From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935872AbYD1S7j (ORCPT ); Mon, 28 Apr 2008 14:59:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935207AbYD1S7K (ORCPT ); Mon, 28 Apr 2008 14:59:10 -0400 Received: from hu-out-0506.google.com ([72.14.214.239]:62721 "EHLO hu-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932602AbYD1S7H (ORCPT ); Mon, 28 Apr 2008 14:59:07 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:in-reply-to:references:x-mailer:mime-version:content-type:content-transfer-encoding:sender; b=m8gDY3qRKsWBDTDYVqbua2Z+nVp7cLS93JlhHE7XWE+Ax/yt2SXkeHojX6ACwrkLjPbNkEkiJYSAC1Vyo9boC1HBmFFYJ9ioxNdS4rbN5aatmVmaiz3fjInRITHXRelhx6kp6R+1HvEZu+xn3+FfhO03AI1QDQc0Iyf47oA2hJY= Date: Mon, 28 Apr 2008 21:58:54 +0300 From: Pekka Paalanen To: linux-kernel@vger.kernel.org Cc: Pekka Paalanen , Ingo Molnar , Christoph Hellwig , Arjan van de Ven , Pavel Roskin , Steven Rostedt , Peter Zijlstra , Andrew Morton Subject: Re: [RFC 1/3] mmiotrace full patch, preview 3 Message-ID: <20080428215854.1047eb5d@daedalus.pq.iki.fi> In-Reply-To: <20080428214504.5c359195@daedalus.pq.iki.fi> References: <20080428214504.5c359195@daedalus.pq.iki.fi> X-Mailer: Claws Mail 3.0.2 (GTK+ 2.12.8; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 28 Apr 2008 21:45:04 +0300 Pekka Paalanen wrote: > Hi all, > > this is the third full mmiotrace patch set for review (a bit late, sorry). > These patches do not apply to any git tree that I know of, but after Ingo > pushes a new version of his sched-devel/latest tree, these patches should > be subtractable from there. ... > This first patch adds the bulk of the new code, only introducing new files. > The second patch establishes the interfaces to the ftrace framework, and > the third patch hooks everything up into the Kbuild system, page fault > handler, and ioremap functions. arch/x86/Kconfig.debug | 28 ++++++++++++++++++++++++++++ arch/x86/mm/Makefile | 5 +++++ arch/x86/mm/fault.c | 13 +++++++++++++ arch/x86/mm/ioremap.c | 9 ++++++++- arch/x86/mm/pageattr.c | 1 + 5 files changed, 55 insertions(+), 1 deletions(-) diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 1f237d2..fb0794e 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -170,6 +170,34 @@ config IOMMU_LEAK Add a simple leak tracer to the IOMMU code. This is useful when you are debugging a buggy device driver that leaks IOMMU mappings. +config MMIOTRACE_HOOKS + bool + +config MMIOTRACE + bool "Memory mapped IO tracing" + depends on DEBUG_KERNEL && PCI + select TRACING + select MMIOTRACE_HOOKS + default y + help + Mmiotrace traces Memory Mapped I/O access and is meant for + debugging and reverse engineering. It is called from the ioremap + implementation and works via page faults. Tracing is disabled by + default and can be enabled at run-time. + + See Documentation/tracers/mmiotrace.txt. + If you are not helping to develop drivers, say N. + +config MMIOTRACE_TEST + tristate "Test module for mmiotrace" + depends on MMIOTRACE && m + help + This is a dumb module for testing mmiotrace. It is very dangerous + as it will write garbage to IO memory starting at a given address. + However, it should be safe to use on e.g. unused portion of VRAM. + + Say N, unless you absolutely know what you are doing. + # # IO delay types: # diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index b7b3e4c..07dab50 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -8,6 +8,11 @@ obj-$(CONFIG_X86_PTDUMP) += dump_pagetables.o obj-$(CONFIG_HIGHMEM) += highmem_32.o +obj-$(CONFIG_MMIOTRACE_HOOKS) += kmmio.o +obj-$(CONFIG_MMIOTRACE) += mmiotrace.o +mmiotrace-y := pf_in.o mmio-mod.o +obj-$(CONFIG_MMIOTRACE_TEST) += testmmiotrace.o + ifeq ($(CONFIG_X86_32),y) obj-$(CONFIG_NUMA) += discontig_32.o else diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 4145597..0440dce 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -51,6 +52,16 @@ #define PF_RSVD (1<<3) #define PF_INSTR (1<<4) +static inline int kmmio_fault(struct pt_regs *regs, unsigned long addr) +{ +#ifdef CONFIG_MMIOTRACE_HOOKS + if (unlikely(is_kmmio_active())) + if (kmmio_handler(regs, addr) == 1) + return -1; +#endif + return 0; +} + static inline int notify_page_fault(struct pt_regs *regs) { #ifdef CONFIG_KPROBES @@ -623,6 +634,8 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) if (notify_page_fault(regs)) return; + if (unlikely(kmmio_fault(regs, address))) + return; /* * We fault-in kernel-space virtual memory on-demand. The diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index d176b23..68b287d 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include @@ -126,6 +127,7 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size, unsigned long new_prot_val; pgprot_t prot; int retval; + void __iomem *ret_addr; /* Don't allow wraparound or zero size */ last_addr = phys_addr + size - 1; @@ -229,7 +231,10 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size, return NULL; } - return (void __iomem *) (vaddr + offset); + ret_addr = (void __iomem *) (vaddr + offset); + mmiotrace_ioremap(phys_addr, size, ret_addr); + + return ret_addr; } /** @@ -306,6 +311,8 @@ void iounmap(volatile void __iomem *addr) addr < phys_to_virt(ISA_END_ADDRESS)) return; + mmiotrace_iounmap(addr); + addr = (volatile void __iomem *) (PAGE_MASK & (unsigned long __force)addr); diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index bd5e05c..099374b 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -227,6 +227,7 @@ pte_t *lookup_address(unsigned long address, unsigned int *level) return pte_offset_kernel(pmd, address); } +EXPORT_SYMBOL_GPL(lookup_address); /* * Set the new pmd in all the pgds we know about: