On 2026-09-25 01:30 AM, Samiullah Khawaja wrote: > Libvfio depends on an external dependency libuuid for parsing vf_tokens. > Building it in cross compilation environments gives the following error, > > ld: cannot find -luuid: No such file or directory
It also complicates compiling with glibc alternatives like musl. See https://lore.kernel.org/kvm/[email protected]/ Please mention that as well for historical context. > As it is only used for parsing vf_tokens, remove the dependency by open > coding the parser where it is required. > > Tested by running vfio_pci_sriov_uapi_test selftest. > > Assisted-by: Claude:claude-opus-5 > Signed-off-by: Samiullah Khawaja <[email protected]> > --- > tools/testing/selftests/vfio/lib/libvfio.mk | 2 - > .../selftests/vfio/lib/vfio_pci_device.c | 57 ++++++++++++++++--- > 2 files changed, 50 insertions(+), 9 deletions(-) > > diff --git a/tools/testing/selftests/vfio/lib/libvfio.mk > b/tools/testing/selftests/vfio/lib/libvfio.mk > index bcfa74ae040e..7d6916ca3940 100644 > --- a/tools/testing/selftests/vfio/lib/libvfio.mk > +++ b/tools/testing/selftests/vfio/lib/libvfio.mk > @@ -29,8 +29,6 @@ $(LIBVFIO_O_DIRS): > > CFLAGS += -I$(LIBVFIO_SRCDIR)/include > > -LDLIBS += -luuid > - > $(LIBVFIO_O): $(LIBVFIO_OUTPUT)/%.o : $(LIBVFIO_SRCDIR)/%.c | > $(LIBVFIO_O_DIRS) > $(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@ > > diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_device.c > b/tools/testing/selftests/vfio/lib/vfio_pci_device.c > index 4063a0e2b3df..774d1e90ec0e 100644 > --- a/tools/testing/selftests/vfio/lib/vfio_pci_device.c > +++ b/tools/testing/selftests/vfio/lib/vfio_pci_device.c > @@ -23,11 +23,54 @@ > #include <linux/types.h> > #include <linux/vfio.h> > > -#include <uuid/uuid.h> > - > #include "kselftest.h" > #include <libvfio.h> > > +/* > + * Minimal replacement for libuuid's uuid_parse(). libuuid is part of > + * util-linux and is routinely absent from cross-compilation sysroots, which > + * makes the vfio selftests unbuildable for non-native architectures. The > only > + * thing needed from it is parsing a VF token, so open-code that instead. > + */ > +#define VFIO_UUID_LEN 16 > +#define VFIO_UUID_STR_LEN 36 > + > +static int vfio_uuid_hexval(char c) > +{ > + if (c >= '0' && c <= '9') > + return c - '0'; > + if (c >= 'a' && c <= 'f') > + return c - 'a' + 10; > + if (c >= 'A' && c <= 'F') > + return c - 'A' + 10; > + return -1; > +} > + > +static int vfio_uuid_parse(const char *in, unsigned char uu[VFIO_UUID_LEN]) Do we need the vfio_/VFIO_ prefixes now that we aren't linking libuuid? > +{ > + const char *p = in; > + int i, hi, lo; > + > + if (strlen(in) != VFIO_UUID_STR_LEN) > + return -1; > + > + for (i = 0; i < VFIO_UUID_LEN; i++) { > + if (i == 4 || i == 6 || i == 8 || i == 10) { > + if (*p++ != '-') > + return -1; > + } > + > + hi = vfio_uuid_hexval(*p++); > + lo = vfio_uuid_hexval(*p++); > + if (hi < 0 || lo < 0) > + return -1; > + > + uu[i] = (hi << 4) | lo; > + } > + > + return 0; > +} Please move the uuid changes into lib/uuid.c and lib/include/libvfio/uuid.h in case we want to use them elsewhere in the future. > + > static void vfio_pci_irq_set(struct vfio_pci_device *device, > u32 index, u32 vector, u32 count, int *fds) > { > @@ -167,13 +210,13 @@ static void vfio_device_feature_set(int fd, u16 > feature, void *data, size_t data > > void vfio_device_set_vf_token(int fd, const char *vf_token) > { > - uuid_t token_uuid = {0}; > + unsigned char token_uuid[VFIO_UUID_LEN] = {0}; Any reason not to define a uuid_t? > > VFIO_ASSERT_NOT_NULL(vf_token, "vf_token is NULL"); > - VFIO_ASSERT_EQ(uuid_parse(vf_token, token_uuid), 0); > + VFIO_ASSERT_EQ(vfio_uuid_parse(vf_token, token_uuid), 0); > > vfio_device_feature_set(fd, VFIO_DEVICE_FEATURE_PCI_VF_TOKEN, > - token_uuid, sizeof(uuid_t)); > + token_uuid, sizeof(token_uuid)); > } > > static void vfio_pci_region_get(struct vfio_pci_device *device, int index, > @@ -415,10 +458,10 @@ int __vfio_device_bind_iommufd(int device_fd, int > iommufd, const char *vf_token) > .argsz = sizeof(args), > .iommufd = iommufd, > }; > - uuid_t token_uuid; > + unsigned char token_uuid[VFIO_UUID_LEN]; > > if (vf_token) { > - VFIO_ASSERT_EQ(uuid_parse(vf_token, token_uuid), 0); > + VFIO_ASSERT_EQ(vfio_uuid_parse(vf_token, token_uuid), 0); > args.flags |= VFIO_DEVICE_BIND_FLAG_TOKEN; > args.token_uuid_ptr = (u64)token_uuid; > } > > base-commit: 3d7783543c2646af69ad65825e810060494bea21 > -- > 2.56.0.rc1.315.gc6ed9934b7-goog >
