Minor formatting updates for gvisor.dev.

* Aggregate architecture Overview in "What is gVisor?" as it makes more sense
  in one place.

* Drop "user-space kernel" and use "application kernel". The term "user-space
  kernel" is confusing when some platform implementation do not run in
  user-space (instead running in guest ring zero).

* Clear up the relationship between the Platform page in the user guide and the
  Platform page in the architecture guide, and ensure they are cross-linked.

* Restore the call-to-action quick start link in the main page, and drop the
  GitHub link (which also appears in the top-right).

* Improve image formatting by centering all doc and blog images, and move the
  image captions to the alt text.

PiperOrigin-RevId: 311845158

1 files changed, 2 insertions, 2 deletions

diff --git a/pkg/sentry/kernel/task_syscall.go b/pkg/sentry/kernel/task_syscall.go
index c9db78e06..a5903b0b5 100644
--- a/pkg/sentry/kernel/task_syscall.go
+++ b/pkg/sentry/kernel/task_syscall.go
@@ -199,10 +199,10 @@ func (t *Task) doSyscall() taskRunState {
 	//
 	// On x86, register rax was shared by syscall number and return
 	// value, and at the entry of the syscall handler, the rax was
-	// saved to regs.orig_rax which was exposed to user space.
+	// saved to regs.orig_rax which was exposed to userspace.
 	// But on arm64, syscall number was passed through X8, and the X0
 	// was shared by the first syscall argument and return value. The
-	// X0 was saved to regs.orig_x0 which was not exposed to user space.
+	// X0 was saved to regs.orig_x0 which was not exposed to userspace.
 	// So we have to do the same operation here to save the X0 value
 	// into the task context.
 	t.Arch().SyscallSaveOrig()