Merge pull request #1946 from fidencio/wip/weekly-backports-to-stable-2.1

[stable-2.1] Weekly backports to stable-2.1 branch, May 31st 2021

src/agent/rustjail/src/cgroups/fs/mod.rs

@@ -349,14 +349,34 @@ fn set_memory_resources(cg: &cgroups::Cgroup, memory: &LinuxMemory, update: bool
         mem_controller.set_kmem_limit(-1)?;
     }
 
-    set_resource!(mem_controller, set_limit, memory, limit);
-    set_resource!(mem_controller, set_soft_limit, memory, reservation);
-    set_resource!(mem_controller, set_kmem_limit, memory, kernel);
-    set_resource!(mem_controller, set_tcp_limit, memory, kernel_tcp);
+    // If the memory update is set to -1 we should also
+    // set swap to -1, it means unlimited memory.
+    let mut swap = memory.swap.unwrap_or(0);
+    if memory.limit == Some(-1) {
+        swap = -1;
+    }
 
-    if let Some(swap) = memory.swap {
-        // set memory swap
-        let swap = if cg.v2() {
+    if memory.limit.is_some() && swap != 0 {
+        let memstat = get_memory_stats(cg)
+            .into_option()
+            .ok_or_else(|| anyhow!("failed to get the cgroup memory stats"))?;
+        let memusage = memstat.get_usage();
+
+        // When update memory limit, the kernel would check the current memory limit
+        // set against the new swap setting, if the current memory limit is large than
+        // the new swap, then set limit first, otherwise the kernel would complain and
+        // refused to set; on the other hand, if the current memory limit is smaller than
+        // the new swap, then we should set the swap first and then set the memor limit.
+        if swap == -1 || memusage.get_limit() < swap as u64 {
+            mem_controller.set_memswap_limit(swap)?;
+            set_resource!(mem_controller, set_limit, memory, limit);
+        } else {
+            set_resource!(mem_controller, set_limit, memory, limit);
+            mem_controller.set_memswap_limit(swap)?;
+        }
+    } else {
+        set_resource!(mem_controller, set_limit, memory, limit);
+        swap = if cg.v2() {
             convert_memory_swap_to_v2_value(swap, memory.limit.unwrap_or(0))?
         } else {
             swap
@@ -366,6 +386,10 @@ fn set_memory_resources(cg: &cgroups::Cgroup, memory: &LinuxMemory, update: bool
         }
     }
 
+    set_resource!(mem_controller, set_soft_limit, memory, reservation);
+    set_resource!(mem_controller, set_kmem_limit, memory, kernel);
+    set_resource!(mem_controller, set_tcp_limit, memory, kernel_tcp);
+
     if let Some(swappiness) = memory.swappiness {
         if (0..=100).contains(&swappiness) {
             mem_controller.set_swappiness(swappiness as u64)?;

src/agent/src/main.rs

@@ -248,6 +248,7 @@ fn main() -> std::result::Result<(), Box<dyn std::error::Error>> {
     }
 
     if args.len() == 2 && args[1] == "init" {
+        reset_sigpipe();
         rustjail::container::init_child();
         exit(0);
     }
@@ -358,5 +359,16 @@ fn sethostname(hostname: &OsStr) -> Result<()> {
     }
 }
 
+// The Rust standard library had suppressed the default SIGPIPE behavior,
+// see https://github.com/rust-lang/rust/pull/13158.
+// Since the parent's signal handler would be inherited by it's child process,
+// thus we should re-enable the standard SIGPIPE behavior as a workaround to
+// fix the issue of https://github.com/kata-containers/kata-containers/issues/1887.
+fn reset_sigpipe() {
+    unsafe {
+        libc::signal(libc::SIGPIPE, libc::SIG_DFL);
+    }
+}
+
 use crate::config::AgentConfig;
 use std::os::unix::io::{FromRawFd, RawFd};

src/runtime/virtcontainers/virtiofsd.go

@@ -75,6 +75,8 @@ func (v *virtiofsd) getSocketFD() (*os.File, error) {
 	if err != nil {
 		return nil, err
 	}
+
+	// no longer needed since fd is a dup
 	defer listener.Close()
 
 	listener.SetUnlinkOnClose(false)
@@ -98,6 +100,7 @@ func (v *virtiofsd) Start(ctx context.Context) (int, error) {
 	if err != nil {
 		return 0, err
 	}
+	defer socketFD.Close()
 
 	cmd.ExtraFiles = append(cmd.ExtraFiles, socketFD)
 
@@ -128,7 +131,7 @@ func (v *virtiofsd) Start(ctx context.Context) (int, error) {
 		v.wait = waitVirtiofsReady
 	}
 
-	return pid, socketFD.Close()
+	return cmd.Process.Pid, nil
 }
 
 func (v *virtiofsd) Stop(ctx context.Context) error {