Thadeu Lima de Souza Cascardo 545fc3524c x86/bugs: Do not enable IBPB at firmware entry when IBPB is not available ... commit 571c30b1a88465a1c85a6f7762609939b9085a15 upstream. Some cloud hypervisors do not provide IBPB on very recent CPU processors, including AMD processors affected by Retbleed. Using IBPB before firmware calls on such systems would cause a GPF at boot like the one below. Do not enable such calls when IBPB support is not present. EFI Variables Facility v0.08 2004-May-17 general protection fault, maybe for address 0x1: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 24 Comm: kworker/u2:1 Not tainted 5.19.0-rc8+ #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 Workqueue: efi_rts_wq efi_call_rts RIP: 0010:efi_call_rts Code: e8 37 33 58 ff 41 bf 48 00 00 00 49 89 c0 44 89 f9 48 83 c8 01 4c 89 c2 48 c1 ea 20 66 90 b9 49 00 00 00 b8 01 00 00 00 31 d2 <0f> 30 e8 7b 9f 5d ff e8 f6 f8 ff ff 4c 89 f1 4c 89 ea 4c 89 e6 48 RSP: 0018:ffffb373800d7e38 EFLAGS: 00010246 RAX: 0000000000000001 RBX: 0000000000000006 RCX: 0000000000000049 RDX: 0000000000000000 RSI: ffff94fbc19d8fe0 RDI: ffff94fbc1b2b300 RBP: ffffb373800d7e70 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000000b R11: 000000000000000b R12: ffffb3738001fd78 R13: ffff94fbc2fcfc00 R14: ffffb3738001fd80 R15: 0000000000000048 FS: 0000000000000000(0000) GS:ffff94fc3da00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff94fc30201000 CR3: 000000006f610000 CR4: 00000000000406f0 Call Trace: <TASK> ? __wake_up process_one_work worker_thread ? rescuer_thread kthread ? kthread_complete_and_exit ret_from_fork </TASK> Modules linked in: Fixes: 28a99e95f55c ("x86/amd: Use IBPB for firmware calls") Reported-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220728122602.2500509-1-cascardo@canonical.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-08-03 12:00:51 +02:00
..
alpha	tty: the rest, stop using tty_schedule_flip()	2022-07-29 17:19:28 +02:00
arc	ARC: entry: fix syscall_trace_exit argument	2022-04-27 13:53:55 +02:00
arm	ARM: 9216/1: Fix MAX_DMA_ADDRESS overflow	2022-08-03 12:00:50 +02:00
arm64	arm64: dts: qcom: msm8992-*: Fix vdd_lvs1_2-supply typo	2022-07-12 16:32:20 +02:00
c6x	arch-cleanup-2020-10-22	2020-10-23 10:06:38 -07:00
csky	csky: patch_text: Fixup last cpu should be master	2022-06-09 10:21:26 +02:00
h8300	h8300: fix PREEMPTION build, TI_PRE_COUNT undefined	2021-02-17 11:02:28 +01:00
hexagon	hexagon: clean up timer-regs.h	2021-11-26 10:39:19 +01:00
ia64	ia64: define get_cycles macro for arch-override	2022-05-30 09:33:40 +02:00
m68k	Revert "m68knommu: only set CONFIG_ISA_DMA_API for ColdFire sub-arch"	2022-07-29 17:19:09 +02:00
microblaze	uaccess: fix nios2 and microblaze get_user_8()	2022-04-08 14:40:08 +02:00
mips	MIPS: Remove repetitive increase irq_err_count	2022-06-29 08:59:48 +02:00
nds32	nds32: fix access_ok() checks in get/put_user	2022-03-28 09:57:10 +02:00
nios2	nios2: use fallback for random_get_entropy() instead of zero	2022-05-30 09:33:41 +02:00
openrisc	openrisc: start CPU timer early in boot	2022-06-09 10:20:55 +02:00
parisc	parisc: Enable ARCH_HAS_STRICT_MODULE_RWX	2022-06-29 08:59:53 +02:00
powerpc	powerpc/powernv: delay rng platform device creation until later in boot	2022-07-12 16:32:19 +02:00
riscv	riscv: add as-options for modules with assembly compontents	2022-07-29 17:19:06 +02:00
s390	s390/archrandom: prevent CPACF trng invocations in interrupt context	2022-08-03 12:00:43 +02:00
sh	sh: convert nommu io{re,un}map() to static inline functions	2022-07-21 21:20:02 +02:00
sparc	sparc: use fallback for random_get_entropy() instead of zero	2022-05-30 09:33:42 +02:00
um	um: Add missing apply_returns()	2022-07-25 11:26:55 +02:00
x86	x86/bugs: Do not enable IBPB at firmware entry when IBPB is not available	2022-08-03 12:00:51 +02:00
xtensa	xtensa: Fix refcount leak bug in time.c	2022-06-29 08:59:53 +02:00
.gitignore
Kconfig	arch/cc: Introduce a function to check for confidential computing features	2021-11-18 14:04:32 +01:00