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

Janosch Frank <frankja@xxxxxxxxxxxxx> · Fri, 26 Nov 2021 14:28:15 +0100

On 11/23/21 12:22, Claudio Imbrenda wrote:
On Tue, 23 Nov 2021 10:39:55 +0000
Janosch Frank <frankja@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx>

Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>

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

That's a mistake I'll need to fix.


+
+.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)








