Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8778AC636D4 for ; Fri, 17 Feb 2023 08:24:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229829AbjBQIXt (ORCPT ); Fri, 17 Feb 2023 03:23:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229840AbjBQIXq (ORCPT ); Fri, 17 Feb 2023 03:23:46 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E323D5F276; Fri, 17 Feb 2023 00:23:43 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4090CC14; Fri, 17 Feb 2023 00:24:26 -0800 (PST) Received: from [10.57.50.168] (unknown [10.57.50.168]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E00273F703; Fri, 17 Feb 2023 00:23:41 -0800 (PST) Message-ID: <1db35c72-c925-f33e-1cf3-2068658893b9@arm.com> Date: Fri, 17 Feb 2023 09:23:37 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [PATCH v1] arm64: efi: Make efi_rt_lock a raw_spinlock To: Ard Biesheuvel Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , linux-efi@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20230215161047.94803-1-pierre.gondois@arm.com> <19209817-6451-76de-70a4-1f89808bc82a@arm.com> Content-Language: en-US From: Pierre Gondois In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Ard, On 2/16/23 18:23, Ard Biesheuvel wrote: > On Thu, 16 Feb 2023 at 17:43, Pierre Gondois wrote: >> >> Hello, >> Please ignore this patch for now. While running a kernel with this patch, >> the following was triggered once (among multiple reboots). IRQ flags might >> need to be saved, along with this present patch. >> > > Hello Pierre, > > This is probably related to the Altra firmware bug that we are trying > to narrow down and work around. > > So when the firmware crashes, it is not entirely unexpected that it > might do so with the IRQ flags left in a different state, so this we > should be able to ignore. (Perhaps we should silence that diagnostic > in this case) > > Could you share the output of dmidecode on this platform? I forgot to mention, this was tested on an Ampere eMAG. I saw that commit 550b33cfd445 ("arm64: efi: Force the use of SetVirtualAddressMap() on Altra machines") was solving a similar issue, but this should not impact this machine. I ll try to reproduce it and get more information. # dmidecode 3.2 Getting SMBIOS data from sysfs. SMBIOS 3.1.1 present. Table at 0x8FFCAC0000. Handle 0x0000, DMI type 0, 26 bytes BIOS Information Vendor: Ampere(TM) Version: 1.0 Release Date: 06/28/2019 Address: 0xF0000 Runtime Size: 64 kB ROM Size: 8192 kB Characteristics: PCI is supported BIOS is upgradeable Boot from CD is supported Selectable boot is supported ACPI is supported UEFI is supported BIOS Revision: 5.13 Firmware Revision: 1.0 Handle 0x0001, DMI type 1, 27 bytes System Information Manufacturer: MiTAC Product Name: RAPTOR EV-883832-X3-0001 Version: PR010 Serial Number: 2AC2-B91602C UUID: dfa0f1d6-835d-11e8-adb0-0cc47ad8d1fc Wake-up Type: Power Switch SKU Number: EV-883832-X3-OBX-1 Family: eMAG Handle 0x0002, DMI type 2, 15 bytes Base Board Information Manufacturer: MiTAC Product Name: RAPTOR Version: EV-883832-X3-ED0-1 Serial Number: 2AC2-B91602C Asset Tag: AMPX3A1-A000-0000000000022 Features: Board is a hosting board Location In Chassis: Part Component Chassis Handle: 0x0003 Type: Motherboard Contained Object Handles: 0 Handle 0x0003, DMI type 3, 22 bytes Chassis Information Manufacturer: MiTAC Type: Rack Mount Chassis Lock: Not Present Version: RAPTOR-00000000 Serial Number: A1A1-A000-0000000000022 Asset Tag: AMPX3A1-A000-0000000000022 Boot-up State: Safe Power Supply State: Safe Thermal State: Safe Security Status: None OEM Information: 0x00000000 Height: Unspecified Number Of Power Cords: 1 Contained Elements: 0 SKU Number: EV-883832-X3-OBX-1 Handle 0x0004, DMI type 4, 48 bytes Processor Information Socket Designation: CPU 1 Type: Central Processor Family: ARMv8 Manufacturer: Ampere(TM) ID: 00 00 00 00 02 00 3F 50 Version: eMAG Voltage: 0.9 V External Clock: 3000 MHz Max Speed: 3300 MHz Current Speed: 3000 MHz Status: Populated, Enabled Upgrade: None L1 Cache Handle: 0x0005 L2 Cache Handle: 0x0006 L3 Cache Handle: 0x0007 Serial Number: 00000000000000005011060302FB0988 Asset Tag: 00000000 Part Number: 00000000 Core Count: 32 Core Enabled: 32 Thread Count: 32 Characteristics: 64-bit capable Multi-Core Hardware Thread Execute Protection Enhanced Virtualization [...] > > Obviously, there is a related issue where some process keeps hitting > on the RTC. Mind testing the below to see if the system is usable > beyond the EFI problems, and perhaps have a stab at figuring out which > process keeps hitting on the RTC like that? > > diff --git a/drivers/rtc/rtc-efi.c b/drivers/rtc/rtc-efi.c > index 1e8bc6cc1e12d855..cc4edb85841e8f67 100644 > --- a/drivers/rtc/rtc-efi.c > +++ b/drivers/rtc/rtc-efi.c > @@ -164,7 +164,7 @@ static int efi_read_time(struct device *dev, > struct rtc_time *tm) > > if (status != EFI_SUCCESS) { > /* should never happen */ > - dev_err(dev, "can't read time\n"); > + dev_err_ratelimited(dev, "can't read time\n"); > return -EINVAL; > } > > > >> >> random: crng init done >> [Firmware Bug]: Unable to handle write to read-only memory in EFI runtime service >> ------------[ cut here ]------------ >> WARNING: CPU: 7 PID: 325 at drivers/firmware/efi/runtime-wrappers.c:113 efi_call_virt_check_flags+0x48/0xb0 >> Modules linked in: btrfs blake2b_generic libcrc32c xor xor_neon raid6_pq crct10dif_ce >> CPU: 7 PID: 325 Comm: kworker/u64:1 Tainted: G W I 6.2.0-rc8-rt1-[...] >> Hardware name: MiTAC RAPTOR EV-883832-X3-0001/RAPTOR, BIOS 1.0 06/28/2019 >> Workqueue: efi_rts_wq efi_call_rts >> pstate: 00000085 (nzcv daIf -PAN -UAO -TCO -DIT -SSBS BTYPE=--) >> pc : efi_call_virt_check_flags+0x48/0xb0 >> lr : efi_call_rts+0x240/0x4b0 >> sp : ffff80000def3cf0 >> x29: ffff80000def3cf0 x28: ffff000801d10b05 x27: ffff80000b16d000 >> x26: 0000000000000000 x25: ffff80000b17e4a0 x24: ffff80000c84bd48 >> x23: ffff80000c84bd00 x22: ffff80000c84bd0c x21: 0000000000000080 >> x20: ffff80000a41d0e0 x19: 0000000000000000 x18: ffff80000a22b3a8 >> x17: 0000000000000000 x16: ffff80000d2dc000 x15: 0000000000000000 >> x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 >> x11: 0000000000000000 x10: 0000000000000000 x9 : ffff80000927cd60 >> x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 >> x5 : ffff80000a7d1008 x4 : 0000008ffd1d0018 x3 : 0000000000000000 >> x2 : 0000000000000001 x1 : ffff80000a41d0e0 x0 : 0000000000000080 >> Call trace: >> efi_call_virt_check_flags+0x48/0xb0 >> efi_call_rts+0x240/0x4b0 >> process_one_work+0x2c8/0x7a0 >> worker_thread+0x54/0x410 >> kthread+0x130/0x140 >> ret_from_fork+0x10/0x20 >> irq event stamp: 540538 >> hardirqs last enabled at (540537): [] efi_virtmap_load+0x28c/0x328 >> hardirqs last disabled at (540538): [] el1_abort+0x28/0x100 >> softirqs last enabled at (534078): [] __local_bh_enable_ip+0xa8/0x2a8 >> softirqs last disabled at (534066): [] neigh_managed_work+0x8/0x100 >> ---[ end trace 0000000000000000 ]--- >> Disabling lock debugging due to kernel taint >> efi: [Firmware Bug]: IRQ flags corrupted (0x00000000=>0x00000080) by EFI set_variable >> ------------[ cut here ]------------ >> WARNING: CPU: 0 PID: 14 at drivers/firmware/efi/runtime-wrappers.c:341 virt_efi_set_variable+0x164/0x1c0 >> Modules linked in: btrfs blake2b_generic libcrc32c xor xor_neon raid6_pq crct10dif_ce >> CPU: 0 PID: 14 Comm: kworker/0:1 Tainted: G W I 6.2.0-rc8-rt1-custom-[...] >> Hardware name: MiTAC RAPTOR EV-883832-X3-0001/RAPTOR, BIOS 1.0 06/28/2019 >> Workqueue: events refresh_nv_rng_seed >> pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) >> pc : virt_efi_set_variable+0x164/0x1c0 >> lr : virt_efi_set_variable+0x150/0x1c0 >> sp : ffff80000c84bcc0 >> x29: ffff80000c84bcc0 x28: ffff008f35feb905 x27: ffff80000b16d000 >> x26: ffff80000b16ced0 x25: 0000000000000000 x24: ffff80000c344000 >> x23: ffff80000a41b2b0 x22: ffff80000c84bd38 x21: 8000000000000015 >> x20: ffff80000b63ecf8 x19: ffff80000c344480 x18: ffff80000a22b3a8 >> x17: 000000005a8ae2d0 x16: 0000000000000000 x15: ffff80000b16cfb8 >> x14: 0000000000000001 x13: 0000000000000030 x12: 0101010101010101 >> x11: 0000000571f160b9 x10: 0000000000002460 x9 : ffff8000095e2064 >> x8 : ffff80000a7d1008 x7 : 0000000000000004 x6 : ffff80000c84bb28 >> x5 : ffff80000c84c000 x4 : ffff80000c848000 x3 : ffff80000c84bc40 >> x2 : 0000000000000001 x1 : 0000000000000000 x0 : 8000000000000015 >> Call trace: >> virt_efi_set_variable+0x164/0x1c0 >> refresh_nv_rng_seed+0x84/0xb8 >> process_one_work+0x2c8/0x7a0 >> worker_thread+0x54/0x410 >> kthread+0x130/0x140 >> ret_from_fork+0x10/0x20 >> irq event stamp: 35886 >> hardirqs last enabled at (35885): [] _raw_spin_unlock_irq+0x40/0xb8 >> hardirqs last disabled at (35886): [] _raw_spin_lock_irq+0x94/0x98 >> softirqs last enabled at (10754): [] __local_bh_enable_ip+0xa8/0x2a8 >> softirqs last disabled at (10746): [] srcu_invoke_callbacks+0x100/0x1a8 >> ---[ end trace 0000000000000000 ]--- >> [...] >> In-situ OAM (IOAM) with IPv6 >> efi: EFI Runtime Services are disabled! >> efivars: get_next_variable: status=8000000000000007 >> [...] >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> rtc-efi rtc-efi.0: can't read time >> [...] >> >> >> On 2/15/23 17:10, Pierre Gondois wrote: >>> Running a rt-kernel base on 6.2.0-rc3-rt1 on an Ampere Altra outputs >>> the following: >>> BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 >>> in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9, name: kworker/u320:0 >>> preempt_count: 2, expected: 0 >>> RCU nest depth: 0, expected: 0 >>> 3 locks held by kworker/u320:0/9: >>> #0: ffff3fff8c27d128 ((wq_completion)efi_rts_wq){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41) >>> #1: ffff80000861bdd0 ((work_completion)(&efi_rts_work.work)){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41) >>> #2: ffffdf7e1ed3e460 (efi_rt_lock){+.+.}-{3:3}, at: efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101) >>> Preemption disabled at: >>> efi_virtmap_load (./arch/arm64/include/asm/mmu_context.h:248) >>> CPU: 0 PID: 9 Comm: kworker/u320:0 Tainted: G W 6.2.0-rc3-rt1 >>> Hardware name: WIWYNN Mt.Jade Server System B81.03001.0005/Mt.Jade Motherboard, BIOS 1.08.20220218 (SCP: 1.08.20220218) 2022/02/18 >>> Workqueue: efi_rts_wq efi_call_rts >>> Call trace: >>> dump_backtrace (arch/arm64/kernel/stacktrace.c:158) >>> show_stack (arch/arm64/kernel/stacktrace.c:165) >>> dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4)) >>> dump_stack (lib/dump_stack.c:114) >>> __might_resched (kernel/sched/core.c:10134) >>> rt_spin_lock (kernel/locking/rtmutex.c:1769 (discriminator 4)) >>> efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101) >>> [...] >>> >>> This seems to come from commit ff7a167961d1 ("arm64: efi: Execute >>> runtime services from a dedicated stack") which adds a spinlock. This >>> spinlock is taken through: >>> efi_call_rts() >>> \-efi_call_virt() >>> \-efi_call_virt_pointer() >>> \-arch_efi_call_virt_setup() >>> >>> Make 'efi_rt_lock' a raw_spinlock to avoid being preempted. >>> >>> Signed-off-by: Pierre Gondois >>> --- >>> arch/arm64/include/asm/efi.h | 6 +++--- >>> arch/arm64/kernel/efi.c | 2 +- >>> 2 files changed, 4 insertions(+), 4 deletions(-) >>> >>> diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h >>> index 31d13a6001df..37dc2e8c3500 100644 >>> --- a/arch/arm64/include/asm/efi.h >>> +++ b/arch/arm64/include/asm/efi.h >>> @@ -33,7 +33,7 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); >>> ({ \ >>> efi_virtmap_load(); \ >>> __efi_fpsimd_begin(); \ >>> - spin_lock(&efi_rt_lock); \ >>> + raw_spin_lock(&efi_rt_lock); \ >>> }) >>> >>> #undef arch_efi_call_virt >>> @@ -42,12 +42,12 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md); >>> >>> #define arch_efi_call_virt_teardown() \ >>> ({ \ >>> - spin_unlock(&efi_rt_lock); \ >>> + raw_spin_unlock(&efi_rt_lock); \ >>> __efi_fpsimd_end(); \ >>> efi_virtmap_unload(); \ >>> }) >>> >>> -extern spinlock_t efi_rt_lock; >>> +extern raw_spinlock_t efi_rt_lock; >>> efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...); >>> >>> #define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT) >>> diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c >>> index fab05de2e12d..216933cf47ee 100644 >>> --- a/arch/arm64/kernel/efi.c >>> +++ b/arch/arm64/kernel/efi.c >>> @@ -145,7 +145,7 @@ asmlinkage efi_status_t efi_handle_corrupted_x18(efi_status_t s, const char *f) >>> return s; >>> } >>> >>> -DEFINE_SPINLOCK(efi_rt_lock); >>> +DEFINE_RAW_SPINLOCK(efi_rt_lock); >>> >>> asmlinkage u64 *efi_rt_stack_top __ro_after_init; >>>