From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-f196.google.com ([209.85.160.196]:46904 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726617AbeJJWHz (ORCPT ); Wed, 10 Oct 2018 18:07:55 -0400 MIME-Version: 1.0 In-Reply-To: <20181010144026.GB5924@zn.tnic> References: <20181010143306.2051406-1-arnd@arndb.de> <20181010144026.GB5924@zn.tnic> From: Arnd Bergmann Date: Wed, 10 Oct 2018 16:45:24 +0200 Message-ID: Subject: Re: [PATCH] kdump, proc/vmcore: fix building without CONFIG_ARCH_HAS_MEM_ENCRYPT To: Borislav Petkov Cc: Lianbo Jiang , Alexey Dobriyan , Andrew Morton , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On 10/10/18, Borislav Petkov wrote: > On Wed, Oct 10, 2018 at 04:32:45PM +0200, Arnd Bergmann wrote: >> We get a link failure when calling copy_oldmem_page_encrypted() >> when the compiler fails to do constant-propagation of the >> sme_active() result into read_from_oldmem: >> >> fs/proc/vmcore.o: In function `read_from_oldmem.part.0': >> vmcore.c:(.text+0xb7): undefined reference to >> `copy_oldmem_page_encrypted' >> >> Adding an IS_ENABLED() check means the compiler will always >> know when it cannot be enabled. >> >> Fixes: 992b649a3f01 ("kdump, proc/vmcore: Enable kdumping encrypted memory >> with SME enabled") >> Signed-off-by: Arnd Bergmann >> --- >> There may be a better way of doing this, not sure what kinds >> of assumptions we want to make here. >> --- >> fs/proc/vmcore.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c >> index d469ce9d8c0c..92e1e520a52d 100644 >> --- a/fs/proc/vmcore.c >> +++ b/fs/proc/vmcore.c >> @@ -123,7 +123,9 @@ static ssize_t read_from_oldmem(char *buf, size_t >> count, >> if (pfn_is_ram(pfn) == 0) >> memset(buf, 0, nr_bytes); >> else { >> - if (encrypted) >> + if (IS_ENABLED(CONFIG_X86_64) && >> + IS_ENABLED(CONFIG_ARCH_HAS_MEM_ENCRYPT) && >> + encrypted) >> tmp = copy_oldmem_page_encrypted(pfn, buf, >> nr_bytes, >> offset, >> -- > > Doesn't that fix it? > > https://git.kernel.org/tip/cf089611f4c446285046fcd426d90c18f37d2905 Sorry, my mistake. I noticed this patch was still in my queue and not marked as 'submitted'. I forgot we had already discussed it. Arnd