stable.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: <gregkh@linuxfoundation.org>
To: chuhu@redhat.com, gregkh@linuxfoundation.org, tglx@linutronix.de
Cc: <stable@vger.kernel.org>, <stable-commits@vger.kernel.org>
Subject: Patch "x86/idt: Load idt early in start_secondary" has been added to the 4.14-stable tree
Date: Mon, 11 Dec 2017 22:54:15 +0100	[thread overview]
Message-ID: <1513029255243213@kroah.com> (raw)


This is a note to let you know that I've just added the patch titled

    x86/idt: Load idt early in start_secondary

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-idt-load-idt-early-in-start_secondary.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 55d2d0ad2fb4325f615d1950486fbc5e6fba1769 Mon Sep 17 00:00:00 2001
From: Chunyu Hu <chuhu@redhat.com>
Date: Mon, 27 Nov 2017 22:21:39 +0800
Subject: x86/idt: Load idt early in start_secondary

From: Chunyu Hu <chuhu@redhat.com>

commit 55d2d0ad2fb4325f615d1950486fbc5e6fba1769 upstream.

On a secondary, idt is first loaded in cpu_init() with load_current_idt(),
i.e. no exceptions can be handled before that point.

The conversion of WARN() to use UD requires the IDT being loaded earlier as
any warning between start_secondary() and load_curren_idt() in cpu_init()
will result in an unhandled @UD exception and therefore fail the bringup of
the CPU.

Install the IDT handlers right in start_secondary() before calling cpu_init().

[ tglx: Massaged changelog ]

Fixes: 9a93848fe787 ("x86/debug: Implement __WARN() using UD0")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: rostedt@goodmis.org
Cc: luto@kernel.org
Link: https://lkml.kernel.org/r/1511792499-4073-1-git-send-email-chuhu@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/kernel/smpboot.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -239,7 +239,7 @@ static void notrace start_secondary(void
 	load_cr3(swapper_pg_dir);
 	__flush_tlb_all();
 #endif
-
+	load_current_idt();
 	cpu_init();
 	x86_cpuinit.early_percpu_clock_init();
 	preempt_disable();


Patches currently in stable-queue which might be from chuhu@redhat.com are

queue-4.14/x86-idt-load-idt-early-in-start_secondary.patch

                 reply	other threads:[~2017-12-11 21:56 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=1513029255243213@kroah.com \
    --to=gregkh@linuxfoundation.org \
    --cc=chuhu@redhat.com \
    --cc=stable-commits@vger.kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=tglx@linutronix.de \
    /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).