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Date:   Wed, 29 Jun 2022 13:17:52 -0400
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Subject: Re: [PATCH v2 0/3] x86: fix brk area initialization
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To:     Juergen Gross <jgross@suse.com>, xen-devel@lists.xenproject.org,
        x86@kernel.org, linux-kernel@vger.kernel.org
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, regressions@lists.linux.dev
References: <20220623094608.7294-1-jgross@suse.com>
 <2592493b-4339-3e54-8acf-585dcf90be96@suse.com>
From:   Boris Ostrovsky <boris.ostrovsky@oracle.com>
In-Reply-To: <2592493b-4339-3e54-8acf-585dcf90be96@suse.com>
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On 6/29/22 10:10 AM, Juergen Gross wrote:
> On 23.06.22 11:46, Juergen Gross wrote:
>> The brk area needs to be zeroed initially, like the .bss section.
>> At the same time its memory should be covered by the ELF program
>> headers.
>>
>> Juergen Gross (3):
>>    x86/xen: use clear_bss() for Xen PV guests
>>    x86: fix setup of brk area
>>    x86: fix .brk attribute in linker script
>>
>>   arch/x86/include/asm/setup.h  |  3 +++
>>   arch/x86/kernel/head64.c      |  4 +++-
>>   arch/x86/kernel/vmlinux.lds.S |  2 +-
>>   arch/x86/xen/enlighten_pv.c   |  8 ++++++--
>>   arch/x86/xen/xen-head.S       | 10 +---------
>>   5 files changed, 14 insertions(+), 13 deletions(-)
>>
>
> Could I please have some feedback? This series is fixing a major
> regression regarding running as Xen PV guest (depending on kernel
> configuration system will crash very early).
>
> #regzbot ^introduced e32683c6f7d2
>


I don't think you need this for Xen bits as Jan had already reviewed it but in case you do


Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>