Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932118AbbGXLxc (ORCPT ); Fri, 24 Jul 2015 07:53:32 -0400 Received: from mail-pa0-f42.google.com ([209.85.220.42]:33096 "EHLO mail-pa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754250AbbGXLxV convert rfc822-to-8bit (ORCPT ); Fri, 24 Jul 2015 07:53:21 -0400 Content-Type: text/plain; charset=gb2312 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2102\)) Subject: Re: [RFC] arm64:use set_fixmap_offset to make it more clear From: yalin wang In-Reply-To: <20150724100724.GA4348@leverpostej> Date: Fri, 24 Jul 2015 19:53:14 +0800 Cc: yalin wang , "lauraa@codeaurora.org" , Marc Zyngier , Catalin Marinas , Punit Agrawal , Will Deacon , "linux-kernel@vger.kernel.org" , "zlim.lnx@gmail.com" , "wcohen@redhat.com" , "linux-arm-kernel@lists.infradead.org" Content-Transfer-Encoding: 8BIT Message-Id: <11F09FCC-E973-44E9-BDBF-88F8F27D4601@gmail.com> References: <20150723130344.GC27052@e104818-lin.cambridge.arm.com> <9E910A45-D4AB-44F6-878F-3CB2372B3660@gmail.com> <20150724095618.GB23074@leverpostej> <20150724100724.GA4348@leverpostej> To: Mark Rutland X-Mailer: Apple Mail (2.2102) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3592 Lines: 85 > ?? 2015??7??24?գ?18:07??Mark Rutland д???? > > On Fri, Jul 24, 2015 at 10:56:18AM +0100, Mark Rutland wrote: >> On Fri, Jul 24, 2015 at 04:56:59AM +0100, yalin wang wrote: >>> >>>> On Jul 23, 2015, at 21:03, Catalin Marinas wrote: >>>> >>>> On Thu, Jul 23, 2015 at 07:45:53PM +0800, yalin wang wrote: >>>>> A little change to patch_map() function, >>>>> use set_fixmap_offset() to make code more clear. >>>>> >>>>> Signed-off-by: yalin wang >>>>> --- >>>>> arch/arm64/kernel/insn.c | 5 ++--- >>>>> 1 file changed, 2 insertions(+), 3 deletions(-) >>>>> >>>>> diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c >>>>> index dd9671c..7dafd5a 100644 >>>>> --- a/arch/arm64/kernel/insn.c >>>>> +++ b/arch/arm64/kernel/insn.c >>>>> @@ -101,9 +101,8 @@ static void __kprobes *patch_map(void *addr, int fixmap) >>>>> return addr; >>>>> >>>>> BUG_ON(!page); >>>>> - set_fixmap(fixmap, page_to_phys(page)); >>>>> - >>>>> - return (void *) (__fix_to_virt(fixmap) + (uintaddr & ~PAGE_MASK)); >>>>> + return (void *)set_fixmap_offset(fixmap, page_to_phys(page) + >>>>> + (addr & ~PAGE_MASK)); >>>> >>>> It looks fine. Do you get any compiler warning for the automatic pointer >>>> to long conversion? You may want to add some explicit casts, otherwise: >>>> >>>> Acked-by: Catalin Marinas >>> i have build it, there is no warning about this change. :) >> >> I see no warnings with defconfig, but there's an (unrelated) set of warnings if >> CONFIG_DEBUG_SET_MODULE_RONX or CONFIG_DEBUG_RODATA are enabled: > > Actually they aren't unrelated after all. the unsigned long addr in > __set_fixmap_offset shadows the void* addr from patch_map making the > types match. > > With a few underscores addrd to __set_fixmap_offset's addr, I get the > following regarding patch_map: > > ---- > In file included from ./arch/arm64/include/asm/fixmap.h:85:0, > from arch/arm64/kernel/insn.c:32: > arch/arm64/kernel/insn.c: In function ??patch_map??: > arch/arm64/kernel/insn.c:105:10: error: invalid operands to binary & (have ??void *?? and ??long unsigned int??) > (addr & ~PAGE_MASK)); > ^ > include/asm-generic/fixmap.h:73:20: note: in definition of macro ??__set_fixmap_offset?? > __set_fixmap(idx, phys, flags); \ > ^ > arch/arm64/kernel/insn.c:104:17: note: in expansion of macro ??set_fixmap_offset?? > return (void *)set_fixmap_offset(fixmap, page_to_phys(page) + > ^ > arch/arm64/kernel/insn.c:105:10: error: invalid operands to binary & (have ??void *?? and ??long unsigned int??) > (addr & ~PAGE_MASK)); > ^ > include/asm-generic/fixmap.h:74:32: note: in definition of macro ??__set_fixmap_offset?? > __addr = fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1)); \ > ^ > arch/arm64/kernel/insn.c:104:17: note: in expansion of macro ??set_fixmap_offset?? > return (void *)set_fixmap_offset(fixmap, page_to_phys(page) + > ^ > make[1]: *** [arch/arm64/kernel/insn.o] Error 1 > make: *** [arch/arm64/kernel/insn.o] Error 2 > ---- > > we need both the cast in patch_map, and an update to __set_fixmap_offset to > prevent the name clash. > > Thanks, > Mark. i see, i will send V2 to solve this. Thanks-- 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/