Re: [PATCH 1/2] x86: Check return values from early_memremap calls

[Jan Kiszka <jan.kiszka@siemens.com>]

On 08.10.22 17:12, Borislav Petkov wrote:
> Adding Xen and Jailhouse people and MLs to Cc.
> 
> Folks, thread starts here:
> 
> https://lore.kernel.org/r/1650035401-22855-1-git-send-email-ross.philipson@oracle.com
> 
> On Fri, Apr 15, 2022 at 11:10:00AM -0400, Ross Philipson wrote:
>> There are a number of places where early_memremap is called
>> but the return pointer is not checked for NULL. The call
>> can result in a NULL being returned so the checks must
>> be added.
>>
>> Signed-off-by: Ross Philipson <ross.philipson@oracle.com>
>> ---
>>  arch/x86/kernel/devicetree.c | 10 ++++++++++
>>  arch/x86/kernel/e820.c       |  5 +++++
>>  arch/x86/kernel/jailhouse.c  |  6 ++++++
>>  arch/x86/kernel/mpparse.c    | 23 +++++++++++++++++++++++
>>  arch/x86/kernel/setup.c      |  5 +++++
>>  arch/x86/xen/enlighten_hvm.c |  2 ++
>>  arch/x86/xen/mmu_pv.c        |  8 ++++++++
>>  arch/x86/xen/setup.c         |  2 ++
>>  8 files changed, 61 insertions(+)
> 
> Ok, a couple of notes:
> 
> 1. the pr_*("<prefix>:" ... )
> 
> thing is done using pr_fmt() - grep the tree for examples.
> 
> 2. I think you should not panic() the machine but issue a the
> warning/error and let the machine die a painful death anyway. But Xen
> folks will know better what would be the optimal thing to do.
> 
> Thx.
> 

For the Jailhouse bits:

Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>

(IOW, panic'ing is fine for us here)

Thanks,
Jan

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