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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.3 (3.54.3-1.fc41) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2025-09-15 at 19:51 +0000, Frank van der Linden wrote: >=20 > @@ -851,7 +862,10 @@ int __init > cma_declare_contiguous_multi(phys_addr_t total_size, > =C2=A0 list_for_each_safe(mp, next, &ranges) { > =C2=A0 mlp =3D list_entry(mp, struct cma_init_memrange, > list); > =C2=A0 list_del(mp); > - list_insert_sorted(&final_ranges, mlp, basecmp); > + if (flags & CMA_BALANCE) > + list_insert_sorted(&final_ranges, mlp, > revbasecmp); > + else > + list_insert_sorted(&final_ranges, mlp, > basecmp); > =C2=A0 sizesum +=3D mlp->size; > =C2=A0 if (sizesum >=3D total_size) > =C2=A0 break; Wait, what is this supposed to do when presented with a mix of CMA_BALANCE and !CMA_BALANCE ranges? I can't convince myself this would always keep the CMA_BALANCE range near the top of the list, and the others near the bottom. Also, does the regular compaction code pay any attention to the order of this list? I have the feeling I am overlooking something big in how this patch is supposed to work, but I am not sure what that would be... > @@ -866,7 +880,12 @@ int __init > cma_declare_contiguous_multi(phys_addr_t total_size, > =C2=A0 list_for_each(mp, &final_ranges) { > =C2=A0 mlp =3D list_entry(mp, struct cma_init_memrange, > list); > =C2=A0 size =3D min(sizeleft, mlp->size); > - if (memblock_reserve(mlp->base, size)) { > + if (flags & CMA_BALANCE) > + start =3D (mlp->base + mlp->size - size); > + else > + start =3D mlp->base; > + > + if (memblock_reserve(start, size)) { > =C2=A0 /* > =C2=A0 * Unexpected error. Could go on to > =C2=A0 * the next one, but just abort to >=20 --=20 All Rights Reversed.