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charset="us-ascii" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-OriginatorOrg: outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SN6PR02MB4157.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-RMS-PersistedConsumerOrg: 00000000-0000-0000-0000-000000000000 X-MS-Exchange-CrossTenant-Network-Message-Id: 2a6c3201-5364-433c-545e-08de225c69dd X-MS-Exchange-CrossTenant-originalarrivaltime: 13 Nov 2025 02:29:04.1056 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 84df9e7f-e9f6-40af-b435-aaaaaaaaaaaa X-MS-Exchange-CrossTenant-rms-persistedconsumerorg: 00000000-0000-0000-0000-000000000000 X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN6PR02MB10774 From: Josh Poimboeuf Sent: Wednesday, November 12, 20= 25 3:33 PM >=20 > With CONFIG_KLP_BUILD enabled, checksums are only needed during a > klp-build run. There's no need to enable them for normal kernel builds. >=20 > This also has the benefit of softening the xxhash dependency. >=20 > Signed-off-by: Josh Poimboeuf > --- > arch/x86/boot/startup/Makefile | 2 +- > scripts/Makefile.lib | 1 - > scripts/livepatch/klp-build | 4 ++++ > 3 files changed, 5 insertions(+), 2 deletions(-) >=20 > diff --git a/arch/x86/boot/startup/Makefile b/arch/x86/boot/startup/Makef= ile > index e8fdf020b422..5e499cfb29b5 100644 > --- a/arch/x86/boot/startup/Makefile > +++ b/arch/x86/boot/startup/Makefile > @@ -36,7 +36,7 @@ $(patsubst %.o,$(obj)/%.o,$(lib-y)): > OBJECT_FILES_NON_STANDARD :=3D y > # relocations, even if other objtool actions are being deferred. > # > $(pi-objs): objtool-enabled =3D 1 > -$(pi-objs): objtool-args =3D $(if $(delay-objtool),,$(objtool-args-y)) -= -noabs > +$(pi-objs): objtool-args =3D $(if $(delay-objtool),--dry-run,$(objtool-a= rgs-y)) --noabs >=20 > # > # Confine the startup code by prefixing all symbols with __pi_ (for posi= tion > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib > index f4b33919ec37..28a1c08e3b22 100644 > --- a/scripts/Makefile.lib > +++ b/scripts/Makefile.lib > @@ -173,7 +173,6 @@ ifdef CONFIG_OBJTOOL >=20 > objtool :=3D $(objtree)/tools/objtool/objtool >=20 > -objtool-args-$(CONFIG_KLP_BUILD) +=3D --checksum > objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK) +=3D --hacks=3Djump_label > objtool-args-$(CONFIG_HAVE_NOINSTR_HACK) +=3D --hacks=3Dnoinstr > objtool-args-$(CONFIG_MITIGATION_CALL_DEPTH_TRACKING) +=3D --hacks=3Dsky= lake > diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build > index 881e052e7fae..882272120c9e 100755 > --- a/scripts/livepatch/klp-build > +++ b/scripts/livepatch/klp-build > @@ -489,8 +489,11 @@ clean_kernel() { >=20 > build_kernel() { > local log=3D"$TMP_DIR/build.log" > + local objtool_args=3D() > local cmd=3D() >=20 > + objtool_args=3D("--checksum") > + > cmd=3D("make") >=20 > # When a patch to a kernel module references a newly created unexported > @@ -513,6 +516,7 @@ build_kernel() { > cmd+=3D("$VERBOSE") > cmd+=3D("-j$JOBS") > cmd+=3D("KCFLAGS=3D-ffunction-sections -fdata-sections") > + cmd+=3D("OBJTOOL_ARGS=3D${objtool_args[*]}") > cmd+=3D("vmlinux") > cmd+=3D("modules") >=20 > -- > 2.51.1 Did a normal linux-next kernel build on an Ubuntu 20.04 system, which by de= fault does not have xxhash installed. Previous error about needing to install lib= xxhash-dev is no longer generated. Have not tested a klp-build. Tested-by: Michael Kelley