Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Allow booting of late secondary CPUs affected by erratum 1418040
(currently they are parked if none of the early CPUs are affected by
this erratum).
- Add the 32-bit vdso Makefile to the vdso_install rule so that 'make
vdso_install' installs the 32-bit compat vdso when it is compiled.
- Print a warning that untrusted guests without a CPU erratum
workaround (Cortex-A57 832075) may deadlock the affected system.
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
ARM64: vdso32: Install vdso32 from vdso_install
KVM: arm64: Print warning when cpu erratum can cause guests to deadlock
arm64: Allow booting of late CPUs affected by erratum 1418040
arm64: Move handling of erratum 1418040 into C code
+42
-22
+1
arch/arm64/Makefile
+1
arch/arm64/Makefile
+2
arch/arm64/kernel/cpu_errata.c
+2
arch/arm64/kernel/cpu_errata.c
···
910
910
.desc = "ARM erratum 1418040",
911
911
.capability = ARM64_WORKAROUND_1418040,
912
912
ERRATA_MIDR_RANGE_LIST(erratum_1418040_list),
913
+
.type = (ARM64_CPUCAP_SCOPE_LOCAL_CPU |
914
+
ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU),
913
915
},
914
916
#endif
915
917
#ifdef CONFIG_ARM64_WORKAROUND_SPECULATIVE_AT
-21
arch/arm64/kernel/entry.S
-21
arch/arm64/kernel/entry.S
···
170
170
stp x28, x29, [sp, #16 * 14]
171
171
172
172
.if \el == 0
173
-
.if \regsize == 32
174
-
/*
175
-
* If we're returning from a 32-bit task on a system affected by
176
-
* 1418040 then re-enable userspace access to the virtual counter.
177
-
*/
178
-
#ifdef CONFIG_ARM64_ERRATUM_1418040
179
-
alternative_if ARM64_WORKAROUND_1418040
180
-
mrs x0, cntkctl_el1
181
-
orr x0, x0, #2 // ARCH_TIMER_USR_VCT_ACCESS_EN
182
-
msr cntkctl_el1, x0
183
-
alternative_else_nop_endif
184
-
#endif
185
-
.endif
186
173
clear_gp_regs
187
174
mrs x21, sp_el0
188
175
ldr_this_cpu tsk, __entry_task, x20
···
280
293
msr sp_el0, x23
281
294
tst x22, #PSR_MODE32_BIT // native task?
282
295
b.eq 3f
283
-
284
-
#ifdef CONFIG_ARM64_ERRATUM_1418040
285
-
alternative_if ARM64_WORKAROUND_1418040
286
-
mrs x0, cntkctl_el1
287
-
bic x0, x0, #2 // ARCH_TIMER_USR_VCT_ACCESS_EN
288
-
msr cntkctl_el1, x0
289
-
alternative_else_nop_endif
290
-
#endif
291
296
292
297
#ifdef CONFIG_ARM64_ERRATUM_845719
293
298
alternative_if ARM64_WORKAROUND_845719
+34
arch/arm64/kernel/process.c
+34
arch/arm64/kernel/process.c
···
516
516
}
517
517
518
518
/*
519
+
* ARM erratum 1418040 handling, affecting the 32bit view of CNTVCT.
520
+
* Assuming the virtual counter is enabled at the beginning of times:
521
+
*
522
+
* - disable access when switching from a 64bit task to a 32bit task
523
+
* - enable access when switching from a 32bit task to a 64bit task
524
+
*/
525
+
static void erratum_1418040_thread_switch(struct task_struct *prev,
526
+
struct task_struct *next)
527
+
{
528
+
bool prev32, next32;
529
+
u64 val;
530
+
531
+
if (!(IS_ENABLED(CONFIG_ARM64_ERRATUM_1418040) &&
532
+
cpus_have_const_cap(ARM64_WORKAROUND_1418040)))
533
+
return;
534
+
535
+
prev32 = is_compat_thread(task_thread_info(prev));
536
+
next32 = is_compat_thread(task_thread_info(next));
537
+
538
+
if (prev32 == next32)
539
+
return;
540
+
541
+
val = read_sysreg(cntkctl_el1);
542
+
543
+
if (!next32)
544
+
val |= ARCH_TIMER_USR_VCT_ACCESS_EN;
545
+
else
546
+
val &= ~ARCH_TIMER_USR_VCT_ACCESS_EN;
547
+
548
+
write_sysreg(val, cntkctl_el1);
549
+
}
550
+
551
+
/*
519
552
* Thread switching.
520
553
*/
521
554
__notrace_funcgraph struct task_struct *__switch_to(struct task_struct *prev,
···
563
530
entry_task_switch(next);
564
531
uao_thread_switch(next);
565
532
ssbs_thread_switch(next);
533
+
erratum_1418040_thread_switch(prev, next);
566
534
567
535
/*
568
536
* Complete any pending TLB or cache maintenance on this CPU in case
+1
-1
arch/arm64/kernel/vdso32/Makefile
+1
-1
arch/arm64/kernel/vdso32/Makefile
···
208
208
cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
209
209
210
210
# Install commands for the unstripped file
211
-
quiet_cmd_vdso_install = INSTALL $@
211
+
quiet_cmd_vdso_install = INSTALL32 $@
212
212
cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/vdso32.so
213
213
214
214
vdso.so: $(obj)/vdso.so.dbg
+4
arch/arm64/kvm/arm.c
+4
arch/arm64/kvm/arm.c
···
1640
1640
return -ENODEV;
1641
1641
}
1642
1642
1643
+
if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE))
1644
+
kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
1645
+
"Only trusted guests should be used on this system.\n");
1646
+
1643
1647
for_each_online_cpu(cpu) {
1644
1648
smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1);
1645
1649
if (ret < 0) {