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authorLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 17:54:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 17:54:22 -0700
commitc620f7bd0ba5c882b3e7fc199a8d5c2f6c2f5263 (patch)
treed44e53b3ec7a9cba43540c7e6cea7df3adae5ba2 /Documentation
parentdd4e5d6106b2380e2c1238406d26df8b2fe1c42c (diff)
parentb33f908811b7627015238e0dee9baf2b4c9d720d (diff)
downloadlinux-c620f7bd0ba5c882b3e7fc199a8d5c2f6c2f5263.tar.bz2
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon: "Mostly just incremental improvements here: - Introduce AT_HWCAP2 for advertising CPU features to userspace - Expose SVE2 availability to userspace - Support for "data cache clean to point of deep persistence" (DC PODP) - Honour "mitigations=off" on the cmdline and advertise status via sysfs - CPU timer erratum workaround (Neoverse-N1 #1188873) - Introduce perf PMU driver for the SMMUv3 performance counters - Add config option to disable the kuser helpers page for AArch32 tasks - Futex modifications to ensure liveness under contention - Rework debug exception handling to seperate kernel and user handlers - Non-critical fixes and cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) Documentation: Add ARM64 to kernel-parameters.rst arm64/speculation: Support 'mitigations=' cmdline option arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB arm64: enable generic CPU vulnerabilites support arm64: add sysfs vulnerability show for speculative store bypass arm64: Fix size of __early_cpu_boot_status clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters clocksource/arm_arch_timer: Remove use of workaround static key clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stable clocksource/arm_arch_timer: Direcly assign set_next_event workaround arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvct watchdog/sbsa: Use arch_timer_read_counter instead of arch_counter_get_cntvct ARM: vdso: Remove dependency with the arch_timer driver internals arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1 arm64: Add part number for Neoverse N1 arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32 arm64: mm: Remove pte_unmap_nested() arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable arm64: compat: Reduce address limit for 64K pages ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/admin-guide/kernel-parameters.rst1
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt16
-rw-r--r--Documentation/arm64/cpu-feature-registers.txt16
-rw-r--r--Documentation/arm64/elf_hwcaps.txt41
-rw-r--r--Documentation/arm64/silicon-errata.txt2
-rw-r--r--Documentation/arm64/sve.txt17
-rw-r--r--Documentation/robust-futexes.txt3
7 files changed, 84 insertions, 12 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.rst b/Documentation/admin-guide/kernel-parameters.rst
index b8d0bc07ed0a..0124980dca2d 100644
--- a/Documentation/admin-guide/kernel-parameters.rst
+++ b/Documentation/admin-guide/kernel-parameters.rst
@@ -88,6 +88,7 @@ parameter is applicable::
APIC APIC support is enabled.
APM Advanced Power Management support is enabled.
ARM ARM architecture is enabled.
+ ARM64 ARM64 architecture is enabled.
AX25 Appropriate AX.25 support is enabled.
CLK Common clock infrastructure is enabled.
CMA Contiguous Memory Area support is enabled.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3c0646e28488..fd03e2b629bb 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2548,8 +2548,8 @@
http://repo.or.cz/w/linux-2.6/mini2440.git
mitigations=
- [X86,PPC,S390] Control optional mitigations for CPU
- vulnerabilities. This is a set of curated,
+ [X86,PPC,S390,ARM64] Control optional mitigations for
+ CPU vulnerabilities. This is a set of curated,
arch-independent options, each of which is an
aggregation of existing arch-specific options.
@@ -2558,11 +2558,13 @@
improves system performance, but it may also
expose users to several CPU vulnerabilities.
Equivalent to: nopti [X86,PPC]
+ kpti=0 [ARM64]
nospectre_v1 [PPC]
nobp=0 [S390]
- nospectre_v2 [X86,PPC,S390]
+ nospectre_v2 [X86,PPC,S390,ARM64]
spectre_v2_user=off [X86]
spec_store_bypass_disable=off [X86,PPC]
+ ssbd=force-off [ARM64]
l1tf=off [X86]
auto (default)
@@ -2908,10 +2910,10 @@
check bypass). With this option data leaks are possible
in the system.
- nospectre_v2 [X86,PPC_FSL_BOOK3E] Disable all mitigations for the Spectre variant 2
- (indirect branch prediction) vulnerability. System may
- allow data leaks with this option, which is equivalent
- to spectre_v2=off.
+ nospectre_v2 [X86,PPC_FSL_BOOK3E,ARM64] Disable all mitigations for
+ the Spectre variant 2 (indirect branch prediction)
+ vulnerability. System may allow data leaks with this
+ option.
nospec_store_bypass_disable
[HW] Disable all mitigations for the Speculative Store Bypass vulnerability
diff --git a/Documentation/arm64/cpu-feature-registers.txt b/Documentation/arm64/cpu-feature-registers.txt
index d4b4dd1fe786..684a0da39378 100644
--- a/Documentation/arm64/cpu-feature-registers.txt
+++ b/Documentation/arm64/cpu-feature-registers.txt
@@ -209,6 +209,22 @@ infrastructure:
| AT | [35-32] | y |
x--------------------------------------------------x
+ 6) ID_AA64ZFR0_EL1 - SVE feature ID register 0
+
+ x--------------------------------------------------x
+ | Name | bits | visible |
+ |--------------------------------------------------|
+ | SM4 | [43-40] | y |
+ |--------------------------------------------------|
+ | SHA3 | [35-32] | y |
+ |--------------------------------------------------|
+ | BitPerm | [19-16] | y |
+ |--------------------------------------------------|
+ | AES | [7-4] | y |
+ |--------------------------------------------------|
+ | SVEVer | [3-0] | y |
+ x--------------------------------------------------x
+
Appendix I: Example
---------------------------
diff --git a/Documentation/arm64/elf_hwcaps.txt b/Documentation/arm64/elf_hwcaps.txt
index 13d6691b37be..b73a2519ecf2 100644
--- a/Documentation/arm64/elf_hwcaps.txt
+++ b/Documentation/arm64/elf_hwcaps.txt
@@ -13,9 +13,9 @@ architected discovery mechanism available to userspace code at EL0. The
kernel exposes the presence of these features to userspace through a set
of flags called hwcaps, exposed in the auxilliary vector.
-Userspace software can test for features by acquiring the AT_HWCAP entry
-of the auxilliary vector, and testing whether the relevant flags are
-set, e.g.
+Userspace software can test for features by acquiring the AT_HWCAP or
+AT_HWCAP2 entry of the auxiliary vector, and testing whether the relevant
+flags are set, e.g.
bool floating_point_is_present(void)
{
@@ -135,6 +135,10 @@ HWCAP_DCPOP
Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0001.
+HWCAP2_DCPODP
+
+ Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0010.
+
HWCAP_SHA3
Functionality implied by ID_AA64ISAR0_EL1.SHA3 == 0b0001.
@@ -159,6 +163,30 @@ HWCAP_SVE
Functionality implied by ID_AA64PFR0_EL1.SVE == 0b0001.
+HWCAP2_SVE2
+
+ Functionality implied by ID_AA64ZFR0_EL1.SVEVer == 0b0001.
+
+HWCAP2_SVEAES
+
+ Functionality implied by ID_AA64ZFR0_EL1.AES == 0b0001.
+
+HWCAP2_SVEPMULL
+
+ Functionality implied by ID_AA64ZFR0_EL1.AES == 0b0010.
+
+HWCAP2_SVEBITPERM
+
+ Functionality implied by ID_AA64ZFR0_EL1.BitPerm == 0b0001.
+
+HWCAP2_SVESHA3
+
+ Functionality implied by ID_AA64ZFR0_EL1.SHA3 == 0b0001.
+
+HWCAP2_SVESM4
+
+ Functionality implied by ID_AA64ZFR0_EL1.SM4 == 0b0001.
+
HWCAP_ASIMDFHM
Functionality implied by ID_AA64ISAR0_EL1.FHM == 0b0001.
@@ -194,3 +222,10 @@ HWCAP_PACG
Functionality implied by ID_AA64ISAR1_EL1.GPA == 0b0001 or
ID_AA64ISAR1_EL1.GPI == 0b0001, as described by
Documentation/arm64/pointer-authentication.txt.
+
+
+4. Unused AT_HWCAP bits
+-----------------------
+
+For interoperation with userspace, the kernel guarantees that bits 62
+and 63 of AT_HWCAP will always be returned as 0.
diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt
index d1e2bb801e1b..68d9b74fd751 100644
--- a/Documentation/arm64/silicon-errata.txt
+++ b/Documentation/arm64/silicon-errata.txt
@@ -61,6 +61,7 @@ stable kernels.
| ARM | Cortex-A76 | #1188873 | ARM64_ERRATUM_1188873 |
| ARM | Cortex-A76 | #1165522 | ARM64_ERRATUM_1165522 |
| ARM | Cortex-A76 | #1286807 | ARM64_ERRATUM_1286807 |
+| ARM | Neoverse-N1 | #1188873 | ARM64_ERRATUM_1188873 |
| ARM | MMU-500 | #841119,#826419 | N/A |
| | | | |
| Cavium | ThunderX ITS | #22375, #24313 | CAVIUM_ERRATUM_22375 |
@@ -77,6 +78,7 @@ stable kernels.
| Hisilicon | Hip0{5,6,7} | #161010101 | HISILICON_ERRATUM_161010101 |
| Hisilicon | Hip0{6,7} | #161010701 | N/A |
| Hisilicon | Hip07 | #161600802 | HISILICON_ERRATUM_161600802 |
+| Hisilicon | Hip08 SMMU PMCG | #162001800 | N/A |
| | | | |
| Qualcomm Tech. | Kryo/Falkor v1 | E1003 | QCOM_FALKOR_ERRATUM_1003 |
| Qualcomm Tech. | Falkor v1 | E1009 | QCOM_FALKOR_ERRATUM_1009 |
diff --git a/Documentation/arm64/sve.txt b/Documentation/arm64/sve.txt
index 7169a0ec41d8..9940e924a47e 100644
--- a/Documentation/arm64/sve.txt
+++ b/Documentation/arm64/sve.txt
@@ -34,6 +34,23 @@ model features for SVE is included in Appendix A.
following sections: software that needs to verify that those interfaces are
present must check for HWCAP_SVE instead.
+* On hardware that supports the SVE2 extensions, HWCAP2_SVE2 will also
+ be reported in the AT_HWCAP2 aux vector entry. In addition to this,
+ optional extensions to SVE2 may be reported by the presence of:
+
+ HWCAP2_SVE2
+ HWCAP2_SVEAES
+ HWCAP2_SVEPMULL
+ HWCAP2_SVEBITPERM
+ HWCAP2_SVESHA3
+ HWCAP2_SVESM4
+
+ This list may be extended over time as the SVE architecture evolves.
+
+ These extensions are also reported via the CPU ID register ID_AA64ZFR0_EL1,
+ which userspace can read using an MRS instruction. See elf_hwcaps.txt and
+ cpu-feature-registers.txt for details.
+
* Debuggers should restrict themselves to interacting with the target via the
NT_ARM_SVE regset. The recommended way of detecting support for this regset
is to connect to a target process first and then attempt a
diff --git a/Documentation/robust-futexes.txt b/Documentation/robust-futexes.txt
index 6c42c75103eb..6361fb01c9c1 100644
--- a/Documentation/robust-futexes.txt
+++ b/Documentation/robust-futexes.txt
@@ -218,5 +218,4 @@ All other architectures should build just fine too - but they won't have
the new syscalls yet.
Architectures need to implement the new futex_atomic_cmpxchg_inatomic()
-inline function before writing up the syscalls (that function returns
--ENOSYS right now).
+inline function before writing up the syscalls.