kernel-selftest: Add a recipe on kernel selftest

The recipe builds the framework for kernel-selftest. Now, it just
contains two sets of testcase, bpf and vm. We will append more to
this recipe.

The following kernel config fragments must be manually enabled,
i.e. in local.conf, to use this test suite.
KERNEL_FEATURES_append += "features/bpf/bpf.scc \
                        cfg/debug-kselftest.scc \
                   features/hugetlb/hugetlb.scc \
"

Signed-off-by: Hongzhi.Song <hongzhi.song@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

5 files changed, 833 insertions, 0 deletions

diff --git a/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest.bb b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest.bb
new file mode 100644
index 000000000..27d98a304
--- /dev/null
+++ b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest.bb
@@ -0,0 +1,104 @@
+SUMMARY = "Kernel selftest for Linux"
+DESCRIPTION = "Kernel selftest for Linux"
+LICENSE = "GPLv2"
+
+LIC_FILES_CHKSUM = "file://COPYING;md5=d7810fab7487fb0aad327b76f1be7cd7 \
+"
+
+# for musl libc
+SRC_URI_libc-musl += "file://userfaultfd.patch \
+                      file://0001-bpf-test_progs.c-add-support-for-musllibc.patch \
+"
+
+PACKAGECONFIG ??= "bpf vm"
+
+PACKAGECONFIG[bpf] = ",,elfutils libcap libcap-ng rsync-native,"
+PACKAGECONFIG[vm] = ",,,libgcc bash"
+
+do_patch[depends] += "virtual/kernel:do_shared_workdir"
+
+inherit linux-kernel-base kernel-arch
+
+do_populate_lic[depends] += "virtual/kernel:do_patch"
+
+S = "${WORKDIR}/${BP}"
+
+# now we just test bpf and vm
+# we will append other kernel selftest in the future
+TEST_LIST = "bpf \
+             vm \
+"
+
+EXTRA_OEMAKE = '\
+    CROSS_COMPILE=${TARGET_PREFIX} \
+    ARCH=${ARCH} \
+    CC="${CC}" \
+    AR="${AR}" \
+    LD="${LD}" \
+'
+
+EXTRA_OEMAKE += "\
+    'DESTDIR=${D}' \
+"
+
+KERNEL_SELFTEST_SRC ?= "Makefile \
+                        include \
+                        tools \
+                        scripts \
+                        arch \
+                        COPYING \
+"
+
+python __anonymous () {
+    import re
+
+    var = d.getVar('TARGET_CC_ARCH')
+    pattern = '_FORTIFY_SOURCE=[^0]'
+
+    if re.search(pattern, var):
+        d.appendVar('TARGET_CC_ARCH', " -O")
+}
+
+do_compile() {
+    for i in ${TEST_LIST}
+    do
+        oe_runmake -C ${S}/tools/testing/selftests/${i}
+    done
+}
+
+do_install() {
+    for i in ${TEST_LIST}
+    do
+        oe_runmake -C ${S}/tools/testing/selftests/${i} INSTALL_PATH=${D}/usr/kernel-selftest/${i} install
+    done
+
+    chown root:root  -R ${D}/usr/kernel-selftest
+}
+
+do_configure() {
+    :
+}
+
+do_patch[prefuncs] += "copy_kselftest_source_from_kernel remove_clang_related"
+python copy_kselftest_source_from_kernel() {
+    sources = (d.getVar("KERNEL_SELFTEST_SRC") or "").split()
+    src_dir = d.getVar("STAGING_KERNEL_DIR")
+    dest_dir = d.getVar("S")
+    bb.utils.mkdirhier(dest_dir)
+    for s in sources:
+        src = oe.path.join(src_dir, s)
+        dest = oe.path.join(dest_dir, s)
+        if os.path.isdir(src):
+            oe.path.copytree(src, dest)
+        else:
+            bb.utils.copyfile(src, dest)
+}
+
+remove_clang_related() {
+        sed -i -e '/test_pkt_access/d' -e '/test_pkt_md_access/d' ${S}/tools/testing/selftests/bpf/Makefile
+}
+
+PACKAGE_ARCH = "${MACHINE_ARCH}"
+
+INHIBIT_PACKAGE_DEBUG_SPLIT="1"
+FILES_${PN} += "/usr/kernel-selftest"
diff --git a/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/0001-bpf-test_progs.c-add-support-for-musllibc.patch b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/0001-bpf-test_progs.c-add-support-for-musllibc.patch
new file mode 100644
index 000000000..5f2542681
--- /dev/null
+++ b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/0001-bpf-test_progs.c-add-support-for-musllibc.patch
@@ -0,0 +1,25 @@
+From a2e6b8fde28b743b69990a4e16c296e099631ed4 Mon Sep 17 00:00:00 2001
+From: "Hongzhi.Song" <hongzhi.song@windriver.com>
+Date: Mon, 23 Jul 2018 00:56:19 -0700
+Subject: [PATCH] bpf: test_progs.c add support for musllibc
+
+Signed-off-by: Hongzhi.Song <hongzhi.song@windriver.com>
+---
+ tools/testing/selftests/bpf/test_progs.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
+index 11ee25c..21b27b7 100644
+--- a/tools/testing/selftests/bpf/test_progs.c
++++ b/tools/testing/selftests/bpf/test_progs.c
+@@ -4,6 +4,7 @@
+  * modify it under the terms of version 2 of the GNU General Public
+  * License as published by the Free Software Foundation.
+  */
++#define __always_inline __inline __attribute__ ((__always_inline__))
+ #include <stdio.h>
+ #include <unistd.h>
+ #include <errno.h>
+-- 
+2.11.0
+
diff --git a/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/0001-swap.h-micro-define-to-support-musl-libc.patch b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/0001-swap.h-micro-define-to-support-musl-libc.patch
new file mode 100644
index 000000000..e2245fc4c
--- /dev/null
+++ b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/0001-swap.h-micro-define-to-support-musl-libc.patch
@@ -0,0 +1,26 @@
+From c21dfb0dfdfec281479e267ad7fe9a8d4ba15a70 Mon Sep 17 00:00:00 2001
+From: "Hongzhi.Song" <hongzhi.song@windriver.com>
+Date: Tue, 17 Jul 2018 23:47:48 -0700
+Subject: [PATCH] add micro define to support musl libc
+
+Signed-off-by: Hongzhi.Song <hongzhi.song@windriver.com>
+---
+ recipe-sysroot/usr/include/linux/swab.h | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/recipe-sysroot/usr/include/linux/swab.h b/recipe-sysroot/usr/include/linux/swab.h
+index afb7eb7..33efa10 100644
+--- a/recipe-sysroot/usr/include/linux/swab.h
++++ b/recipe-sysroot/usr/include/linux/swab.h
+@@ -6,6 +6,8 @@
+ 
+ #include <asm/swab.h>
+ 
++#define __always_inline __inline __attribute__ ((__always_inline__))
++
+ /*
+  * casts are necessary for constants, because we never know how for sure
+  * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way.
+-- 
+2.11.0
+
diff --git a/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/COPYING b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/COPYING
new file mode 100644
index 000000000..ca442d313
--- /dev/null
+++ b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/COPYING
@@ -0,0 +1,356 @@
+
+   NOTE! This copyright does *not* cover user programs that use kernel
+ services by normal system calls - this is merely considered normal use
+ of the kernel, and does *not* fall under the heading of "derived work".
+ Also note that the GPL below is copyrighted by the Free Software
+ Foundation, but the instance of code that it refers to (the Linux
+ kernel) is copyrighted by me and others who actually wrote it.
+
+ Also note that the only valid version of the GPL as far as the kernel
+ is concerned is _this_ particular version of the license (ie v2, not
+ v2.2 or v3.x or whatever), unless explicitly otherwise stated.
+
+                        Linus Torvalds
+
+----------------------------------------
+
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+
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diff --git a/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/userfaultfd.patch b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/userfaultfd.patch
new file mode 100644
index 000000000..bed20510e
--- /dev/null
+++ b/meta-oe/recipes-kernel/kernel-selftest/kernel-selftest/userfaultfd.patch
@@ -0,0 +1,322 @@
+From c7b375747cffb627d02543d946b28525455d7d46 Mon Sep 17 00:00:00 2001
+From: "Hongzhi.Song" <hongzhi.song@windriver.com>
+Date: Fri, 13 Jul 2018 06:06:19 -0700
+Subject: [PATCH] vm: add some funtions to support musl libc
+
+Signed-off-by: Hongzhi.Song <hongzhi.song@windriver.com>
+---
+ tools/testing/selftests/vm/userfaultfd.c | 298 +++++++++++++++++++++++++++++++
+ 1 file changed, 298 insertions(+)
+
+diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c
+index de2f9ec..dc73021 100644
+--- a/tools/testing/selftests/vm/userfaultfd.c
++++ b/tools/testing/selftests/vm/userfaultfd.c
+@@ -71,6 +71,304 @@
+ 
+ #ifdef __NR_userfaultfd
+ 
++/* Linear congruential.  */
++#define        TYPE_0          0
++#define        BREAK_0         8
++#define        DEG_0           0
++#define        SEP_0           0
++
++/* x**7 + x**3 + 1.  */
++#define        TYPE_1          1
++#define        BREAK_1         32
++#define        DEG_1           7
++#define        SEP_1           3
++
++/* x**15 + x + 1.  */
++#define        TYPE_2          2
++#define        BREAK_2         64
++#define        DEG_2           15
++#define        SEP_2           1
++
++/* x**31 + x**3 + 1.  */
++#define        TYPE_3          3
++#define        BREAK_3         128
++#define        DEG_3           31
++#define        SEP_3           3
++
++/* x**63 + x + 1.  */
++#define        TYPE_4          4
++#define        BREAK_4         256
++#define        DEG_4           63
++#define        SEP_4           1
++
++/* Array versions of the above information to make code run faster.
++   Relies on fact that TYPE_i == i.  */
++
++#define        MAX_TYPES       5       /* Max number of types above.  */
++
++#define __set_errno(val) (errno = (val))
++
++struct random_data
++  {
++    int32_t *fptr;      /* Front pointer.  */
++    int32_t *rptr;      /* Rear pointer.  */
++    int32_t *state;     /* Array of state values.  */
++    int rand_type;      /* Type of random number generator.  */
++    int rand_deg;       /* Degree of random number generator.  */
++    int rand_sep;       /* Distance between front and rear.  */
++    int32_t *end_ptr;       /* Pointer behind state table.  */
++  };
++
++struct random_poly_info
++{
++  int seps[MAX_TYPES];
++  int degrees[MAX_TYPES];
++};
++
++static const struct random_poly_info random_poly_info =
++{
++  { SEP_0, SEP_1, SEP_2, SEP_3, SEP_4 },
++  { DEG_0, DEG_1, DEG_2, DEG_3, DEG_4 }
++};
++
++/* If we are using the trivial TYPE_0 R.N.G., just do the old linear
++   congruential bit.  Otherwise, we do our fancy trinomial stuff, which is the
++   same in all the other cases due to all the global variables that have been
++   set up.  The basic operation is to add the number at the rear pointer into
++   the one at the front pointer.  Then both pointers are advanced to the next
++   location cyclically in the table.  The value returned is the sum generated,
++   reduced to 31 bits by throwing away the "least random" low bit.
++   Note: The code takes advantage of the fact that both the front and
++   rear pointers can't wrap on the same call by not testing the rear
++   pointer if the front one has wrapped.  Returns a 31-bit random number.  */
++
++int random_r (struct random_data *buf, int32_t *result)
++{
++  int32_t *state;
++
++  if (buf == NULL || result == NULL)
++    goto fail;
++
++  state = buf->state;
++
++  if (buf->rand_type == TYPE_0)
++    {
++      int32_t val = ((state[0] * 1103515245U) + 12345U) & 0x7fffffff;
++      state[0] = val;
++      *result = val;
++    }
++  else
++    {
++      int32_t *fptr = buf->fptr;
++      int32_t *rptr = buf->rptr;
++      int32_t *end_ptr = buf->end_ptr;
++      uint32_t val;
++
++      val = *fptr += (uint32_t) *rptr;
++      /* Chucking least random bit.  */
++      *result = val >> 1;
++      ++fptr;
++      if (fptr >= end_ptr)
++       {
++         fptr = state;
++         ++rptr;
++       }
++      else
++       {
++         ++rptr;
++         if (rptr >= end_ptr)
++           rptr = state;
++       }
++      buf->fptr = fptr;
++      buf->rptr = rptr;
++    }
++  return 0;
++
++ fail:
++  __set_errno (EINVAL);
++  return -1;
++}
++
++/* Initialize the random number generator based on the given seed.  If the
++   type is the trivial no-state-information type, just remember the seed.
++   Otherwise, initializes state[] based on the given "seed" via a linear
++   congruential generator.  Then, the pointers are set to known locations
++   that are exactly rand_sep places apart.  Lastly, it cycles the state
++   information a given number of times to get rid of any initial dependencies
++   introduced by the L.C.R.N.G.  Note that the initialization of randtbl[]
++   for default usage relies on values produced by this routine.  */
++int srandom_r (unsigned int seed, struct random_data *buf)
++{
++  int type;
++  int32_t *state;
++  long int i;
++  int32_t word;
++  int32_t *dst;
++  int kc;
++
++  if (buf == NULL)
++    goto fail;
++  type = buf->rand_type;
++  if ((unsigned int) type >= MAX_TYPES)
++    goto fail;
++
++  state = buf->state;
++  /* We must make sure the seed is not 0.  Take arbitrarily 1 in this case.  */
++  if (seed == 0)
++    seed = 1;
++  state[0] = seed;
++  if (type == TYPE_0)
++    goto done;
++
++  dst = state;
++  word = seed;
++  kc = buf->rand_deg;
++  for (i = 1; i < kc; ++i)
++    {
++      /* This does:
++          state[i] = (16807 * state[i - 1]) % 2147483647;
++        but avoids overflowing 31 bits.  */
++      long int hi = word / 127773;
++      long int lo = word % 127773;
++      word = 16807 * lo - 2836 * hi;
++      if (word < 0)
++       word += 2147483647;
++      *++dst = word;
++    }
++
++  buf->fptr = &state[buf->rand_sep];
++  buf->rptr = &state[0];
++  kc *= 10;
++  while (--kc >= 0)
++    {
++      int32_t discard;
++      (void) random_r (buf, &discard);
++    }
++
++ done:
++  return 0;
++
++ fail:
++  return -1;
++}
++
++/* Initialize the state information in the given array of N bytes for
++   future random number generation.  Based on the number of bytes we
++   are given, and the break values for the different R.N.G.'s, we choose
++   the best (largest) one we can and set things up for it.  srandom is
++   then called to initialize the state information.  Note that on return
++   from srandom, we set state[-1] to be the type multiplexed with the current
++   value of the rear pointer; this is so successive calls to initstate won't
++   lose this information and will be able to restart with setstate.
++   Note: The first thing we do is save the current state, if any, just like
++   setstate so that it doesn't matter when initstate is called.
++   Returns 0 on success, non-zero on failure.  */
++int initstate_r (unsigned int seed, char *arg_state, size_t n,
++              struct random_data *buf)
++{
++  if (buf == NULL)
++    goto fail;
++
++  int32_t *old_state = buf->state;
++  if (old_state != NULL)
++    {
++      int old_type = buf->rand_type;
++      if (old_type == TYPE_0)
++       old_state[-1] = TYPE_0;
++      else
++       old_state[-1] = (MAX_TYPES * (buf->rptr - old_state)) + old_type;
++    }
++
++  int type;
++  if (n >= BREAK_3)
++    type = n < BREAK_4 ? TYPE_3 : TYPE_4;
++  else if (n < BREAK_1)
++    {
++      if (n < BREAK_0)
++       goto fail;
++
++      type = TYPE_0;
++    }
++  else
++    type = n < BREAK_2 ? TYPE_1 : TYPE_2;
++
++  int degree = random_poly_info.degrees[type];
++  int separation = random_poly_info.seps[type];
++
++  buf->rand_type = type;
++  buf->rand_sep = separation;
++  buf->rand_deg = degree;
++  int32_t *state = &((int32_t *) arg_state)[1];        /* First location.  */
++  /* Must set END_PTR before srandom.  */
++  buf->end_ptr = &state[degree];
++
++  buf->state = state;
++
++  srandom_r (seed, buf);
++
++  state[-1] = TYPE_0;
++  if (type != TYPE_0)
++    state[-1] = (buf->rptr - state) * MAX_TYPES + type;
++
++  return 0;
++
++ fail:
++  __set_errno (EINVAL);
++  return -1;
++}
++
++/* Restore the state from the given state array.
++   Note: It is important that we also remember the locations of the pointers
++   in the current state information, and restore the locations of the pointers
++   from the old state information.  This is done by multiplexing the pointer
++   location into the zeroth word of the state information. Note that due
++   to the order in which things are done, it is OK to call setstate with the
++   same state as the current state
++   Returns 0 on success, non-zero on failure.  */
++int setstate_r (char *arg_state, struct random_data *buf)
++{
++  int32_t *new_state = 1 + (int32_t *) arg_state;
++  int type;
++  int old_type;
++  int32_t *old_state;
++  int degree;
++  int separation;
++
++  if (arg_state == NULL || buf == NULL)
++    goto fail;
++
++  old_type = buf->rand_type;
++  old_state = buf->state;
++  if (old_type == TYPE_0)
++    old_state[-1] = TYPE_0;
++  else
++    old_state[-1] = (MAX_TYPES * (buf->rptr - old_state)) + old_type;
++
++  type = new_state[-1] % MAX_TYPES;
++  if (type < TYPE_0 || type > TYPE_4)
++    goto fail;
++
++  buf->rand_deg = degree = random_poly_info.degrees[type];
++  buf->rand_sep = separation = random_poly_info.seps[type];
++  buf->rand_type = type;
++
++  if (type != TYPE_0)
++    {
++      int rear = new_state[-1] / MAX_TYPES;
++      buf->rptr = &new_state[rear];
++      buf->fptr = &new_state[(rear + separation) % degree];
++    }
++  buf->state = new_state;
++  /* Set end_ptr too.  */
++  buf->end_ptr = &new_state[degree];
++
++  return 0;
++
++ fail:
++  __set_errno (EINVAL);
++  return -1;
++}
++
+ static unsigned long nr_cpus, nr_pages, nr_pages_per_cpu, page_size;
+ 
+ #define BOUNCE_RANDOM          (1<<0)
+-- 
+2.11.0
+