From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:41488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387859AbeKLITi (ORCPT ); Mon, 12 Nov 2018 03:19:38 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Fengguang Wu , Bart Van Assche , "Rafael J. Wysocki" Subject: [PATCH 4.18 020/350] ACPI / OSL: Use jiffies as the time bassis for acpi_os_get_timer() Date: Sun, 11 Nov 2018 14:18:04 -0800 Message-Id: <20181111221708.018543494@linuxfoundation.org> In-Reply-To: <20181111221707.043394111@linuxfoundation.org> References: <20181111221707.043394111@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche commit 83b2348e2755db48fa8f40fdb791f366fabc0ba0 upstream. Since acpi_os_get_timer() may be called after the timer subsystem has been suspended, use the jiffies counter instead of ktime_get(). This patch avoids that the following warning is reported during hibernation: WARNING: CPU: 0 PID: 612 at kernel/time/timekeeping.c:751 ktime_get+0x116/0x120 RIP: 0010:ktime_get+0x116/0x120 Call Trace: acpi_os_get_timer+0xe/0x30 acpi_ds_exec_begin_control_op+0x175/0x1de acpi_ds_exec_begin_op+0x2c7/0x39a acpi_ps_create_op+0x573/0x5e4 acpi_ps_parse_loop+0x349/0x1220 acpi_ps_parse_aml+0x25b/0x6da acpi_ps_execute_method+0x327/0x41b acpi_ns_evaluate+0x4e9/0x6f5 acpi_ut_evaluate_object+0xd9/0x2f2 acpi_rs_get_method_data+0x8f/0x114 acpi_walk_resources+0x122/0x1b6 acpi_pci_link_get_current.isra.2+0x157/0x280 acpi_pci_link_set+0x32f/0x4a0 irqrouter_resume+0x58/0x80 syscore_resume+0x84/0x380 hibernation_snapshot+0x20c/0x4f0 hibernate+0x22d/0x3a6 state_store+0x99/0xa0 kobj_attr_store+0x37/0x50 sysfs_kf_write+0x87/0xa0 kernfs_fop_write+0x1a5/0x240 __vfs_write+0xd2/0x410 vfs_write+0x101/0x250 ksys_write+0xab/0x120 __x64_sys_write+0x43/0x50 do_syscall_64+0x71/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 164a08cee135 (ACPICA: Dispatcher: Introduce timeout mechanism for infinite loop detection) Reported-by: Fengguang Wu References: https://lists.01.org/pipermail/lkp/2018-April/008406.html Signed-off-by: Bart Van Assche Cc: 4.16+ # 4.16+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/osl.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -617,15 +617,18 @@ void acpi_os_stall(u32 us) } /* - * Support ACPI 3.0 AML Timer operand - * Returns 64-bit free-running, monotonically increasing timer - * with 100ns granularity + * Support ACPI 3.0 AML Timer operand. Returns a 64-bit free-running, + * monotonically increasing timer with 100ns granularity. Do not use + * ktime_get() to implement this function because this function may get + * called after timekeeping has been suspended. Note: calling this function + * after timekeeping has been suspended may lead to unexpected results + * because when timekeeping is suspended the jiffies counter is not + * incremented. See also timekeeping_suspend(). */ u64 acpi_os_get_timer(void) { - u64 time_ns = ktime_to_ns(ktime_get()); - do_div(time_ns, 100); - return time_ns; + return (get_jiffies_64() - INITIAL_JIFFIES) * + (ACPI_100NSEC_PER_SEC / HZ); } acpi_status acpi_os_read_port(acpi_io_address port, u32 * value, u32 width)