Zhang Jianhua 38fa3206bf efi: Change down_interruptible() in virt_efi_reset_system() to down_trylock() ... While reboot the system by sysrq, the following bug will be occur. BUG: sleeping function called from invalid context at kernel/locking/semaphore.c:90 in_atomic(): 0, irqs_disabled(): 128, non_block: 0, pid: 10052, name: rc.shutdown CPU: 3 PID: 10052 Comm: rc.shutdown Tainted: G W O 5.10.0 #1 Call trace: dump_backtrace+0x0/0x1c8 show_stack+0x18/0x28 dump_stack+0xd0/0x110 ___might_sleep+0x14c/0x160 __might_sleep+0x74/0x88 down_interruptible+0x40/0x118 virt_efi_reset_system+0x3c/0xd0 efi_reboot+0xd4/0x11c machine_restart+0x60/0x9c emergency_restart+0x1c/0x2c sysrq_handle_reboot+0x1c/0x2c __handle_sysrq+0xd0/0x194 write_sysrq_trigger+0xbc/0xe4 proc_reg_write+0xd4/0xf0 vfs_write+0xa8/0x148 ksys_write+0x6c/0xd8 __arm64_sys_write+0x18/0x28 el0_svc_common.constprop.3+0xe4/0x16c do_el0_svc+0x1c/0x2c el0_svc+0x20/0x30 el0_sync_handler+0x80/0x17c el0_sync+0x158/0x180 The reason for this problem is that irq has been disabled in machine_restart() and then it calls down_interruptible() in virt_efi_reset_system(), which would occur sleep in irq context, it is dangerous! Commit 99409b935c9a("locking/semaphore: Add might_sleep() to down_*() family") add might_sleep() in down_interruptible(), so the bug info is here. down_trylock() can solve this problem, cause there is no might_sleep. -------- Cc: <stable@vger.kernel.org> Signed-off-by: Zhang Jianhua <chris.zjh@huawei.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>		2021-10-05 13:07:01 +02:00
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libstub	efi/libstub: Simplify "Exiting bootservices" message	2021-10-05 13:05:58 +02:00
test	efi/efi_test: read RuntimeServicesSupported	2020-12-09 08:37:27 +01:00
apple-properties.c	efi/apple-properties: Handle device properties with software node API	2021-05-22 14:06:59 +02:00
arm-runtime.c	mm: reorder includes after introduction of linux/pgtable.h	2020-06-09 09:39:13 -07:00
capsule-loader.c	efi/capsule-loader: Drop superfluous assignment	2020-02-23 21:58:31 +01:00
capsule.c	efi: capsule: clean scatter-gather entries from the D-cache	2020-12-09 08:37:27 +01:00
cper-arm.c
cper-x86.c	x86/mce, cper: Pass x86 CPER through the MCA handling chain	2020-11-21 12:05:41 +01:00
cper.c	efi/cper: use stack buffer for error record decoding	2021-10-05 13:05:59 +02:00
dev-path-parser.c	ACPI: utils: Fix reference counting in for_each_acpi_dev_match()	2021-07-19 16:22:01 +02:00
earlycon.c	efi/earlycon: Fix early printk for wider fonts	2020-05-12 12:29:45 +02:00
efi-bgrt.c	efi/bgrt: Accept BGRT tables with a version of 0	2020-02-22 23:37:37 +01:00
efi-init.c	drivers/firmware: consolidate EFI framebuffer setup for all arches	2021-07-21 12:04:56 +02:00
efi-pstore.c	efi: pstore: move workqueue handling out of efivars	2020-09-29 19:40:57 +02:00
efi.c	firmware/efi: Tell memblock about EFI iomem reservations	2021-07-16 18:05:49 +02:00
efibc.c	efi: efibc: check for efivars write capability	2020-09-15 18:22:47 +03:00
efivars.c	efi: efivars: limit availability to X86 builds	2020-09-29 19:40:57 +02:00
embedded-firmware.c	crypto: sha - split sha.h into sha1.h and sha2.h	2020-11-20 14:45:33 +11:00
esrt.c	efi/esrt: Fix reference count leak in esre_create_sysfs_entry.	2020-06-15 14:38:56 +02:00
fake_mem.c	efi: Fix handling of multiple efi_fake_mem= entries	2020-01-20 08:14:29 +01:00
fake_mem.h	x86/efi: Add efi_fake_mem support for EFI_MEMORY_SP	2019-11-07 15:44:23 +01:00
fdtparams.c	efi/fdt: fix panic when no valid fdt found	2021-05-22 14:03:42 +02:00
Kconfig	EFI updates collected by Ard Biesheuvel:	2020-12-24 12:40:07 -08:00
Makefile	drivers/firmware: move x86 Generic System Framebuffers support	2021-07-21 12:04:56 +02:00
memattr.c	efi: Allow EFI_MEMORY_XP and EFI_MEMORY_RO both to be cleared	2021-05-22 14:05:13 +02:00
memmap.c	efi: Fix handling of multiple efi_fake_mem= entries	2020-01-20 08:14:29 +01:00
mokvar-table.c	efi/mokvar: Reserve the table only if it is in boot services data	2021-07-20 09:28:09 +02:00
rci2-table.c	efi: Don't attempt to map RCI2 config table if it doesn't exist	2019-12-10 12:13:02 +01:00
reboot.c	efi: Use EFI ResetSystem only when available	2020-02-23 21:59:42 +01:00
riscv-runtime.c	RISC-V: Add EFI runtime services	2020-10-02 14:31:28 -07:00
runtime-map.c
runtime-wrappers.c	efi: Change down_interruptible() in virt_efi_reset_system() to down_trylock()	2021-10-05 13:07:01 +02:00
sysfb_efi.c	efi: sysfb_efi: fix build when EFI is not set	2021-07-27 11:52:51 +02:00
tpm.c	efi/tpm: Differentiate missing and invalid final event log table.	2021-07-16 18:04:55 +02:00
vars.c	efivars: respect EFI_UNSUPPORTED return from firmware	2021-03-17 09:40:24 +01:00
x86_fake_mem.c	efi/fake_mem: arrange for a resource entry per efi_fake_mem instance	2020-10-13 18:38:27 -07:00