Exercise some basic functionality of the new xc_{get,set}_p2m_mempool_size()
hypercalls.

This passes on x86, but fails currently on ARM.  ARM will be fixed up in
future patches.

This is part of XSA-409 / CVE-2022-33747.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Xen Security Team <security@xen.org>
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>
CC: Wei Liu <wl@xen.org>
CC: Stefano Stabellini <sstabellini@kernel.org>
CC: Julien Grall <julien@xen.org>
CC: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
CC: Bertrand Marquis <bertrand.marquis@arm.com>
CC: Henry Wang <Henry.Wang@arm.com>
CC: Anthony PERARD <anthony.perard@citrix.com>
---
 tools/tests/Makefile                 |   1 +
 tools/tests/p2m-pool/.gitignore      |   1 +
 tools/tests/p2m-pool/Makefile        |  42 ++++++++
 tools/tests/p2m-pool/test-p2m-pool.c | 181 +++++++++++++++++++++++++++++++++++
 4 files changed, 225 insertions(+)
 create mode 100644 tools/tests/p2m-pool/.gitignore
 create mode 100644 tools/tests/p2m-pool/Makefile
 create mode 100644 tools/tests/p2m-pool/test-p2m-pool.c

diff --git a/tools/tests/Makefile b/tools/tests/Makefile
index d99146d56a64..7ce8b7b881db 100644
--- a/tools/tests/Makefile
+++ b/tools/tests/Makefile
@@ -11,6 +11,7 @@ endif
 SUBDIRS-y += xenstore
 SUBDIRS-y += depriv
 SUBDIRS-y += vpci
+SUBDIRS-y += p2m-pool
 
 .PHONY: all clean install distclean uninstall
 all clean distclean install uninstall: %: subdirs-%
diff --git a/tools/tests/p2m-pool/.gitignore b/tools/tests/p2m-pool/.gitignore
new file mode 100644
index 000000000000..cce6d97b1cc8
--- /dev/null
+++ b/tools/tests/p2m-pool/.gitignore
@@ -0,0 +1 @@
+test-p2m-pool
diff --git a/tools/tests/p2m-pool/Makefile b/tools/tests/p2m-pool/Makefile
new file mode 100644
index 000000000000..24f348f20582
--- /dev/null
+++ b/tools/tests/p2m-pool/Makefile
@@ -0,0 +1,42 @@
+XEN_ROOT = $(CURDIR)/../../..
+include $(XEN_ROOT)/tools/Rules.mk
+
+TARGET := test-p2m-pool
+
+.PHONY: all
+all: $(TARGET)
+
+.PHONY: clean
+clean:
+	$(RM) -- *.o $(TARGET) $(DEPS_RM)
+
+.PHONY: distclean
+distclean: clean
+	$(RM) -- *~
+
+.PHONY: install
+install: all
+	$(INSTALL_DIR) $(DESTDIR)$(LIBEXEC_BIN)
+	$(INSTALL_PROG) $(TARGET) $(DESTDIR)$(LIBEXEC_BIN)
+
+.PHONY: uninstall
+uninstall:
+	$(RM) -- $(DESTDIR)$(LIBEXEC_BIN)/$(TARGET)
+
+CFLAGS += $(CFLAGS_xeninclude)
+CFLAGS += $(CFLAGS_libxenctrl)
+CFLAGS += $(CFLAGS_libxenforeginmemory)
+CFLAGS += $(CFLAGS_libxengnttab)
+CFLAGS += $(APPEND_CFLAGS)
+
+LDFLAGS += $(LDLIBS_libxenctrl)
+LDFLAGS += $(LDLIBS_libxenforeignmemory)
+LDFLAGS += $(LDLIBS_libxengnttab)
+LDFLAGS += $(APPEND_LDFLAGS)
+
+%.o: Makefile
+
+$(TARGET): test-p2m-pool.o
+	$(CC) -o $@ $< $(LDFLAGS)
+
+-include $(DEPS_INCLUDE)
diff --git a/tools/tests/p2m-pool/test-p2m-pool.c b/tools/tests/p2m-pool/test-p2m-pool.c
new file mode 100644
index 000000000000..1ffb19eeb420
--- /dev/null
+++ b/tools/tests/p2m-pool/test-p2m-pool.c
@@ -0,0 +1,181 @@
+#include <err.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <xenctrl.h>
+#include <xenforeignmemory.h>
+#include <xengnttab.h>
+#include <xen-tools/libs.h>
+
+static unsigned int nr_failures;
+#define fail(fmt, ...)                          \
+({                                              \
+    nr_failures++;                              \
+    (void)printf(fmt, ##__VA_ARGS__);           \
+})
+
+static xc_interface *xch;
+static uint32_t domid;
+
+static struct xen_domctl_createdomain create = {
+    .flags = XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap,
+    .max_vcpus = 1,
+    .max_grant_frames = 1,
+    .grant_opts = XEN_DOMCTL_GRANT_version(1),
+
+    .arch = {
+#if defined(__x86_64__) || defined(__i386__)
+        .emulation_flags = XEN_X86_EMU_LAPIC,
+#endif
+    },
+};
+
+static uint64_t default_p2m_size_bytes =
+#if defined(__x86_64__) || defined(__i386__)
+    256 << 12; /* Only x86 HAP for now.  x86 Shadow broken. */
+#elif defined (__arm__) || defined(__aarch64__)
+    16 << 12;
+#endif
+
+static void run_tests(void)
+{
+    xen_pfn_t physmap[] = { 0 };
+    uint64_t size_bytes, old_size_bytes;
+    int rc;
+
+    printf("Test default p2m mempool size\n");
+
+    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
+    if ( rc )
+        return fail("  Fail: get p2m mempool size: %d - %s\n",
+                    errno, strerror(errno));
+
+    printf("P2M pool size %"PRIu64" bytes (%"PRIu64"kB, %"PRIu64"MB)\n",
+           size_bytes, size_bytes >> 10, size_bytes >> 20);
+
+
+    /*
+     * Check that the domain has the expected default allocation size.  This
+     * will fail if the logic in Xen is altered without an equivelent
+     * adjustment here.
+     */
+    if ( size_bytes != default_p2m_size_bytes )
+        return fail("  Fail: size %"PRIu64" != expected size %"PRIu64"\n",
+                    size_bytes, default_p2m_size_bytes);
+
+
+    printf("Test that allocate doesn't alter pool size\n");
+
+    /*
+     * Populate the domain with some RAM.  This will cause more of the p2m
+     * pool to be used.
+     */
+    old_size_bytes = size_bytes;
+
+    rc = xc_domain_setmaxmem(xch, domid, -1);
+    if ( rc )
+        return fail("  Fail: setmaxmem: : %d - %s\n",
+                    errno, strerror(errno));
+
+    rc = xc_domain_populate_physmap_exact(xch, domid, 1, 0, 0, physmap);
+    if ( rc )
+        return fail("  Fail: populate physmap: %d - %s\n",
+                    errno, strerror(errno));
+
+    /*
+     * Re-get the p2m size.  Should not have changed as a consequence of
+     * populate physmap.
+     */
+    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
+    if ( rc )
+        return fail("  Fail: get p2m mempool size: %d - %s\n",
+                    errno, strerror(errno));
+
+    if ( old_size_bytes != size_bytes )
+        return fail("  Fail: p2m mempool size changed %"PRIu64" => %"PRIu64"\n",
+                    old_size_bytes, size_bytes);
+
+
+
+    printf("Test bad set size\n");
+
+    /*
+     * Check that setting a non-page size results in failure.
+     */
+    rc = xc_set_p2m_mempool_size(xch, domid, size_bytes + 1);
+    if ( rc != -1 || errno != EINVAL )
+        return fail("  Fail: Bad set size: expected -1/EINVAL, got %d/%d - %s\n",
+                    rc, errno, strerror(errno));
+
+
+    printf("Test very large set size\n");
+
+    /*
+     * Check that setting a large P2M size succeeds.  This is expecting to
+     * trigger continuations.
+     */
+    rc = xc_set_p2m_mempool_size(xch, domid, 64 << 20);
+    if ( rc )
+        return fail("  Fail: Set size 64MB: %d - %s\n",
+                    errno, strerror(errno));
+
+
+    /*
+     * Check that the reported size matches what set consumed.
+     */
+    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
+    if ( rc )
+        return fail("  Fail: get p2m mempool size: %d - %s\n",
+                    errno, strerror(errno));
+
+    if ( size_bytes != 64 << 20 )
+        return fail("  Fail: expected mempool size %u, got %"PRIu64"\n",
+                    64 << 20, size_bytes);
+}
+
+int main(int argc, char **argv)
+{
+    int rc;
+
+    printf("P2M Shadow memory pool tests\n");
+
+    xch = xc_interface_open(NULL, NULL, 0);
+
+    if ( !xch )
+        err(1, "xc_interface_open");
+
+    rc = xc_domain_create(xch, &domid, &create);
+    if ( rc )
+    {
+        if ( errno == EINVAL || errno == EOPNOTSUPP )
+            printf("  Skip: %d - %s\n", errno, strerror(errno));
+        else
+            fail("  Domain create failure: %d - %s\n",
+                 errno, strerror(errno));
+        goto out;
+    }
+
+    printf("  Created d%u\n", domid);
+
+    run_tests();
+
+    rc = xc_domain_destroy(xch, domid);
+    if ( rc )
+        fail("  Failed to destroy domain: %d - %s\n",
+             errno, strerror(errno));
+ out:
+    return !!nr_failures;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
-- 
2.11.0

On 26.10.2022 12:20, Andrew Cooper wrote:
> --- /dev/null
> +++ b/tools/tests/p2m-pool/Makefile
> @@ -0,0 +1,42 @@
> +XEN_ROOT = $(CURDIR)/../../..
> +include $(XEN_ROOT)/tools/Rules.mk
> +
> +TARGET := test-p2m-pool
> +
> +.PHONY: all
> +all: $(TARGET)
> +
> +.PHONY: clean
> +clean:
> +	$(RM) -- *.o $(TARGET) $(DEPS_RM)
> +
> +.PHONY: distclean
> +distclean: clean
> +	$(RM) -- *~
> +
> +.PHONY: install
> +install: all
> +	$(INSTALL_DIR) $(DESTDIR)$(LIBEXEC_BIN)
> +	$(INSTALL_PROG) $(TARGET) $(DESTDIR)$(LIBEXEC_BIN)
> +
> +.PHONY: uninstall
> +uninstall:
> +	$(RM) -- $(DESTDIR)$(LIBEXEC_BIN)/$(TARGET)
> +
> +CFLAGS += $(CFLAGS_xeninclude)
> +CFLAGS += $(CFLAGS_libxenctrl)
> +CFLAGS += $(CFLAGS_libxenforeginmemory)

Typo here or typo also elsewhere: CFLAGS_libxenforeignmemory? I
have to admit that I can't really spot where these variables are
populated. The place in Rules.mk that I could spot uses

 CFLAGS_libxen$(1) = $$(CFLAGS_xeninclude)

i.e. the expansion doesn't really depend on the library.

Apart from this looks okay to me, maybe apart from ...

> --- /dev/null
> +++ b/tools/tests/p2m-pool/test-p2m-pool.c
> @@ -0,0 +1,181 @@
> +#include <err.h>
> +#include <errno.h>
> +#include <inttypes.h>
> +#include <stdio.h>
> +#include <string.h>
> +#include <sys/mman.h>
> +
> +#include <xenctrl.h>
> +#include <xenforeignmemory.h>
> +#include <xengnttab.h>
> +#include <xen-tools/libs.h>
> +
> +static unsigned int nr_failures;
> +#define fail(fmt, ...)                          \
> +({                                              \
> +    nr_failures++;                              \
> +    (void)printf(fmt, ##__VA_ARGS__);           \
> +})
> +
> +static xc_interface *xch;
> +static uint32_t domid;
> +
> +static struct xen_domctl_createdomain create = {
> +    .flags = XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap,
> +    .max_vcpus = 1,
> +    .max_grant_frames = 1,
> +    .grant_opts = XEN_DOMCTL_GRANT_version(1),
> +
> +    .arch = {
> +#if defined(__x86_64__) || defined(__i386__)
> +        .emulation_flags = XEN_X86_EMU_LAPIC,
> +#endif
> +    },
> +};
> +
> +static uint64_t default_p2m_size_bytes =
> +#if defined(__x86_64__) || defined(__i386__)
> +    256 << 12; /* Only x86 HAP for now.  x86 Shadow broken. */

... this shadow related comment (the commit message could at least
say what's wrong there, to give a hint at what would need fixing to
remove this restriction) and ...

> +#elif defined (__arm__) || defined(__aarch64__)
> +    16 << 12;
> +#endif
> +
> +static void run_tests(void)
> +{
> +    xen_pfn_t physmap[] = { 0 };
> +    uint64_t size_bytes, old_size_bytes;
> +    int rc;
> +
> +    printf("Test default p2m mempool size\n");
> +
> +    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
> +    if ( rc )
> +        return fail("  Fail: get p2m mempool size: %d - %s\n",
> +                    errno, strerror(errno));
> +
> +    printf("P2M pool size %"PRIu64" bytes (%"PRIu64"kB, %"PRIu64"MB)\n",
> +           size_bytes, size_bytes >> 10, size_bytes >> 20);
> +
> +
> +    /*
> +     * Check that the domain has the expected default allocation size.  This
> +     * will fail if the logic in Xen is altered without an equivelent
> +     * adjustment here.
> +     */
> +    if ( size_bytes != default_p2m_size_bytes )
> +        return fail("  Fail: size %"PRIu64" != expected size %"PRIu64"\n",
> +                    size_bytes, default_p2m_size_bytes);
> +
> +
> +    printf("Test that allocate doesn't alter pool size\n");
> +
> +    /*
> +     * Populate the domain with some RAM.  This will cause more of the p2m
> +     * pool to be used.
> +     */
> +    old_size_bytes = size_bytes;
> +
> +    rc = xc_domain_setmaxmem(xch, domid, -1);
> +    if ( rc )
> +        return fail("  Fail: setmaxmem: : %d - %s\n",
> +                    errno, strerror(errno));
> +
> +    rc = xc_domain_populate_physmap_exact(xch, domid, 1, 0, 0, physmap);
> +    if ( rc )
> +        return fail("  Fail: populate physmap: %d - %s\n",
> +                    errno, strerror(errno));
> +
> +    /*
> +     * Re-get the p2m size.  Should not have changed as a consequence of
> +     * populate physmap.
> +     */
> +    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
> +    if ( rc )
> +        return fail("  Fail: get p2m mempool size: %d - %s\n",
> +                    errno, strerror(errno));
> +
> +    if ( old_size_bytes != size_bytes )
> +        return fail("  Fail: p2m mempool size changed %"PRIu64" => %"PRIu64"\n",
> +                    old_size_bytes, size_bytes);
> +
> +
> +
> +    printf("Test bad set size\n");
> +
> +    /*
> +     * Check that setting a non-page size results in failure.
> +     */
> +    rc = xc_set_p2m_mempool_size(xch, domid, size_bytes + 1);
> +    if ( rc != -1 || errno != EINVAL )
> +        return fail("  Fail: Bad set size: expected -1/EINVAL, got %d/%d - %s\n",
> +                    rc, errno, strerror(errno));
> +
> +
> +    printf("Test very large set size\n");
> +
> +    /*
> +     * Check that setting a large P2M size succeeds.  This is expecting to
> +     * trigger continuations.
> +     */
> +    rc = xc_set_p2m_mempool_size(xch, domid, 64 << 20);
> +    if ( rc )
> +        return fail("  Fail: Set size 64MB: %d - %s\n",
> +                    errno, strerror(errno));
> +
> +
> +    /*
> +     * Check that the reported size matches what set consumed.
> +     */
> +    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
> +    if ( rc )
> +        return fail("  Fail: get p2m mempool size: %d - %s\n",
> +                    errno, strerror(errno));
> +
> +    if ( size_bytes != 64 << 20 )
> +        return fail("  Fail: expected mempool size %u, got %"PRIu64"\n",
> +                    64 << 20, size_bytes);
> +}
> +
> +int main(int argc, char **argv)
> +{
> +    int rc;
> +
> +    printf("P2M Shadow memory pool tests\n");

... the question of why "Shadow" here.

Jan

On 26/10/2022 15:24, Jan Beulich wrote:
> On 26.10.2022 12:20, Andrew Cooper wrote:
>> --- /dev/null
>> +++ b/tools/tests/p2m-pool/Makefile
>> @@ -0,0 +1,42 @@
>> +XEN_ROOT = $(CURDIR)/../../..
>> +include $(XEN_ROOT)/tools/Rules.mk
>> +
>> +TARGET := test-p2m-pool
>> +
>> +.PHONY: all
>> +all: $(TARGET)
>> +
>> +.PHONY: clean
>> +clean:
>> +	$(RM) -- *.o $(TARGET) $(DEPS_RM)
>> +
>> +.PHONY: distclean
>> +distclean: clean
>> +	$(RM) -- *~
>> +
>> +.PHONY: install
>> +install: all
>> +	$(INSTALL_DIR) $(DESTDIR)$(LIBEXEC_BIN)
>> +	$(INSTALL_PROG) $(TARGET) $(DESTDIR)$(LIBEXEC_BIN)
>> +
>> +.PHONY: uninstall
>> +uninstall:
>> +	$(RM) -- $(DESTDIR)$(LIBEXEC_BIN)/$(TARGET)
>> +
>> +CFLAGS += $(CFLAGS_xeninclude)
>> +CFLAGS += $(CFLAGS_libxenctrl)
>> +CFLAGS += $(CFLAGS_libxenforeginmemory)
> Typo here or typo also elsewhere: CFLAGS_libxenforeignmemory? I
> have to admit that I can't really spot where these variables are
> populated. The place in Rules.mk that I could spot uses
>
>  CFLAGS_libxen$(1) = $$(CFLAGS_xeninclude)
>
> i.e. the expansion doesn't really depend on the library.

Hmm.  It was copy&paste from test-resource and I forgot to trim
foreignmemory, but I guess I'll need to go and fix the typo everywhere.

>
> Apart from this looks okay to me, maybe apart from ...
>
>> --- /dev/null
>> +++ b/tools/tests/p2m-pool/test-p2m-pool.c
>> @@ -0,0 +1,181 @@
>> +#include <err.h>
>> +#include <errno.h>
>> +#include <inttypes.h>
>> +#include <stdio.h>
>> +#include <string.h>
>> +#include <sys/mman.h>
>> +
>> +#include <xenctrl.h>
>> +#include <xenforeignmemory.h>
>> +#include <xengnttab.h>
>> +#include <xen-tools/libs.h>
>> +
>> +static unsigned int nr_failures;
>> +#define fail(fmt, ...)                          \
>> +({                                              \
>> +    nr_failures++;                              \
>> +    (void)printf(fmt, ##__VA_ARGS__);           \
>> +})
>> +
>> +static xc_interface *xch;
>> +static uint32_t domid;
>> +
>> +static struct xen_domctl_createdomain create = {
>> +    .flags = XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap,
>> +    .max_vcpus = 1,
>> +    .max_grant_frames = 1,
>> +    .grant_opts = XEN_DOMCTL_GRANT_version(1),
>> +
>> +    .arch = {
>> +#if defined(__x86_64__) || defined(__i386__)
>> +        .emulation_flags = XEN_X86_EMU_LAPIC,
>> +#endif
>> +    },
>> +};
>> +
>> +static uint64_t default_p2m_size_bytes =
>> +#if defined(__x86_64__) || defined(__i386__)
>> +    256 << 12; /* Only x86 HAP for now.  x86 Shadow broken. */
> ... this shadow related comment (the commit message could at least
> say what's wrong there, to give a hint at what would need fixing to
> remove this restriction) and ...

That was in reference to the PV issue.  Will follow it up on patch 1
where there's more context.

>
>> +#elif defined (__arm__) || defined(__aarch64__)
>> +    16 << 12;
>> +#endif
>> +
>> +static void run_tests(void)
>> +{
>> +    xen_pfn_t physmap[] = { 0 };
>> +    uint64_t size_bytes, old_size_bytes;
>> +    int rc;
>> +
>> +    printf("Test default p2m mempool size\n");
>> +
>> +    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
>> +    if ( rc )
>> +        return fail("  Fail: get p2m mempool size: %d - %s\n",
>> +                    errno, strerror(errno));
>> +
>> +    printf("P2M pool size %"PRIu64" bytes (%"PRIu64"kB, %"PRIu64"MB)\n",
>> +           size_bytes, size_bytes >> 10, size_bytes >> 20);
>> +
>> +
>> +    /*
>> +     * Check that the domain has the expected default allocation size.  This
>> +     * will fail if the logic in Xen is altered without an equivelent
>> +     * adjustment here.
>> +     */
>> +    if ( size_bytes != default_p2m_size_bytes )
>> +        return fail("  Fail: size %"PRIu64" != expected size %"PRIu64"\n",
>> +                    size_bytes, default_p2m_size_bytes);
>> +
>> +
>> +    printf("Test that allocate doesn't alter pool size\n");
>> +
>> +    /*
>> +     * Populate the domain with some RAM.  This will cause more of the p2m
>> +     * pool to be used.
>> +     */
>> +    old_size_bytes = size_bytes;
>> +
>> +    rc = xc_domain_setmaxmem(xch, domid, -1);
>> +    if ( rc )
>> +        return fail("  Fail: setmaxmem: : %d - %s\n",
>> +                    errno, strerror(errno));
>> +
>> +    rc = xc_domain_populate_physmap_exact(xch, domid, 1, 0, 0, physmap);
>> +    if ( rc )
>> +        return fail("  Fail: populate physmap: %d - %s\n",
>> +                    errno, strerror(errno));
>> +
>> +    /*
>> +     * Re-get the p2m size.  Should not have changed as a consequence of
>> +     * populate physmap.
>> +     */
>> +    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
>> +    if ( rc )
>> +        return fail("  Fail: get p2m mempool size: %d - %s\n",
>> +                    errno, strerror(errno));
>> +
>> +    if ( old_size_bytes != size_bytes )
>> +        return fail("  Fail: p2m mempool size changed %"PRIu64" => %"PRIu64"\n",
>> +                    old_size_bytes, size_bytes);
>> +
>> +
>> +
>> +    printf("Test bad set size\n");
>> +
>> +    /*
>> +     * Check that setting a non-page size results in failure.
>> +     */
>> +    rc = xc_set_p2m_mempool_size(xch, domid, size_bytes + 1);
>> +    if ( rc != -1 || errno != EINVAL )
>> +        return fail("  Fail: Bad set size: expected -1/EINVAL, got %d/%d - %s\n",
>> +                    rc, errno, strerror(errno));
>> +
>> +
>> +    printf("Test very large set size\n");
>> +
>> +    /*
>> +     * Check that setting a large P2M size succeeds.  This is expecting to
>> +     * trigger continuations.
>> +     */
>> +    rc = xc_set_p2m_mempool_size(xch, domid, 64 << 20);
>> +    if ( rc )
>> +        return fail("  Fail: Set size 64MB: %d - %s\n",
>> +                    errno, strerror(errno));
>> +
>> +
>> +    /*
>> +     * Check that the reported size matches what set consumed.
>> +     */
>> +    rc = xc_get_p2m_mempool_size(xch, domid, &size_bytes);
>> +    if ( rc )
>> +        return fail("  Fail: get p2m mempool size: %d - %s\n",
>> +                    errno, strerror(errno));
>> +
>> +    if ( size_bytes != 64 << 20 )
>> +        return fail("  Fail: expected mempool size %u, got %"PRIu64"\n",
>> +                    64 << 20, size_bytes);
>> +}
>> +
>> +int main(int argc, char **argv)
>> +{
>> +    int rc;
>> +
>> +    printf("P2M Shadow memory pool tests\n");
> ... the question of why "Shadow" here.

Hmm, stale, but even the name of this test (p2m-pool) is subject to a
resolution of the naming question on patch 1.

~Andrew