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Re: [PATCH v2 2/7] x86: Remove return value from UPDATE_ENTRY
- To: Kevin Lampis <kevin.lampis@xxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxxx
- From: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
- Date: Fri, 11 Sep 2026 16:01:43 +0100
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- Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, jbeulich@xxxxxxxx, teddy.astie@xxxxxxxxxx
- Delivery-date: Fri, 11 Sep 2026 15:02:01 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 10/09/2026 9:31 pm, Kevin Lampis wrote:
> UPDATE_ENTRY/update_intpte always returns true since 1bc30c076a7f
> "x86/mm: {paging, sh}_{cmpxchg, write}_guest_entry() cannot fault"
>
> Signed-off-by: Kevin Lampis <kevin.lampis@xxxxxxxxxx>
> ---
> Changes in v2:
> - New patch
> ---
> xen/arch/x86/mm.c | 74 +++++++++------------------------
> xen/arch/x86/pv/grant_table.c | 53 +++++++++++------------
> xen/arch/x86/pv/mm.h | 6 +--
> xen/arch/x86/pv/ro-page-fault.c | 3 +-
> 4 files changed, 46 insertions(+), 90 deletions(-)
Interestingly, despite being a static line, the optimiser can't make
this simplification all on it's own.
Bloat-o-meter reports:
add/remove: 0/0 grow/shrink: 3/1 up/down: 6/-32 (-26)
Function old new delta
symbols_offsets 53584 53588 +4
symbols_names 135144 135145 +1
mod_l1_entry 1872 1873 +1
do_mmu_update 5604 5572 -32
I've checked several times now, and I can't see anything which
constitutes a logical change here.
Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
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