Re: [Y2038] [PATCH] [v3] x86: Convert x86_platform_ops to timespec64

On 2018-04-27 22:13, Arnd Bergmann wrote:

The x86 platform operations are fairly isolated, so we can change them from using timespec to timespec64. I checked that All the users and callers are safe, and there is only one critical function that is broken beyond 2106:

pvclock_read_wallclock() uses a 32-bit number of seconds since the epoch to communicate the boot time between host and guest in a virtual environment. This will work until 2106, but we should ideally find a replacement anyway. I've added a comment about it there.

Reviewed-by: Boris Ostrovsky boris.ostrovsky@oracle.com Signed-off-by: Arnd Bergmann arnd@arndb.de

---

v2 changes:

• move comment block (Boris)
• remove unnecessary type cast (Boris)
• fix format string (0day bot)
• fix include order (0day bot)

v3 changes:

• add jailhouse specific change
• avoid include file header by relying on another patch ("timekeeping: Remove timespec64 hack")

Not sure how we want to merge this (assuming the last modification worked, this has seen little testing). The "timekeeping: Remove timespec64 hack" patch should go through the timekeeping branch in tip, while this one is for x86. I assume the linux-tip maintainers can come up with a plan.

---

arch/x86/include/asm/intel_mid_vrtc.h | 4 ++-- arch/x86/include/asm/mc146818rtc.h | 4 ++-- arch/x86/include/asm/pvclock.h | 2 +- arch/x86/include/asm/x86_init.h | 6 +++--- arch/x86/kernel/jailhouse.c | 2 +- arch/x86/kernel/kvmclock.c | 4 ++-- arch/x86/kernel/pvclock.c | 15 +++++++++++---- arch/x86/kernel/rtc.c | 10 +++++----- arch/x86/platform/intel-mid/intel_mid_vrtc.c | 12 ++++++------ arch/x86/xen/time.c | 10 +++++----- 10 files changed, 38 insertions(+), 31 deletions(-)

diff --git a/arch/x86/include/asm/intel_mid_vrtc.h b/arch/x86/include/asm/intel_mid_vrtc.h index 35555016b1be..0b44b1abe4d9 100644 --- a/arch/x86/include/asm/intel_mid_vrtc.h +++ b/arch/x86/include/asm/intel_mid_vrtc.h @@ -4,7 +4,7 @@ extern unsigned char vrtc_cmos_read(unsigned char reg); extern void vrtc_cmos_write(unsigned char val, unsigned char reg); -extern void vrtc_get_time(struct timespec *now); -extern int vrtc_set_mmss(const struct timespec *now); +extern void vrtc_get_time(struct timespec64 *now); +extern int vrtc_set_mmss(const struct timespec64 *now); #endif diff --git a/arch/x86/include/asm/mc146818rtc.h b/arch/x86/include/asm/mc146818rtc.h index 1775a32f7ea6..97198001e567 100644 --- a/arch/x86/include/asm/mc146818rtc.h +++ b/arch/x86/include/asm/mc146818rtc.h @@ -95,8 +95,8 @@ static inline unsigned char current_lock_cmos_reg(void) unsigned char rtc_cmos_read(unsigned char addr); void rtc_cmos_write(unsigned char val, unsigned char addr); -extern int mach_set_rtc_mmss(const struct timespec *now); -extern void mach_get_cmos_time(struct timespec *now); +extern int mach_set_rtc_mmss(const struct timespec64 *now); +extern void mach_get_cmos_time(struct timespec64 *now); #define RTC_IRQ 8 diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h index a7471dcd2205..b6033680d458 100644 --- a/arch/x86/include/asm/pvclock.h +++ b/arch/x86/include/asm/pvclock.h @@ -12,7 +12,7 @@ void pvclock_set_flags(u8 flags); unsigned long pvclock_tsc_khz(struct pvclock_vcpu_time_info *src); void pvclock_read_wallclock(struct pvclock_wall_clock *wall, struct pvclock_vcpu_time_info *vcpu,

• 	    struct timespec *ts);
  

• 	    struct timespec64 *ts);
  

void pvclock_resume(void); void pvclock_touch_watchdogs(void); diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index ce8b4da07e35..2d27236c16a3 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -170,7 +170,7 @@ struct x86_cpuinit_ops { void (*fixup_cpu_id)(struct cpuinfo_x86 *c, int node); }; -struct timespec; +struct timespec64; /**

• struct x86_legacy_devices - legacy x86 devices

@@ -264,8 +264,8 @@ struct x86_hyper_runtime { struct x86_platform_ops { unsigned long (*calibrate_cpu)(void); unsigned long (*calibrate_tsc)(void);

• void (*get_wallclock)(struct timespec *ts);
• int (*set_wallclock)(const struct timespec *ts);

• void (*get_wallclock)(struct timespec64 *ts);
• int (*set_wallclock)(const struct timespec64 *ts); void (*iommu_shutdown)(void); bool (*is_untracked_pat_range)(u64 start, u64 end); void (*nmi_init)(void);

diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c index fa183a131edc..a0b05bf185ac 100644 --- a/arch/x86/kernel/jailhouse.c +++ b/arch/x86/kernel/jailhouse.c @@ -37,7 +37,7 @@ static uint32_t __init jailhouse_detect(void) return jailhouse_cpuid_base(); } -static void jailhouse_get_wallclock(struct timespec *now) +static void jailhouse_get_wallclock(struct timespec64 *now) { memset(now, 0, sizeof(*now)); } diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 8b26c9e01cc4..bf8d1eb7fca3 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -53,7 +53,7 @@ static struct pvclock_wall_clock *wall_clock;

• have elapsed since the hypervisor wrote the data. So we try to account for
• that with system time

*/ -static void kvm_get_wallclock(struct timespec *now) +static void kvm_get_wallclock(struct timespec64 *now) { struct pvclock_vcpu_time_info *vcpu_time; int low, high; @@ -72,7 +72,7 @@ static void kvm_get_wallclock(struct timespec *now) put_cpu(); } -static int kvm_set_wallclock(const struct timespec *now) +static int kvm_set_wallclock(const struct timespec64 *now) { return -ENODEV; } diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c index 761f6af6efa5..637982efecd8 100644 --- a/arch/x86/kernel/pvclock.c +++ b/arch/x86/kernel/pvclock.c @@ -123,28 +123,35 @@ u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src) void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock, struct pvclock_vcpu_time_info *vcpu_time,

• 	    struct timespec *ts)
  

• 	    struct timespec64 *ts)
  

{ u32 version; u64 delta;

• struct timespec now;

• struct timespec64 now;

/* get wallclock at system boot */ do { version = wall_clock->version; rmb(); /* fetch version before time */

• /*
  

•  * Note: wall_clock->sec is a u32 value, so it can
  

•  * only store dates between 1970 and 2106. To allow
  

•  * times beyond that, we need to create a new hypercall
  

•  * interface with an extended pvclock_wall_clock structure
  

•  * like ARM has.
  

•  */
  

  now.tv_sec = wall_clock->sec; now.tv_nsec = wall_clock->nsec; rmb(); /* fetch time before checking version */ } while ((wall_clock->version & 1) || (version != wall_clock->version));

delta = pvclock_clocksource_read(vcpu_time); /* time since system boot */

• delta += now.tv_sec * (u64)NSEC_PER_SEC + now.tv_nsec;

• delta += now.tv_sec * NSEC_PER_SEC + now.tv_nsec;

now.tv_nsec = do_div(delta, NSEC_PER_SEC); now.tv_sec = delta;

• set_normalized_timespec(ts, now.tv_sec, now.tv_nsec);

• set_normalized_timespec64(ts, now.tv_sec, now.tv_nsec);

} void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti) diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c index f7b82ed7b5b5..586f718b8e95 100644 --- a/arch/x86/kernel/rtc.c +++ b/arch/x86/kernel/rtc.c @@ -39,7 +39,7 @@ EXPORT_SYMBOL(rtc_lock);

• jump to the next second precisely 500 ms later. Check the Motorola
• MC146818A or Dallas DS12887 data sheet for details.

*/ -int mach_set_rtc_mmss(const struct timespec *now) +int mach_set_rtc_mmss(const struct timespec64 *now) { unsigned long long nowtime = now->tv_sec; struct rtc_time tm; @@ -60,7 +60,7 @@ int mach_set_rtc_mmss(const struct timespec *now) return retval; } -void mach_get_cmos_time(struct timespec *now) +void mach_get_cmos_time(struct timespec64 *now) { unsigned int status, year, mon, day, hour, min, sec, century = 0; unsigned long flags; @@ -118,7 +118,7 @@ void mach_get_cmos_time(struct timespec *now) } else year += CMOS_YEARS_OFFS;

• now->tv_sec = mktime(year, mon, day, hour, min, sec);

• now->tv_sec = mktime64(year, mon, day, hour, min, sec); now->tv_nsec = 0;

} @@ -145,13 +145,13 @@ void rtc_cmos_write(unsigned char val, unsigned char addr) } EXPORT_SYMBOL(rtc_cmos_write); -int update_persistent_clock(struct timespec now) +int update_persistent_clock64(struct timespec64 now) { return x86_platform.set_wallclock(&now); } /* not static: needed by APM */ -void read_persistent_clock(struct timespec *ts) +void read_persistent_clock64(struct timespec64 *ts) { x86_platform.get_wallclock(ts); } diff --git a/arch/x86/platform/intel-mid/intel_mid_vrtc.c b/arch/x86/platform/intel-mid/intel_mid_vrtc.c index 58024862a7eb..a52914aa3b6c 100644 --- a/arch/x86/platform/intel-mid/intel_mid_vrtc.c +++ b/arch/x86/platform/intel-mid/intel_mid_vrtc.c @@ -57,7 +57,7 @@ void vrtc_cmos_write(unsigned char val, unsigned char reg) } EXPORT_SYMBOL_GPL(vrtc_cmos_write); -void vrtc_get_time(struct timespec *now) +void vrtc_get_time(struct timespec64 *now) { u8 sec, min, hour, mday, mon; unsigned long flags; @@ -83,18 +83,18 @@ void vrtc_get_time(struct timespec *now) pr_info("vRTC: sec: %d min: %d hour: %d day: %d " "mon: %d year: %d\n", sec, min, hour, mday, mon, year);

• now->tv_sec = mktime(year, mon, mday, hour, min, sec);

• now->tv_sec = mktime64(year, mon, mday, hour, min, sec); now->tv_nsec = 0;

} -int vrtc_set_mmss(const struct timespec *now) +int vrtc_set_mmss(const struct timespec64 *now) { unsigned long flags; struct rtc_time tm; int year; int retval = 0;

• rtc_time_to_tm(now->tv_sec, &tm);

• rtc_time64_to_tm(now->tv_sec, &tm); if (!rtc_valid_tm(&tm) && tm.tm_year >= 72) { /*
  • tm.year is the number of years since 1900, and the

@@ -110,8 +110,8 @@ int vrtc_set_mmss(const struct timespec *now) vrtc_cmos_write(tm.tm_sec, RTC_SECONDS); spin_unlock_irqrestore(&rtc_lock, flags); } else {

• pr_err("%s: Invalid vRTC value: write of %lx to vRTC failed\n",
  

• 	__func__, now->tv_sec);
  

• pr_err("%s: Invalid vRTC value: write of %llx to vRTC failed\n",
  

• 	__func__, (s64)now->tv_sec);
  

  retval = -EINVAL; } return retval;

diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 29163c43ebbd..e0f1bcf01d63 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -57,7 +57,7 @@ static u64 xen_clocksource_get_cycles(struct clocksource *cs) return xen_clocksource_read(); } -static void xen_read_wallclock(struct timespec *ts) +static void xen_read_wallclock(struct timespec64 *ts) { struct shared_info *s = HYPERVISOR_shared_info; struct pvclock_wall_clock *wall_clock = &(s->wc); @@ -68,12 +68,12 @@ static void xen_read_wallclock(struct timespec *ts) put_cpu_var(xen_vcpu); } -static void xen_get_wallclock(struct timespec *now) +static void xen_get_wallclock(struct timespec64 *now) { xen_read_wallclock(now); } -static int xen_set_wallclock(const struct timespec *now) +static int xen_set_wallclock(const struct timespec64 *now) { return -ENODEV; } @@ -461,7 +461,7 @@ static void __init xen_time_init(void) { struct pvclock_vcpu_time_info *pvti; int cpu = smp_processor_id();

• struct timespec tp;

• struct timespec64 tp;

/* As Dom0 is never moved, no penalty on using TSC there */ if (xen_initial_domain()) @@ -479,7 +479,7 @@ static void __init xen_time_init(void) /* Set initial system time with full resolution */ xen_read_wallclock(&tp);

• do_settimeofday(&tp);

• do_settimeofday64(&tp);

setup_force_cpu_cap(X86_FEATURE_TSC);

For the few Jailhouse bits.

Acked-by: Jan Kiszka jan.kiszka@siemens.com