Re: + ipc-sem-use-flexible-array-in-struct-sem_undo.patch added to mm-nonmm-unstable branch

From: Manfred Spraul
Date: Wed Jul 19 2023 - 13:18:06 EST


Hi Christophe,

On 7/10/23 22:35, Andrew Morton wrote:
The patch titled
Subject: ipc/sem: use flexible array in 'struct sem_undo'
has been added to the -mm mm-nonmm-unstable branch. Its filename is
ipc-sem-use-flexible-array-in-struct-sem_undo.patch

This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/ipc-sem-use-flexible-array-in-struct-sem_undo.patch

This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Subject: ipc/sem: use flexible array in 'struct sem_undo'
Date: Sun, 9 Jul 2023 18:12:55 +0200

Turn 'semadj' in 'struct sem_undo' into a flexible array.

The advantages are:
- save the size of a pointer when the new undo structure is allocated
- avoid some always ugly pointer arithmetic to get the address of semadj
- avoid an indirection when the array is accessed

While at it, use struct_size() to compute the size of the new undo
structure.

Link: https://lkml.kernel.org/r/1ba993d443ad7e16ac2b1902adab1f05ebdfa454.1688918791.git.christophe.jaillet@xxxxxxxxxx
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Cc: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>

Reviewed-by: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>


--

    Manfred