xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Andy Lutomirski <luto@amacapital.net>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: KVM list <kvm@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>, X86 ML <x86@kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	xen-devel <Xen-devel@lists.xen.org>,
	Borislav Petkov <bp@alien8.de>, Andy Lutomirski <luto@kernel.org>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Arjan van de Ven <arjan@linux.intel.com>
Subject: Re: [PATCH v4 2/5] x86/msr: Carry on after a non-"safe" MSR access fails without !panic_on_oops
Date: Mon, 14 Mar 2016 11:48:47 -0700	[thread overview]
Message-ID: <CALCETrWxSBwwFTFsRoR_9AVBoC0iJ1pdWwOq_cnFf3NHUpG4QA__4380.79764503545$1457981441$gmane$org@mail.gmail.com> (raw)
In-Reply-To: <CA+55aFy2dNgBJwjd+fRUYQf9OxqGkkcjUEarv+o3QSFTJ6+gJQ@mail.gmail.com>

On Mon, Mar 14, 2016 at 11:40 AM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Mon, Mar 14, 2016 at 11:24 AM, Andy Lutomirski <luto@amacapital.net> wrote:
>>
>> The code in my queue is, literally:
>>
>> bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup,
>>                  struct pt_regs *regs, int trapnr)
>> {
>>     WARN_ONCE(1, "unchecked MSR access error: RDMSR from 0x%x",
>>           (unsigned int)regs->cx);
>>
>>     /* Pretend that the read succeeded and returned 0. */
>>     regs->ip = ex_fixup_addr(fixup);
>>     regs->ax = 0;
>>     regs->dx = 0;
>>     return true;
>> }
>> EXPORT_SYMBOL(ex_handler_rdmsr_unsafe);
>
> I guess I can live with this, as long as we also extend the
> early-fault handling to work with the special exception handlers.

OK, will do.  I need to rewrork the early IDT code a bit so it
generates a real pt_regs layout, but that's arguably a cleanup anyway.

--Andy

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

  parent reply	other threads:[~2016-03-14 18:48 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <cover.1457805972.git.luto@kernel.org>
2016-03-12 18:08 ` [PATCH v4 1/5] x86/paravirt: Add _safe to the read_msr and write_msr PV hooks Andy Lutomirski
2016-03-12 18:08 ` [PATCH v4 2/5] x86/msr: Carry on after a non-"safe" MSR access fails without !panic_on_oops Andy Lutomirski
2016-03-12 18:08 ` [PATCH v4 3/5] x86/paravirt: Add paravirt_{read, write}_msr Andy Lutomirski
2016-03-12 18:08 ` [PATCH v4 4/5] x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y Andy Lutomirski
2016-03-12 18:08 ` [PATCH v4 5/5] x86/msr: Set the return value to zero when native_rdmsr_safe fails Andy Lutomirski
     [not found] ` <7e72cd6ce08b946872a462fad13eca1810b8671d.1457805972.git.luto@kernel.org>
2016-03-14 11:57   ` [PATCH v4 1/5] x86/paravirt: Add _safe to the read_msr and write_msr PV hooks Borislav Petkov
     [not found]   ` <20160314115729.GC15800@pd.tnic>
2016-03-14 17:07     ` Andy Lutomirski
     [not found] ` <a3b871a4eb533340d04255409dfecc94f88c647d.1457805972.git.luto@kernel.org>
2016-03-14 12:02   ` [PATCH v4 2/5] x86/msr: Carry on after a non-"safe" MSR access fails without !panic_on_oops Borislav Petkov
     [not found]   ` <20160314120202.GD15800@pd.tnic>
2016-03-14 17:05     ` Andy Lutomirski
     [not found]     ` <CALCETrW6E0Nz6gSmRKTvHbQDhnHVpuhzmgZB1nZ3m-DL-Bt=tQ@mail.gmail.com>
2016-03-14 17:11       ` Linus Torvalds
2016-03-14 17:17         ` Andy Lutomirski
     [not found]         ` <CALCETrXhXPj_b6rUMn=SR0QwE92rL=k5DCFraZwBj9FpUgadYw@mail.gmail.com>
2016-03-14 18:04           ` Linus Torvalds
     [not found]           ` <CA+55aFwr80aZ3-1H4VPB5=jeU_Yt=hYFfFvZC5-cNXzgXxGf3A@mail.gmail.com>
2016-03-14 18:10             ` Andy Lutomirski
2016-03-14 18:10             ` Linus Torvalds
     [not found]             ` <CALCETrV16vh5U0TRzdroSTBR_QHDX1C78t0DDW9qtKjOmV+2sQ@mail.gmail.com>
2016-03-14 18:15               ` Linus Torvalds
     [not found]               ` <CA+55aFz=PdvMWSsXExrpQC2UV6aLS+=+VOo+K4=njQoU5B9hgA@mail.gmail.com>
2016-03-14 18:24                 ` Andy Lutomirski
     [not found]                 ` <CALCETrXAAOcGP7DK+7aKn=2pu=SQ0n_PhG9bV4DcoYcv9epn4A@mail.gmail.com>
2016-03-14 18:40                   ` Linus Torvalds
     [not found]                   ` <CA+55aFy2dNgBJwjd+fRUYQf9OxqGkkcjUEarv+o3QSFTJ6+gJQ@mail.gmail.com>
2016-03-14 18:48                     ` Andy Lutomirski [this message]
     [not found]                     ` <CALCETrWxSBwwFTFsRoR_9AVBoC0iJ1pdWwOq_cnFf3NHUpG4QA@mail.gmail.com>
2016-03-15 10:22                       ` Ingo Molnar
     [not found]                       ` <20160315102230.GB23406@gmail.com>
2016-03-15 10:26                         ` Ingo Molnar
2016-03-14 20:18               ` Peter Zijlstra
2016-03-15 10:21             ` Ingo Molnar
2016-03-14 14:32 ` [PATCH v4 0/5] [PATCH v3 0/5] Improve non-"safe" MSR access failure handling Boris Ostrovsky

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='CALCETrWxSBwwFTFsRoR_9AVBoC0iJ1pdWwOq_cnFf3NHUpG4QA__4380.79764503545$1457981441$gmane$org@mail.gmail.com' \
    --to=luto@amacapital.net \
    --cc=Xen-devel@lists.xen.org \
    --cc=akpm@linux-foundation.org \
    --cc=arjan@linux.intel.com \
    --cc=bp@alien8.de \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=peterz@infradead.org \
    --cc=torvalds@linux-foundation.org \
    --cc=x86@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).