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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: D147FA0006 X-Stat-Signature: rhiczqk8rrs11ruxbozou8a5ktderqdh X-Rspam-User: X-HE-Tag: 1769446264-974659 X-HE-Meta: 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 OQAcVwVG 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Patrick Roy =0A= =0A= If guest memory is backed using a VMA that does not allow GUP (e.g. a=0A= userspace mapping of guest_memfd when the fd was allocated using=0A= GUEST_MEMFD_FLAG_NO_DIRECT_MAP), then directly loading the test ELF=0A= binary into it via read(2) potentially does not work. To nevertheless=0A= support loading binaries in this cases, do the read(2) syscall using a=0A= bounce buffer, and then memcpy from the bounce buffer into guest memory.=0A= =0A= Signed-off-by: Patrick Roy =0A= Signed-off-by: Nikita Kalyazin =0A= ---=0A= .../testing/selftests/kvm/include/test_util.h | 1 +=0A= tools/testing/selftests/kvm/lib/elf.c | 8 +++----=0A= tools/testing/selftests/kvm/lib/io.c | 23 +++++++++++++++++++=0A= 3 files changed, 28 insertions(+), 4 deletions(-)=0A= =0A= diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testin= g/selftests/kvm/include/test_util.h=0A= index b4872ba8ed12..8140e59b59e5 100644=0A= --- a/tools/testing/selftests/kvm/include/test_util.h=0A= +++ b/tools/testing/selftests/kvm/include/test_util.h=0A= @@ -48,6 +48,7 @@ do { \=0A= =0A= ssize_t test_write(int fd, const void *buf, size_t count);=0A= ssize_t test_read(int fd, void *buf, size_t count);=0A= +ssize_t test_read_bounce(int fd, void *buf, size_t count);=0A= int test_seq_read(const char *path, char **bufp, size_t *sizep);=0A= =0A= void __printf(5, 6) test_assert(bool exp, const char *exp_str,=0A= diff --git a/tools/testing/selftests/kvm/lib/elf.c b/tools/testing/selftest= s/kvm/lib/elf.c=0A= index f34d926d9735..e829fbe0a11e 100644=0A= --- a/tools/testing/selftests/kvm/lib/elf.c=0A= +++ b/tools/testing/selftests/kvm/lib/elf.c=0A= @@ -31,7 +31,7 @@ static void elfhdr_get(const char *filename, Elf64_Ehdr *= hdrp)=0A= * the real size of the ELF header.=0A= */=0A= unsigned char ident[EI_NIDENT];=0A= - test_read(fd, ident, sizeof(ident));=0A= + test_read_bounce(fd, ident, sizeof(ident));=0A= TEST_ASSERT((ident[EI_MAG0] =3D=3D ELFMAG0) && (ident[EI_MAG1] =3D=3D ELF= MAG1)=0A= && (ident[EI_MAG2] =3D=3D ELFMAG2) && (ident[EI_MAG3] =3D=3D ELFMAG3),= =0A= "ELF MAGIC Mismatch,\n"=0A= @@ -79,7 +79,7 @@ static void elfhdr_get(const char *filename, Elf64_Ehdr *= hdrp)=0A= offset_rv =3D lseek(fd, 0, SEEK_SET);=0A= TEST_ASSERT(offset_rv =3D=3D 0, "Seek to ELF header failed,\n"=0A= " rv: %zi expected: %i", offset_rv, 0);=0A= - test_read(fd, hdrp, sizeof(*hdrp));=0A= + test_read_bounce(fd, hdrp, sizeof(*hdrp));=0A= TEST_ASSERT(hdrp->e_phentsize =3D=3D sizeof(Elf64_Phdr),=0A= "Unexpected physical header size,\n"=0A= " hdrp->e_phentsize: %x\n"=0A= @@ -146,7 +146,7 @@ void kvm_vm_elf_load(struct kvm_vm *vm, const char *fil= ename)=0A= =0A= /* Read in the program header. */=0A= Elf64_Phdr phdr;=0A= - test_read(fd, &phdr, sizeof(phdr));=0A= + test_read_bounce(fd, &phdr, sizeof(phdr));=0A= =0A= /* Skip if this header doesn't describe a loadable segment. */=0A= if (phdr.p_type !=3D PT_LOAD)=0A= @@ -187,7 +187,7 @@ void kvm_vm_elf_load(struct kvm_vm *vm, const char *fil= ename)=0A= " expected: 0x%jx",=0A= n1, errno, (intmax_t) offset_rv,=0A= (intmax_t) phdr.p_offset);=0A= - test_read(fd, addr_gva2hva(vm, phdr.p_vaddr),=0A= + test_read_bounce(fd, addr_gva2hva(vm, phdr.p_vaddr),=0A= phdr.p_filesz);=0A= }=0A= }=0A= diff --git a/tools/testing/selftests/kvm/lib/io.c b/tools/testing/selftests= /kvm/lib/io.c=0A= index fedb2a741f0b..74419becc8bc 100644=0A= --- a/tools/testing/selftests/kvm/lib/io.c=0A= +++ b/tools/testing/selftests/kvm/lib/io.c=0A= @@ -155,3 +155,26 @@ ssize_t test_read(int fd, void *buf, size_t count)=0A= =0A= return num_read;=0A= }=0A= +=0A= +/* Test read via intermediary buffer=0A= + *=0A= + * Same as test_read, except read(2)s happen into a bounce buffer that is = memcpy'd=0A= + * to buf. For use with buffers that cannot be GUP'd (e.g. guest_memfd VMA= s if=0A= + * guest_memfd was created with GUEST_MEMFD_FLAG_NO_DIRECT_MAP).=0A= + */=0A= +ssize_t test_read_bounce(int fd, void *buf, size_t count)=0A= +{=0A= + void *bounce_buffer;=0A= + ssize_t num_read;=0A= +=0A= + TEST_ASSERT(count >=3D 0, "Unexpected count, count: %li", count);=0A= +=0A= + bounce_buffer =3D malloc(count);=0A= + TEST_ASSERT(bounce_buffer !=3D NULL, "Failed to allocate bounce buffer");= =0A= +=0A= + num_read =3D test_read(fd, bounce_buffer, count);=0A= + memcpy(buf, bounce_buffer, num_read);=0A= + free(bounce_buffer);=0A= +=0A= + return num_read;=0A= +}=0A= -- =0A= 2.50.1=0A= =0A=