Warning messages are printed and ignored if we use an unsupported option

When an unsupported limit on cgroups V1 rootless systems
is requested, podman prints an warning message and
ignores the option/flag.

```
  Target options/flags:
    --cpu-period, --cpu-quota, --cpu-rt-period, --cpu-rt-runtime,
    --cpus, --cpu-shares, --cpuset-cpus, --cpuset-mems, --memory,
    --memory-reservation, --memory-swap, --memory-swappiness,
    --blkio-weight, --device-read-bps, --device-write-bps,
    --device-read-iops, --device-write-iops, --blkio-weight-device
```

Related to https://github.com/containers/podman/discussions/10152

Signed-off-by: Toshiki Sonoda <sonoda.toshiki@fujitsu.com>

18 files changed, 78 insertions, 4 deletions

diff --git a/docs/source/markdown/options/blkio-weight.md b/docs/source/markdown/options/blkio-weight.md
index eb8e94144..04a1071c0 100644
--- a/docs/source/markdown/options/blkio-weight.md
+++ b/docs/source/markdown/options/blkio-weight.md
@@ -1,3 +1,5 @@
 #### **--blkio-weight**=*weight*
 
 Block IO relative weight. The _weight_ is a value between **10** and **1000**.
+
+This option is not supported on cgroups V1 rootless systems.
diff --git a/docs/source/markdown/options/cpu-period.md b/docs/source/markdown/options/cpu-period.md
index efbe6c2ab..5c5eb56e7 100644
--- a/docs/source/markdown/options/cpu-period.md
+++ b/docs/source/markdown/options/cpu-period.md
@@ -8,3 +8,5 @@ microseconds.
 On some systems, changing the resource limits may not be allowed for non-root
 users. For more details, see
 https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-with-resource-limits-fails-with-a-permissions-error
+
+This option is not supported on cgroups V1 rootless systems.
diff --git a/docs/source/markdown/options/cpu-quota.md b/docs/source/markdown/options/cpu-quota.md
index 753797bad..81d5db3d2 100644
--- a/docs/source/markdown/options/cpu-quota.md
+++ b/docs/source/markdown/options/cpu-quota.md
@@ -10,3 +10,5 @@ ends (controllable via **--cpu-period**).
 On some systems, changing the resource limits may not be allowed for non-root
 users. For more details, see
 https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-with-resource-limits-fails-with-a-permissions-error
+
+This option is not supported on cgroups V1 rootless systems.
diff --git a/docs/source/markdown/options/cpu-rt-period.md b/docs/source/markdown/options/cpu-rt-period.md
index 9014beb33..36e88632e 100644
--- a/docs/source/markdown/options/cpu-rt-period.md
+++ b/docs/source/markdown/options/cpu-rt-period.md
@@ -4,4 +4,4 @@ Limit the CPU real-time period in microseconds.
 
 Limit the container's Real Time CPU usage. This option tells the kernel to restrict the container's Real Time CPU usage to the period specified.
 
-This option is not supported on cgroups V2 systems.
+This option is only supported on cgroups V1 rootful systems.
diff --git a/docs/source/markdown/options/cpu-rt-runtime.md b/docs/source/markdown/options/cpu-rt-runtime.md
index 05b1d3b96..64f0ec38b 100644
--- a/docs/source/markdown/options/cpu-rt-runtime.md
+++ b/docs/source/markdown/options/cpu-rt-runtime.md
@@ -7,4 +7,4 @@ Period of 1,000,000us and Runtime of 950,000us means that this container could c
 
 The sum of all runtimes across containers cannot exceed the amount allotted to the parent cgroup.
 
-This option is not supported on cgroups V2 systems.
+This option is only supported on cgroups V1 rootful systems.
diff --git a/docs/source/markdown/options/cpu-shares.md b/docs/source/markdown/options/cpu-shares.md
index c2115c1bf..c0e2c3035 100644
--- a/docs/source/markdown/options/cpu-shares.md
+++ b/docs/source/markdown/options/cpu-shares.md
@@ -37,3 +37,5 @@ this can result in the following division of CPU shares:
 On some systems, changing the resource limits may not be allowed for non-root
 users. For more details, see
 https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-with-resource-limits-fails-with-a-permissions-error
+
+This option is not supported on cgroups V1 rootless systems.
diff --git a/docs/source/markdown/options/cpuset-cpus.md b/docs/source/markdown/options/cpuset-cpus.md
index a67766897..8a2a82e9f 100644
--- a/docs/source/markdown/options/cpuset-cpus.md
+++ b/docs/source/markdown/options/cpuset-cpus.md
@@ -7,3 +7,5 @@ CPUs in which to allow execution. Can be specified as a comma-separated list
 On some systems, changing the resource limits may not be allowed for non-root
 users. For more details, see
 https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-with-resource-limits-fails-with-a-permissions-error
+
+This option is not supported on cgroups V1 rootless systems.
diff --git a/docs/source/markdown/options/cpuset-mems.md b/docs/source/markdown/options/cpuset-mems.md
index 1eeab7b13..b86d0ef6b 100644
--- a/docs/source/markdown/options/cpuset-mems.md
+++ b/docs/source/markdown/options/cpuset-mems.md
@@ -10,3 +10,5 @@ two memory nodes.
 On some systems, changing the resource limits may not be allowed for non-root
 users. For more details, see
 https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-with-resource-limits-fails-with-a-permissions-error
+
+This option is not supported on cgroups V1 rootless systems.
diff --git a/docs/source/markdown/options/memory-swappiness.md b/docs/source/markdown/options/memory-swappiness.md
index 65f0ef310..1e6a51188 100644
--- a/docs/source/markdown/options/memory-swappiness.md
+++ b/docs/source/markdown/options/memory-swappiness.md
@@ -2,4 +2,4 @@
 
 Tune a container's memory swappiness behavior. Accepts an integer between *0* and *100*.
 
-This flag is not supported on cgroups V2 systems.
+This flag is only supported on cgroups V1 rootful systems.
diff --git a/docs/source/markdown/podman-container-clone.1.md.in b/docs/source/markdown/podman-container-clone.1.md.in
index cf760d7a2..26f414b62 100644
--- a/docs/source/markdown/podman-container-clone.1.md.in
+++ b/docs/source/markdown/podman-container-clone.1.md.in
@@ -40,6 +40,8 @@ Set a number of CPUs for the container that overrides the original containers CP
 This is shorthand
 for **--cpu-period** and **--cpu-quota**, so only **--cpus** or either both the **--cpu-period** and **--cpu-quota** options can be set.
 
+This option is not supported on cgroups V1 rootless systems.
+
 @@option cpuset-cpus
 
 If none are specified, the original container's CPUset is used.
@@ -54,10 +56,14 @@ If none are specified, the original container's CPU memory nodes are used.
 
 Limit read rate (bytes per second) from a device (e.g. --device-read-bps=/dev/sda:1mb).
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--device-write-bps**=*path*
 
 Limit write rate (bytes per second) to a device (e.g. --device-write-bps=/dev/sda:1mb)
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--force**, **-f**
 
 Force removal of the original container that we are cloning. Can only be used in conjunction with **--destroy**.
@@ -74,6 +80,8 @@ system's page size (the value would be very large, that's millions of trillions)
 
 If no memory limits are specified, the original container's will be used.
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--memory-reservation**=*limit*
 
 Memory soft limit (format: `<number>[<unit>]`, where unit = b (bytes), k (kibibytes), m (mebibytes), or g (gibibytes))
@@ -84,6 +92,8 @@ reservation. So you should always set the value below **--memory**, otherwise th
 hard limit will take precedence. By default, memory reservation will be the same
 as memory limit from the container being cloned.
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--memory-swap**=*limit*
 
 A limit value equal to memory plus swap. Must be used with the  **-m**
@@ -95,6 +105,8 @@ The format of `LIMIT` is `<number>[<unit>]`. Unit can be `b` (bytes),
 `k` (kibibytes), `m` (mebibytes), or `g` (gibibytes). If you don't specify a
 unit, `b` is used. Set LIMIT to `-1` to enable unlimited swap.
 
+This option is not supported on cgroups V1 rootless systems.
+
 @@option memory-swappiness
 
 #### **--name**
diff --git a/docs/source/markdown/podman-create.1.md.in b/docs/source/markdown/podman-create.1.md.in
index 7ec4fc66f..74348ac7d 100644
--- a/docs/source/markdown/podman-create.1.md.in
+++ b/docs/source/markdown/podman-create.1.md.in
@@ -131,6 +131,8 @@ On some systems, changing the CPU limits may not be allowed for non-root
 users. For more details, see
 https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-with-cpu-limits-fails-with-a-permissions-error
 
+This option is not supported on cgroups V1 rootless systems.
+
 @@option cpuset-cpus
 
 @@option cpuset-mems
@@ -165,18 +167,26 @@ Add a rule to the cgroup allowed devices list. The rule is expected to be in the
 
 Limit read rate (bytes per second) from a device (e.g. --device-read-bps=/dev/sda:1mb)
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--device-read-iops**=*path*
 
 Limit read rate (IO per second) from a device (e.g. --device-read-iops=/dev/sda:1000)
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--device-write-bps**=*path*
 
 Limit write rate (bytes per second) to a device (e.g. --device-write-bps=/dev/sda:1mb)
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--device-write-iops**=*path*
 
 Limit write rate (IO per second) to a device (e.g. --device-write-iops=/dev/sda:1000)
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--disable-content-trust**
 
 This is a Docker specific option to disable image verification to a Docker
@@ -366,6 +376,8 @@ RAM. If a limit of 0 is specified (not using **-m**), the container's memory is
 not limited. The actual limit may be rounded up to a multiple of the operating
 system's page size (the value would be very large, that's millions of trillions).
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--memory-reservation**=*limit*
 
 Memory soft limit (format: `<number>[<unit>]`, where unit = b (bytes), k (kibibytes), m (mebibytes), or g (gibibytes))
@@ -376,6 +388,8 @@ reservation. So you should always set the value below **--memory**, otherwise th
 hard limit will take precedence. By default, memory reservation will be the same
 as memory limit.
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--memory-swap**=*limit*
 
 A limit value equal to memory plus swap. Must be used with the  **-m**
@@ -387,6 +401,8 @@ The format of `LIMIT` is `<number>[<unit>]`. Unit can be `b` (bytes),
 `k` (kibibytes), `m` (mebibytes), or `g` (gibibytes). If you don't specify a
 unit, `b` is used. Set LIMIT to `-1` to enable unlimited swap.
 
+This option is not supported on cgroups V1 rootless systems.
+
 @@option memory-swappiness
 
 @@option mount
diff --git a/docs/source/markdown/podman-run.1.md.in b/docs/source/markdown/podman-run.1.md.in
index d10520e35..e943ec005 100644
--- a/docs/source/markdown/podman-run.1.md.in
+++ b/docs/source/markdown/podman-run.1.md.in
@@ -146,6 +146,8 @@ On some systems, changing the CPU limits may not be allowed for non-root
 users. For more details, see
 https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-with-cpu-limits-fails-with-a-permissions-error
 
+This option is not supported on cgroups V1 rootless systems.
+
 @@option cpuset-cpus
 
 @@option cpuset-mems
@@ -196,18 +198,26 @@ Add a rule to the cgroup allowed devices list
 
 Limit read rate (in bytes per second) from a device (e.g. **--device-read-bps=/dev/sda:1mb**).
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--device-read-iops**=*path:rate*
 
 Limit read rate (in IO operations per second) from a device (e.g. **--device-read-iops=/dev/sda:1000**).
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--device-write-bps**=*path:rate*
 
 Limit write rate (in bytes per second) to a device (e.g. **--device-write-bps=/dev/sda:1mb**).
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--device-write-iops**=*path:rate*
 
 Limit write rate (in IO operations per second) to a device (e.g. **--device-write-iops=/dev/sda:1000**).
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--disable-content-trust**
 
 This is a Docker specific option to disable image verification to a Docker
@@ -377,6 +387,8 @@ RAM. If a limit of 0 is specified (not using **-m**), the container's memory is
 not limited. The actual limit may be rounded up to a multiple of the operating
 system's page size (the value would be very large, that's millions of trillions).
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--memory-reservation**=*number[unit]*
 
 Memory soft limit. A _unit_ can be **b** (bytes), **k** (kibibytes), **m** (mebibytes), or **g** (gibibytes).
@@ -387,6 +399,8 @@ reservation. So you should always set the value below **--memory**, otherwise th
 hard limit will take precedence. By default, memory reservation will be the same
 as memory limit.
 
+This option is not supported on cgroups V1 rootless systems.
+
 #### **--memory-swap**=*number[unit]*
 
 A limit value equal to memory plus swap.
@@ -399,6 +413,8 @@ the value of **--memory**.
 
 Set _number_ to **-1** to enable unlimited swap.
 
+This option is not supported on cgroups V1 rootless systems.
+
 @@option memory-swappiness
 
 @@option mount
diff --git a/pkg/specgen/generate/validate.go b/pkg/specgen/generate/validate.go
index 9c933d747..3c5d5fb96 100644
--- a/pkg/specgen/generate/validate.go
+++ b/pkg/specgen/generate/validate.go
@@ -9,6 +9,7 @@ import (
 
 	"github.com/containers/common/pkg/cgroups"
 	"github.com/containers/common/pkg/sysinfo"
+	"github.com/containers/podman/v4/pkg/rootless"
 	"github.com/containers/podman/v4/pkg/specgen"
 	"github.com/containers/podman/v4/utils"
 )
@@ -19,6 +20,11 @@ func verifyContainerResourcesCgroupV1(s *specgen.SpecGenerator) ([]string, error
 
 	sysInfo := sysinfo.New(true)
 
+	if s.ResourceLimits != nil && rootless.IsRootless() {
+		s.ResourceLimits = nil
+		warnings = append(warnings, "Resource limits are not supported and ignored on cgroups V1 rootless systems")
+	}
+
 	if s.ResourceLimits == nil {
 		return warnings, nil
 	}
diff --git a/test/e2e/container_clone_test.go b/test/e2e/container_clone_test.go
index 94ccd6ffe..d7641e42a 100644
--- a/test/e2e/container_clone_test.go
+++ b/test/e2e/container_clone_test.go
@@ -87,6 +87,7 @@ var _ = Describe("Podman container clone", func() {
 	})
 
 	It("podman container clone resource limits override", func() {
+		SkipIfRootlessCgroupsV1("Not supported for rootless + CgroupsV1")
 		create := podmanTest.Podman([]string{"create", "--cpus=5", ALPINE})
 		create.WaitWithDefaultTimeout()
 		Expect(create).To(Exit(0))
diff --git a/test/e2e/create_test.go b/test/e2e/create_test.go
index 9679aad24..b35d0f3c5 100644
--- a/test/e2e/create_test.go
+++ b/test/e2e/create_test.go
@@ -438,6 +438,7 @@ var _ = Describe("Podman create", func() {
 	})
 
 	It("podman create with -m 1000000 sets swap to 2000000", func() {
+		SkipIfRootlessCgroupsV1("Not supported for rootless + CgroupsV1")
 		numMem := 1000000
 		ctrName := "testCtr"
 		session := podmanTest.Podman([]string{"create", "-t", "-m", fmt.Sprintf("%db", numMem), "--name", ctrName, ALPINE, "/bin/sh"})
@@ -452,6 +453,7 @@ var _ = Describe("Podman create", func() {
 	})
 
 	It("podman create --cpus 5 sets nanocpus", func() {
+		SkipIfRootlessCgroupsV1("Not supported for rootless + CgroupsV1")
 		numCpus := 5
 		nanoCPUs := numCpus * 1000000000
 		ctrName := "testCtr"
diff --git a/test/e2e/generate_kube_test.go b/test/e2e/generate_kube_test.go
index 142f32d19..e7ceaf2d2 100644
--- a/test/e2e/generate_kube_test.go
+++ b/test/e2e/generate_kube_test.go
@@ -490,6 +490,7 @@ var _ = Describe("Podman generate kube", func() {
 	})
 
 	It("podman generate kube on pod with memory limit", func() {
+		SkipIfRootlessCgroupsV1("Not supported for rootless + CgroupsV1")
 		podName := "testMemoryLimit"
 		podSession := podmanTest.Podman([]string{"pod", "create", "--name", podName})
 		podSession.WaitWithDefaultTimeout()
@@ -515,6 +516,7 @@ var _ = Describe("Podman generate kube", func() {
 	})
 
 	It("podman generate kube on pod with cpu limit", func() {
+		SkipIfRootlessCgroupsV1("Not supported for rootless + CgroupsV1")
 		podName := "testCpuLimit"
 		podSession := podmanTest.Podman([]string{"pod", "create", "--name", podName})
 		podSession.WaitWithDefaultTimeout()
diff --git a/test/e2e/generate_spec_test.go b/test/e2e/generate_spec_test.go
index 57cd9546b..9188b5222 100644
--- a/test/e2e/generate_spec_test.go
+++ b/test/e2e/generate_spec_test.go
@@ -41,6 +41,7 @@ var _ = Describe("Podman generate spec", func() {
 	})
 
 	It("podman generate spec basic usage", func() {
+		SkipIfRootlessCgroupsV1("Not supported for rootless + CgroupsV1")
 		session := podmanTest.Podman([]string{"create", "--cpus", "5", "--name", "specgen", ALPINE})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
@@ -51,6 +52,7 @@ var _ = Describe("Podman generate spec", func() {
 	})
 
 	It("podman generate spec file", func() {
+		SkipIfRootlessCgroupsV1("Not supported for rootless + CgroupsV1")
 		session := podmanTest.Podman([]string{"create", "--cpus", "5", "--name", "specgen", ALPINE})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
diff --git a/test/system/030-run.bats b/test/system/030-run.bats
index 908c169ee..a3bfe5780 100644
--- a/test/system/030-run.bats
+++ b/test/system/030-run.bats
@@ -56,7 +56,12 @@ echo $rand        |   0 | $rand
 
 @test "podman run --memory=0 runtime option" {
     run_podman run --memory=0 --rm $IMAGE echo hello
-    is "$output" "hello" "failed to run when --memory is set to 0"
+    if is_rootless && ! is_cgroupsv2; then
+        is "${lines[0]}" "Resource limits are not supported and ignored on cgroups V1 rootless systems" "--memory is not supported"
+        is "${lines[1]}" "hello" "--memory is ignored"
+    else
+        is "$output" "hello" "failed to run when --memory is set to 0"
+    fi
 }
 
 # 'run --preserve-fds' passes a number of additional file descriptors into the container