[PATCH 5.4 119/411] x86: Fix return value of __setup handlers

Greg Kroah-Hartman
2022-06-13T11:21:04Z

From: Randy Dunlap <rdunlap@infradead.org>

[ Upstream commit 12441ccdf5e2f5a01a46e344976cbbd3d46845c9 ]

__setup() handlers should return 1 to obsolete_checksetup() in
init/main.c to indicate that the boot option has been handled. A return
of 0 causes the boot option/value to be listed as an Unknown kernel
parameter and added to init's (limited) argument (no '=') or environment
(with '=') strings. So return 1 from these x86 __setup handlers.

Examples:

Unknown kernel command line parameters "apicpmtimer
BOOT_IMAGE=/boot/bzImage-517rc8 vdso=1 ring3mwait=disable", will be
passed to user space.

Run /sbin/init as init process
with arguments:
/sbin/init
apicpmtimer
with environment:
HOME=/
TERM=linux
BOOT_IMAGE=/boot/bzImage-517rc8
vdso=1
ring3mwait=disable

Fixes: 2aae950b21e4 ("x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu")
Fixes: 77b52b4c5c66 ("x86: add "debugpat" boot option")
Fixes: e16fd002afe2 ("x86/cpufeature: Enable RING3MWAIT for Knights Landing")
Fixes: b8ce33590687 ("x86_64: convert to clock events")
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Link: https://lore.kernel.org/r/20220314012725.26661-1-rdunlap@infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/entry/vdso/vma.c | 2 +-
arch/x86/kernel/apic/apic.c | 2 +-
arch/x86/kernel/cpu/intel.c | 2 +-
arch/x86/mm/pat.c | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index f5937742b290..3613cfb83c6d 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -323,7 +323,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
static __init int vdso_setup(char *s)
{
vdso64_enabled = simple_strtoul(s, NULL, 0);
- return 0;
+ return 1;
}
__setup("vdso=", vdso_setup);

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 4e4476b832be..68c734032523 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -168,7 +168,7 @@ static __init int setup_apicpmtimer(char *s)
{
apic_calibrate_pmtmr = 1;
notsc_setup(NULL);
- return 0;
+ return 1;
}
__setup("apicpmtimer", setup_apicpmtimer);
#endif
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 11d5c5950e2d..44688917d51f 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -97,7 +97,7 @@ static bool ring3mwait_disabled __read_mostly;
static int __init ring3mwait_disable(char *__unused)
{
ring3mwait_disabled = true;
- return 0;
+ return 1;
}
__setup("ring3mwait=disable", ring3mwait_disable);

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 35b2e35c2203..c7c4e2f8c6a5 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -75,7 +75,7 @@ int pat_debug_enable;
static int __init pat_debug_setup(char *str)
{
pat_debug_enable = 1;
- return 0;
+ return 1;
}
__setup("debugpat", pat_debug_setup);

--
2.35.1