -0400 Received: from mail-qa0-f46.google.com ([209.85.216.46]:61735 "EHLO mail-qa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933181Ab3JOVEg (ORCPT ); Tue, 15 Oct 2013 17:04:36 -0400 From: David Long To: linux-arm-kernel@lists.infradead.org Cc: Rabin Vincent , "Jon Medhurst (Tixy)" , Oleg Nesterov , Srikar Dronamraju , Ingo Molnar , linux-kernel@vger.kernel.org Subject: [PATCH v2 03/13] uprobes: allow arch access to xol slot Date: Tue, 15 Oct 2013 17:04:18 -0400 Message-Id: <1381871068-27660-4-git-send-email-dave.long@linaro.org> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1381871068-27660-1-git-send-email-dave.long@linaro.org> References: <1381871068-27660-1-git-send-email-dave.long@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2589 Lines: 69 From: "David A. Long" Allow arches to customize how the instruction is filled into the xol slot. ARM will use this to insert an undefined instruction after the real instruction in order to simulate a single step of the instruction without hardware support. Signed-off-by: Rabin Vincent Signed-off-by: David A. Long --- include/linux/uprobes.h | 1 + kernel/events/uprobes.c | 10 +++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 80116c9..2556ab6 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -134,6 +134,7 @@ extern int arch_uprobe_exception_notify(struct notifier_block *self, unsigned l extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs); extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs); extern bool __weak arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs); +extern void __weak arch_uprobe_xol_copy(struct arch_uprobe *auprobe, void *vaddr); #else /* !CONFIG_UPROBES */ struct uprobes_state { }; diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 3955172..22d0121 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1238,6 +1238,11 @@ static unsigned long xol_take_insn_slot(struct xol_area *area) return slot_addr; } +void __weak arch_uprobe_xol_copy(struct arch_uprobe *auprobe, void *vaddr) +{ + memcpy(vaddr, auprobe->insn, MAX_UINSN_BYTES); +} + /* * xol_get_insn_slot - allocate a slot for xol. * Returns the allocated slot address or 0. @@ -1246,6 +1251,7 @@ static unsigned long xol_get_insn_slot(struct uprobe *uprobe) { struct xol_area *area; unsigned long xol_vaddr; + void *kaddr; area = get_xol_area(); if (!area) @@ -1256,7 +1262,9 @@ static unsigned long xol_get_insn_slot(struct uprobe *uprobe) return 0; /* Initialize the slot */ - copy_to_page(area->page, xol_vaddr, uprobe->arch.insn, MAX_UINSN_BYTES); + kaddr = kmap_atomic(area->page); + arch_uprobe_xol_copy(&uprobe->arch, kaddr + (xol_vaddr & ~PAGE_MASK)); + kunmap_atomic(kaddr); /* * We probably need flush_icache_user_range() but it needs vma. * This should work on supported architectures too. -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/