Re: [kvm-unit-tests PATCH 7/8] s390x: snippets: Add PV support

Claudio Imbrenda
2021-11-23T11:41:55Z

On Tue, 23 Nov 2021 10:39:55 +0000
Janosch Frank <frankja@linux.ibm.com> wrote:

> To create a pv-snippet we need to generate an se-header. This can be
> done using a currently not released tool. This tool creates a
> se-header similar to `genprotimg` with the difference that the image
> itself will not be encrypted.
>
> The image for which we want to create a header must be a binary and
> padded to 4k. Therefore, we convert the compiled snippet to a binary,
> padd it to 4k, generate the header and convert it back to s390-64bit
> elf.
>
> The name of the tool can be specified using the config argument
> `--gen-se-header=`. The pv-snipptes will only be built when this
> option is specified. Furthermore, the Hostkey-Document must be
> specified. If not the build will be skipped.
>
> The host-snippet relation can be specified using the `pv-snippets`
> variable in s390x/Makefile, similar to the non-pv-snippets in
> 2f6fdb4a (s390x: snippets: Add snippet compilation, 2021-06-22)
>
> Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

but see a comment below

> ---
> .gitignore | 2 ++
> configure | 8 ++++++
> lib/s390x/snippet.h | 7 +++++
> s390x/Makefile | 67 +++++++++++++++++++++++++++++++++++++--------
> 4 files changed, 73 insertions(+), 11 deletions(-)
>
> diff --git a/.gitignore b/.gitignore
> index 3d5be622..28a197bf 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -25,3 +25,5 @@ cscope.*
> /api/dirty-log-perf
> /s390x/*.bin
> /s390x/snippets/*/*.gbin
> +/s390x/snippets/*/*.hdr
> +/s390x/snippets/*/*.*obj
> \ No newline at end of file
> diff --git a/configure b/configure
> index 1d4d855e..9210912f 100755
> --- a/configure
> +++ b/configure
> @@ -26,6 +26,7 @@ target=
> errata_force=0
> erratatxt="$srcdir/errata.txt"
> host_key_document=
> +gen_se_header=
> page_size=
> earlycon=
>
> @@ -54,6 +55,9 @@ usage() {
> --host-key-document=HOST_KEY_DOCUMENT
> Specify the machine-specific host-key document for creating
> a PVM image with 'genprotimg' (s390x only)
> + --gen-se-header=GEN_SE_HEADER
> + Provide an executable to generate a PV header
> + requires --host-key-document. (s390x-snippets only)
> --page-size=PAGE_SIZE
> Specify the page size (translation granule) (4k, 16k or
> 64k, default is 64k, arm64 only)
> @@ -127,6 +131,9 @@ while [[ "$1" = -* ]]; do
> --host-key-document)
> host_key_document="$arg"
> ;;
> + --gen-se-header)
> + gen_se_header="$arg"
> + ;;
> --page-size)
> page_size="$arg"
> ;;
> @@ -341,6 +348,7 @@ U32_LONG_FMT=$u32_long
> WA_DIVIDE=$wa_divide
> GENPROTIMG=${GENPROTIMG-genprotimg}
> HOST_KEY_DOCUMENT=$host_key_document
> +GEN_SE_HEADER=$gen_se_header
> EOF
> if [ "$arch" = "arm" ] || [ "$arch" = "arm64" ]; then
> echo "TARGET=$target" >> config.mak
> diff --git a/lib/s390x/snippet.h b/lib/s390x/snippet.h
> index 8e4765f8..6b77a8a9 100644
> --- a/lib/s390x/snippet.h
> +++ b/lib/s390x/snippet.h
> @@ -14,10 +14,17 @@
> _binary_s390x_snippets_##type##_##file##_gbin_start
> #define SNIPPET_NAME_END(type, file) \
> _binary_s390x_snippets_##type##_##file##_gbin_end
> +#define SNIPPET_HDR_START(type, file) \
> + _binary_s390x_snippets_##type##_##file##_hdr_start
> +#define SNIPPET_HDR_END(type, file) \
> + _binary_s390x_snippets_##type##_##file##_hdr_end
> +
>
> /* Returns the length of the snippet */
> #define SNIPPET_LEN(type, file) \
> ((uintptr_t)SNIPPET_NAME_END(type, file) - (uintptr_t)SNIPPET_NAME_START(type, file))
> +#define SNIPPET_HDR_LEN(type, file) \
> + ((uintptr_t)SNIPPET_HDR_END(type, file) - (uintptr_t)SNIPPET_HDR_START(type, file))
>
> /*
> * C snippet instructions start at 0x4000 due to the prefix and the
> diff --git a/s390x/Makefile b/s390x/Makefile
> index f95f2e61..55e6d962 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -26,12 +26,20 @@ tests += $(TEST_DIR)/edat.elf
> tests += $(TEST_DIR)/mvpg-sie.elf
> tests += $(TEST_DIR)/spec_ex-sie.elf
>
> +ifneq ($(HOST_KEY_DOCUMENT),)
> +ifneq ($(GEN_SE_HEADER),)
> +tests += $(pv-tests)
> +endif
> +endif
> +
> tests_binary = $(patsubst %.elf,%.bin,$(tests))
> ifneq ($(HOST_KEY_DOCUMENT),)
> tests_pv_binary = $(patsubst %.bin,%.pv.bin,$(tests_binary))
> else
> tests_pv_binary =
> +GEN_SE_HEADER =
> endif
> +snippets-obj = $(patsubst %.gbin,%.gobj,$(snippets))
>
> all: directories test_cases test_cases_binary test_cases_pv
>
> @@ -82,26 +90,59 @@ asmlib = $(TEST_DIR)/cstart64.o $(TEST_DIR)/cpu.o
> FLATLIBS = $(libcflat)
>
> SNIPPET_DIR = $(TEST_DIR)/snippets
> -snippet_asmlib = $(SNIPPET_DIR)/c/cstart.o lib/auxinfo.o
> +snippet_asmlib = $(SNIPPET_DIR)/c/cstart.o
> +snippet_lib = $(snippet_asmlib) lib/auxinfo.o
>
> # perquisites (=guests) for the snippet hosts.
> # $(TEST_DIR)/<snippet-host>.elf: snippets = $(SNIPPET_DIR)/<c/asm>/<snippet>.gbin
> $(TEST_DIR)/mvpg-sie.elf: snippets = $(SNIPPET_DIR)/c/mvpg-snippet.gbin
> $(TEST_DIR)/spec_ex-sie.elf: snippets = $(SNIPPET_DIR)/c/spec_ex.gbin
>
> -$(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o $(FLATLIBS)
> - $(OBJCOPY) -O binary $(patsubst %.gbin,%.o,$@) $@
> - $(OBJCOPY) -I binary -O elf64-s390 -B "s390:64-bit" $@ $@
> +ifneq ($(GEN_SE_HEADER),)
> +snippets += $(pv-snippets)
> +tests += $(pv-tests)
> +snippet-hdr-obj = $(patsubst %.gbin,%.hdr.obj,$(pv-snippets))
> +else
> +snippet-hdr-obj =
> +endif
> +
> +# the asm/c snippets %.o have additional generated files as dependencies
> +$(SNIPPET_DIR)/asm/%.o: $(SNIPPET_DIR)/asm/%.S $(asm-offsets)
> + $(CC) $(CFLAGS) -c -nostdlib -o $@ $<
> +
> +$(SNIPPET_DIR)/c/%.o: $(SNIPPET_DIR)/c/%.c $(asm-offsets)
> + $(CC) $(CFLAGS) -c -nostdlib -o $@ $<
> +
> +$(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o
> + $(OBJCOPY) -O binary -j ".rodata" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $(patsubst %.gbin,%.o,$@) $@
> + truncate -s '%4096' $@
> +
> +$(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
> + $(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/snippets/c/flat.lds $(patsubst %.gbin,%.o,$@) $(snippet_lib) $(FLATLIBS)
> + $(OBJCOPY) -O binary -j ".rodata" -j ".lowcore" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $@ $@
> + truncate -s '%4096' $@
> +
> +$(SNIPPET_DIR)/asm/%.hdr: $(SNIPPET_DIR)/asm/%.gbin $(HOST_KEY_DOCUMENT)
> + $(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x4000,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
> +
> +$(SNIPPET_DIR)/c/%.hdr: $(SNIPPET_DIR)/c/%.gbin $(HOST_KEY_DOCUMENT)
> + $(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@

are they supposed to have different addresses?
the C files start at 0x4000, while the asm ones at 0

> +
> +.SECONDARY:
> +%.gobj: %.gbin
> + $(OBJCOPY) -I binary -O elf64-s390 -B "s390:64-bit" $< $@
> +
> +.SECONDARY:
> +%.hdr.obj: %.hdr
> + $(OBJCOPY) -I binary -O elf64-s390 -B "s390:64-bit" $< $@
>
> -$(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_asmlib) $(FLATLIBS)
> - $(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/snippets/c/flat.lds $(patsubst %.gbin,%.o,$@) $(snippet_asmlib) $(FLATLIBS)
> - $(OBJCOPY) -O binary $@ $@
> - $(OBJCOPY) -I binary -O elf64-s390 -B "s390:64-bit" $@ $@
>
> .SECONDEXPANSION:
> -%.elf: $$(snippets) %.o $(FLATLIBS) $(SRCDIR)/s390x/flat.lds $(asmlib)
> +%.elf: $(FLATLIBS) $(asmlib) $(SRCDIR)/s390x/flat.lds $$(snippets-obj) $$(snippet-hdr-obj) %.o
> $(CC) $(CFLAGS) -c -o $(@:.elf=.aux.o) $(SRCDIR)/lib/auxinfo.c -DPROGNAME=\"$@\"
> - $(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/flat.lds $(filter %.o, $^) $(FLATLIBS) $(snippets) $(@:.elf=.aux.o)
> + @$(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/flat.lds \
> + $(filter %.o, $^) $(FLATLIBS) $(snippets-obj) $(snippet-hdr-obj) $(@:.elf=.aux.o) || \
> + { echo "Failure probably caused by missing definition of gen-se-header executable"; exit 1; }
> $(RM) $(@:.elf=.aux.o)
> @chmod a-x $@
>
> @@ -114,8 +155,12 @@ $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_asmlib) $(FLATLIBS)
> %.pv.bin: %.bin $(HOST_KEY_DOCUMENT)
> $(GENPROTIMG) --host-key-document $(HOST_KEY_DOCUMENT) --no-verify --image $< -o $@
>
> +$(snippet_asmlib): $$(patsubst %.o,%.S,$$@) $(asm-offsets)
> + $(CC) $(CFLAGS) -c -nostdlib -o $@ $<
> +
> +
> arch_clean: asm_offsets_clean
> - $(RM) $(TEST_DIR)/*.{o,elf,bin} $(TEST_DIR)/.*.d $(SNIPPET_DIR)/c/*.{o,gbin} $(SNIPPET_DIR)/c/.*.d lib/s390x/.*.d
> + $(RM) $(TEST_DIR)/*.{o,elf,bin} $(SNIPPET_DIR)/*/*.{o,elf,*bin,*obj,hdr} $(SNIPPET_DIR)/asm/.*.d $(TEST_DIR)/.*.d lib/s390x/.*.d
>
> generated-files = $(asm-offsets)
> $(tests:.elf=.o) $(asmlib) $(cflatobjs): $(generated-files)