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Message-ID: <44b4b20a-550c-6337-3f7d-8283498f76f2@intel.com>
Date:   Thu, 22 Sep 2022 08:00:33 -0700
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Subject: Re: [PATCH v2] x86/mm: Refuse W^X violations
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To:     Peter Zijlstra <peterz@infradead.org>,
        Guenter Roeck <linux@roeck-us.net>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org, keescook@chromium.org,
        Sean Christopherson <seanjc@google.com>
References: <YwySW3ROc21hN7g9@hirez.programming.kicks-ass.net>
 <20220921200726.GA3094503@roeck-us.net>
 <4dd594ad-490a-68ee-9e32-fbd9f135bd54@intel.com>
 <1a6e7165-cdae-6c8c-f57d-159fdb68897b@roeck-us.net>
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 <YywS0keUorHwJJPt@hirez.programming.kicks-ass.net>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <YywS0keUorHwJJPt@hirez.programming.kicks-ass.net>
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On 9/22/22 00:46, Peter Zijlstra wrote:
> On Wed, Sep 21, 2022 at 08:09:13PM -0700, Guenter Roeck wrote:
> 
>> Oh well, that "helped" to hide one of the crashes. Here is another one.
>> This is with PAE enabled and booting through efi32.
> 
>> [    1.086592]  efi_runtime_update_mappings+0x36/0x42
>> [    1.086717]  efi_enter_virtual_mode+0x351/0x36e
>> [    1.086860]  start_kernel+0x57d/0x60f
>> [    1.086956]  ? set_intr_gate+0x42/0x55
>> [    1.087079]  i386_start_kernel+0x43/0x45
>> [    1.087272]  startup_32_smp+0x161/0x164
> 
> Does this help? Dave; perhaps we should just let i386 be i386 and let it
> bitrot :/

How about we just turn off enforcement for now so that the poor i386
folks can at least boot?  I have the feeling we're going to get bored
with even the warnings if they persist for too long, though.

Untested patch to make i386 violations harmless is attached.
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