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authorLibravatar dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>2023-01-09 08:10:55 +0000
committerLibravatar GitHub <noreply@github.com>2023-01-09 08:10:55 +0000
commit345b765a46d7646f6597698a95cf0f3b1915448d (patch)
treee38a76109513c35a64e8f71a27facd81bc6f213d /vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go
parent[bugfix] return early in websocket upgrade handler (#1315) (diff)
downloadgotosocial-345b765a46d7646f6597698a95cf0f3b1915448d.tar.xz
[chore]: Bump golang.org/x/net from 0.4.0 to 0.5.0 (#1319)
Bumps [golang.org/x/net](https://github.com/golang/net) from 0.4.0 to 0.5.0. - [Release notes](https://github.com/golang/net/releases) - [Commits](https://github.com/golang/net/compare/v0.4.0...v0.5.0) --- updated-dependencies: - dependency-name: golang.org/x/net dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Diffstat (limited to 'vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go')
-rw-r--r--vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go44
1 files changed, 42 insertions, 2 deletions
diff --git a/vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go b/vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go
index 79a38a0b9..a968b80fa 100644
--- a/vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go
+++ b/vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go
@@ -4,6 +4,11 @@
package cpu
+import (
+ "strings"
+ "syscall"
+)
+
// HWCAP/HWCAP2 bits. These are exposed by Linux.
const (
hwcap_FP = 1 << 0
@@ -32,10 +37,45 @@ const (
hwcap_ASIMDFHM = 1 << 23
)
+// linuxKernelCanEmulateCPUID reports whether we're running
+// on Linux 4.11+. Ideally we'd like to ask the question about
+// whether the current kernel contains
+// https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=77c97b4ee21290f5f083173d957843b615abbff2
+// but the version number will have to do.
+func linuxKernelCanEmulateCPUID() bool {
+ var un syscall.Utsname
+ syscall.Uname(&un)
+ var sb strings.Builder
+ for _, b := range un.Release[:] {
+ if b == 0 {
+ break
+ }
+ sb.WriteByte(byte(b))
+ }
+ major, minor, _, ok := parseRelease(sb.String())
+ return ok && (major > 4 || major == 4 && minor >= 11)
+}
+
func doinit() {
if err := readHWCAP(); err != nil {
- // failed to read /proc/self/auxv, try reading registers directly
- readARM64Registers()
+ // We failed to read /proc/self/auxv. This can happen if the binary has
+ // been given extra capabilities(7) with /bin/setcap.
+ //
+ // When this happens, we have two options. If the Linux kernel is new
+ // enough (4.11+), we can read the arm64 registers directly which'll
+ // trap into the kernel and then return back to userspace.
+ //
+ // But on older kernels, such as Linux 4.4.180 as used on many Synology
+ // devices, calling readARM64Registers (specifically getisar0) will
+ // cause a SIGILL and we'll die. So for older kernels, parse /proc/cpuinfo
+ // instead.
+ //
+ // See golang/go#57336.
+ if linuxKernelCanEmulateCPUID() {
+ readARM64Registers()
+ } else {
+ readLinuxProcCPUInfo()
+ }
return
}