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Re: [PATCH 01/16] x86/shadow: fix and improve sh_page_has_multiple_shadows()
- To: Jan Beulich <jbeulich@xxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
- From: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
- Date: Thu, 23 Mar 2023 11:55:31 +0000
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- Cc: Wei Liu <wl@xxxxxxx>, Roger Pau Monné <roger.pau@xxxxxxxxxx>, George Dunlap <george.dunlap@xxxxxxxxxx>, Tim Deegan <tim@xxxxxxx>
- Delivery-date: Thu, 23 Mar 2023 11:56:01 +0000
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- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 22/03/2023 9:29 am, Jan Beulich wrote:
> While no caller currently invokes the function without first making sure
> there is at least one shadow [1], we'd better eliminate UB here:
> find_first_set_bit() requires input to be non-zero to return a well-
> defined result.
>
> Further, using find_first_set_bit() isn't very efficient in the first
> place for the intended purpose.
>
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
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