timekeeping: Adjust the leap state for the correct auxiliary timekeeper

When __do_ajdtimex() was introduced to handle adjtimex for any
timekeeper, this reference to tk_core was not updated. When called on an
auxiliary timekeeper, the core timekeeper would be updated incorrectly.

This gets caught by the lock debugging diagnostics because the
timekeepers sequence lock gets written to without holding its
associated spinlock:

WARNING: include/linux/seqlock.h:226 at __do_adjtimex+0x394/0x3b0, CPU#2: test/125
aux_clock_adj (kernel/time/timekeeping.c:2979)
__do_sys_clock_adjtime (kernel/time/posix-timers.c:1161 kernel/time/posix-timers.c:1173)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)

Update the correct auxiliary timekeeper.

Fixes: 775f71ebedd3 ("timekeeping: Make do_adjtimex() reusable")
Fixes: ecf3e7030491 ("timekeeping: Provide adjtimex() for auxiliary clocks")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260120-timekeeper-auxclock-leapstate-v1-1-5b358c6b3cfd@linutronix.de

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 3ec3daa4acab5d603b96d0aa48880e9cc8f90afb..91fa2003351c9dead5871962502156de17c85b25 100644 (file)
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -2735,7 +2735,7 @@ static int __do_adjtimex(struct tk_data *tkd, struct __kernel_timex *txc,
                timekeeping_update_from_shadow(tkd, TK_CLOCK_WAS_SET);
                result->clock_set = true;
        } else {
-               tk_update_leap_state_all(&tk_core);
+               tk_update_leap_state_all(tkd);
        }
 
        /* Update the multiplier immediately if frequency was set directly */