| Message ID | 20190515134731.12611-3-krzesimir@kinvolk.io |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf,v1,1/3] selftests/bpf: Test correctness of narrow 32bitread on 64bit field | expand |
On Wed, 15 May 2019 15:47:27 +0200, Krzesimir Nowak wrote: > This prints a message when the error is about program type being not > supported by the test runner or because of permissions problem. This > is to see if the program we expected to run was actually executed. > > The messages are open-coded because strerror(ENOTSUPP) returns > "Unknown error 524". > > Signed-off-by: Krzesimir Nowak <krzesimir@kinvolk.io> > --- > tools/testing/selftests/bpf/test_verifier.c | 17 +++++++++++++---- > 1 file changed, 13 insertions(+), 4 deletions(-) > > diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c > index ccd896b98cac..bf0da03f593b 100644 > --- a/tools/testing/selftests/bpf/test_verifier.c > +++ b/tools/testing/selftests/bpf/test_verifier.c > @@ -825,11 +825,20 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val, > tmp, &size_tmp, &retval, NULL); > if (unpriv) > set_admin(false); > - if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) { > - printf("Unexpected bpf_prog_test_run error "); > - return err; > + if (err) { > + switch (errno) { > + case 524/*ENOTSUPP*/: > + printf("Did not run the program (not supported) "); > + return 0; > + case EPERM: > + printf("Did not run the program (no permission) "); > + return 0; Perhaps use strerror(errno)? > + default: > + printf("Unexpected bpf_prog_test_run error "); > + return err; > + } > } > - if (!err && retval != expected_val && > + if (retval != expected_val && > expected_val != POINTER_VALUE) { > printf("FAIL retval %d != %d ", retval, expected_val); > return 1;
On Wed, May 15, 2019 at 11:46 PM Jakub Kicinski <jakub.kicinski@netronome.com> wrote: > > On Wed, 15 May 2019 15:47:27 +0200, Krzesimir Nowak wrote: > > This prints a message when the error is about program type being not > > supported by the test runner or because of permissions problem. This > > is to see if the program we expected to run was actually executed. > > > > The messages are open-coded because strerror(ENOTSUPP) returns > > "Unknown error 524". > > > > Signed-off-by: Krzesimir Nowak <krzesimir@kinvolk.io> > > --- > > tools/testing/selftests/bpf/test_verifier.c | 17 +++++++++++++---- > > 1 file changed, 13 insertions(+), 4 deletions(-) > > > > diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c > > index ccd896b98cac..bf0da03f593b 100644 > > --- a/tools/testing/selftests/bpf/test_verifier.c > > +++ b/tools/testing/selftests/bpf/test_verifier.c > > @@ -825,11 +825,20 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val, > > tmp, &size_tmp, &retval, NULL); > > if (unpriv) > > set_admin(false); > > - if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) { > > - printf("Unexpected bpf_prog_test_run error "); > > - return err; > > + if (err) { > > + switch (errno) { > > + case 524/*ENOTSUPP*/: > > + printf("Did not run the program (not supported) "); > > + return 0; > > + case EPERM: > > + printf("Did not run the program (no permission) "); > > + return 0; > > Perhaps use strerror(errno)? As I said in the commit message, I open-coded those messages because strerror for ENOTSUPP returns "Unknown error 524". > > > + default: > > + printf("Unexpected bpf_prog_test_run error "); > > + return err; > > + } > > } > > - if (!err && retval != expected_val && > > + if (retval != expected_val && > > expected_val != POINTER_VALUE) { > > printf("FAIL retval %d != %d ", retval, expected_val); > > return 1; >
On Thu, 16 May 2019 11:29:39 +0200, Krzesimir Nowak wrote: > > > diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c > > > index ccd896b98cac..bf0da03f593b 100644 > > > --- a/tools/testing/selftests/bpf/test_verifier.c > > > +++ b/tools/testing/selftests/bpf/test_verifier.c > > > @@ -825,11 +825,20 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val, > > > tmp, &size_tmp, &retval, NULL); > > > if (unpriv) > > > set_admin(false); > > > - if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) { > > > - printf("Unexpected bpf_prog_test_run error "); > > > - return err; > > > + if (err) { > > > + switch (errno) { > > > + case 524/*ENOTSUPP*/: > > > + printf("Did not run the program (not supported) "); > > > + return 0; > > > + case EPERM: > > > + printf("Did not run the program (no permission) "); > > > + return 0; > > > > Perhaps use strerror(errno)? > > As I said in the commit message, I open-coded those messages because > strerror for ENOTSUPP returns "Unknown error 524". Ah, sorry, missed that. I wonder if that's something worth addressing in libc, since the BPF subsystem uses ENOTSUPP a lot.
On Thu, May 16, 2019 at 5:51 PM Jakub Kicinski <jakub.kicinski@netronome.com> wrote: > > On Thu, 16 May 2019 11:29:39 +0200, Krzesimir Nowak wrote: > > > > diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c > > > > index ccd896b98cac..bf0da03f593b 100644 > > > > --- a/tools/testing/selftests/bpf/test_verifier.c > > > > +++ b/tools/testing/selftests/bpf/test_verifier.c > > > > @@ -825,11 +825,20 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val, > > > > tmp, &size_tmp, &retval, NULL); > > > > if (unpriv) > > > > set_admin(false); > > > > - if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) { > > > > - printf("Unexpected bpf_prog_test_run error "); > > > > - return err; > > > > + if (err) { > > > > + switch (errno) { > > > > + case 524/*ENOTSUPP*/: > > > > + printf("Did not run the program (not supported) "); > > > > + return 0; > > > > + case EPERM: > > > > + printf("Did not run the program (no permission) "); > > > > + return 0; > > > > > > Perhaps use strerror(errno)? > > > > As I said in the commit message, I open-coded those messages because > > strerror for ENOTSUPP returns "Unknown error 524". > > Ah, sorry, missed that. I wonder if that's something worth addressing > in libc, since the BPF subsystem uses ENOTSUPP a lot. The "not supported" errno situation seems to be a mess. There is an ENOTSUP define in libc. ENOTSUP is usually defined to be EOPNOTSUPP (taken from kernel), which in turn seems to have a different value (95) than kernel's ENOTSUPP (524). Adding ENOTSUPP (with two Ps) to libc would only add to the confusion. So it's kind of meh and I guess people just moved on with workarounds.
On Thu, 16 May 2019 18:21:32 +0200, Krzesimir Nowak wrote: > On Thu, May 16, 2019 at 5:51 PM Jakub Kicinski wrote: > > On Thu, 16 May 2019 11:29:39 +0200, Krzesimir Nowak wrote: > > > > > diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c > > > > > index ccd896b98cac..bf0da03f593b 100644 > > > > > --- a/tools/testing/selftests/bpf/test_verifier.c > > > > > +++ b/tools/testing/selftests/bpf/test_verifier.c > > > > > @@ -825,11 +825,20 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val, > > > > > tmp, &size_tmp, &retval, NULL); > > > > > if (unpriv) > > > > > set_admin(false); > > > > > - if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) { > > > > > - printf("Unexpected bpf_prog_test_run error "); > > > > > - return err; > > > > > + if (err) { > > > > > + switch (errno) { > > > > > + case 524/*ENOTSUPP*/: > > > > > + printf("Did not run the program (not supported) "); > > > > > + return 0; > > > > > + case EPERM: > > > > > + printf("Did not run the program (no permission) "); > > > > > + return 0; > > > > > > > > Perhaps use strerror(errno)? > > > > > > As I said in the commit message, I open-coded those messages because > > > strerror for ENOTSUPP returns "Unknown error 524". > > > > Ah, sorry, missed that. I wonder if that's something worth addressing > > in libc, since the BPF subsystem uses ENOTSUPP a lot. > > The "not supported" errno situation seems to be a mess. There is an > ENOTSUP define in libc. ENOTSUP is usually defined to be EOPNOTSUPP > (taken from kernel), which in turn seems to have a different value > (95) than kernel's ENOTSUPP (524). Adding ENOTSUPP (with two Ps) to > libc would only add to the confusion. So it's kind of meh and I guess > people just moved on with workarounds. Yes, ENOTSUP is never used in the kernel, but it's a mess. This commit a while ago said ENOTSUPP is from NFS: commit 423b3aecf29085a52530d4f9167c56a84b081042 Author: Or Gerlitz <ogerlitz@mellanox.com> Date: Thu Feb 23 12:02:41 2017 +0200 net/mlx4: Change ENOTSUPP to EOPNOTSUPP As ENOTSUPP is specific to NFS, change the return error value to EOPNOTSUPP in various places in the mlx4 driver. Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Suggested-by: Yotam Gigi <yotamg@mellanox.com> Reviewed-by: Matan Barak <matanb@mellanox.com> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> But it's spreading throughout the kernel like a wildfire, I counted 1364 in my tree :/ Some are in tools/, but still. My understanding was that system calls should never return values above 512, but I'm probably wrong about that. Given the popularity, and the fact its an ABI at this point, we probably have no choice but to add it to libc, but to be clear IMO it's not a blocker for your patches.
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index ccd896b98cac..bf0da03f593b 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -825,11 +825,20 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val, tmp, &size_tmp, &retval, NULL); if (unpriv) set_admin(false); - if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) { - printf("Unexpected bpf_prog_test_run error "); - return err; + if (err) { + switch (errno) { + case 524/*ENOTSUPP*/: + printf("Did not run the program (not supported) "); + return 0; + case EPERM: + printf("Did not run the program (no permission) "); + return 0; + default: + printf("Unexpected bpf_prog_test_run error "); + return err; + } } - if (!err && retval != expected_val && + if (retval != expected_val && expected_val != POINTER_VALUE) { printf("FAIL retval %d != %d ", retval, expected_val); return 1;
This prints a message when the error is about program type being not supported by the test runner or because of permissions problem. This is to see if the program we expected to run was actually executed. The messages are open-coded because strerror(ENOTSUPP) returns "Unknown error 524". Signed-off-by: Krzesimir Nowak <krzesimir@kinvolk.io> --- tools/testing/selftests/bpf/test_verifier.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-)