From: Arnd Bergmann <arnd@arndb.de>
To: Borislav Petkov <bp@suse.de>
Cc: Lianbo Jiang <lijiang@redhat.com>,
Alexey Dobriyan <adobriyan@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] kdump, proc/vmcore: fix building without CONFIG_ARCH_HAS_MEM_ENCRYPT
Date: Wed, 10 Oct 2018 16:45:24 +0200 [thread overview]
Message-ID: <CAK8P3a1qzSjt5jPyf7HT-6aJLJdL_ON07y0H+jjy58gKGxdm4A@mail.gmail.com> (raw)
In-Reply-To: <20181010144026.GB5924@zn.tnic>
On 10/10/18, Borislav Petkov <bp@suse.de> 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 <arnd@arndb.de>
>> ---
>> 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
prev parent reply other threads:[~2018-10-10 22:07 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-10 14:32 [PATCH] kdump, proc/vmcore: fix building without CONFIG_ARCH_HAS_MEM_ENCRYPT Arnd Bergmann
2018-10-10 14:40 ` Borislav Petkov
2018-10-10 14:45 ` Arnd Bergmann [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAK8P3a1qzSjt5jPyf7HT-6aJLJdL_ON07y0H+jjy58gKGxdm4A@mail.gmail.com \
--to=arnd@arndb.de \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=bp@suse.de \
--cc=lijiang@redhat.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).