Re: [kvm-unit-tests PATCH v8 6/6] s390x: SCLP unit test

David Hildenbrand
2020-01-22T10:10:35Z

On 20.01.20 19:42, Claudio Imbrenda wrote:
> SCLP unit test. Testing the following:
>
> * Correctly ignoring instruction bits that should be ignored
> * Privileged instruction check
> * Check for addressing exceptions
> * Specification exceptions:
> - SCCB size less than 8
> - SCCB unaligned
> - SCCB overlaps prefix or lowcore
> - SCCB address higher than 2GB
> * Return codes for
> - Invalid command
> - SCCB too short (but at least 8)
> - SCCB page boundary violation
>
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> Acked-by: Janosch Frank <frankja@linux.ibm.com>
> ---
> s390x/Makefile | 1 +
> s390x/sclp.c | 474 ++++++++++++++++++++++++++++++++++++++++++++
> s390x/unittests.cfg | 8 +
> 3 files changed, 483 insertions(+)
> create mode 100644 s390x/sclp.c
>
> diff --git a/s390x/Makefile b/s390x/Makefile
> index 3744372..ddb4b48 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -16,6 +16,7 @@ tests += $(TEST_DIR)/diag288.elf
> tests += $(TEST_DIR)/stsi.elf
> tests += $(TEST_DIR)/skrf.elf
> tests += $(TEST_DIR)/smp.elf
> +tests += $(TEST_DIR)/sclp.elf
> tests_binary = $(patsubst %.elf,%.bin,$(tests))
>
> all: directories test_cases test_cases_binary
> diff --git a/s390x/sclp.c b/s390x/sclp.c
> new file mode 100644
> index 0000000..215347e
> --- /dev/null
> +++ b/s390x/sclp.c
> @@ -0,0 +1,474 @@
> +/*
> + * Service Call tests
> + *
> + * Copyright (c) 2019 IBM Corp
> + *
> + * Authors:
> + * Claudio Imbrenda <imbrenda@linux.ibm.com>
> + *
> + * This code is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License version 2.
> + */
> +
> +#include <libcflat.h>
> +#include <asm/page.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/interrupt.h>
> +#include <sclp.h>
> +
> +#define PGM_NONE 1
> +#define PGM_BIT_SPEC (1ULL << PGM_INT_CODE_SPECIFICATION)
> +#define PGM_BIT_ADDR (1ULL << PGM_INT_CODE_ADDRESSING)
> +#define PGM_BIT_PRIV (1ULL << PGM_INT_CODE_PRIVILEGED_OPERATION)
> +#define MKPTR(x) ((void *)(uint64_t)(x))
> +
> +#define LC_SIZE (2 * PAGE_SIZE)
> +
> +static uint8_t pagebuf[LC_SIZE] __attribute__((aligned(LC_SIZE))); /* scratch pages used for some tests */
> +static uint8_t prefix_buf[LC_SIZE] __attribute__((aligned(LC_SIZE))); /* temporary lowcore for test_sccb_prefix */
> +static uint8_t sccb_template[PAGE_SIZE]; /* SCCB template to be used */
> +static uint32_t valid_code; /* valid command code for READ SCP INFO */
> +static struct lowcore *lc;
> +
> +/**
> + * Perform one service call, handling exceptions and interrupts.
> + */
> +static int sclp_service_call_test(unsigned int command, void *sccb)
> +{
> + int cc;
> +
> + sclp_mark_busy();
> + sclp_setup_int();
> + cc = servc(command, __pa(sccb));
> + if (lc->pgm_int_code) {
> + sclp_handle_ext();
> + return 0;
> + }
> + if (!cc)
> + sclp_wait_busy();
> + return cc;
> +}
> +
> +/**
> + * Perform one test at the given address, optionally using the SCCB template,
> + * checking for the expected program interrupts and return codes.
> + *
> + * The parameter buf_len indicates the number of bytes of the template that
> + * should be copied to the test address, and should be 0 when the test
> + * address is invalid, in which case nothing is copied.
> + *
> + * The template is used to simplify tests where the same buffer content is
> + * used many times in a row, at different addresses.
> + *
> + * Returns true in case of success or false in case of failure
> + */
> +static bool test_one_sccb(uint32_t cmd, uint8_t *addr, uint16_t buf_len, uint64_t exp_pgm, uint16_t exp_rc)
> +{
> + SCCBHeader *h = (SCCBHeader *)addr;
> + int res, pgm;
> +
> + /* Copy the template to the test address if needed */
> + if (buf_len)
> + memcpy(addr, sccb_template, buf_len);
> + if (exp_pgm != PGM_NONE)
> + expect_pgm_int();
> + /* perform the actual call */
> + res = sclp_service_call_test(cmd, h);
> + if (res) {
> + report_info("SCLP not ready (command %#x, address %p, cc %d)", cmd, addr, res);
> + return false;
> + }
> + pgm = clear_pgm_int();
> + /* Check if the program exception was one of the expected ones */
> + if (!((1ULL << pgm) & exp_pgm)) {
> + report_info("First failure at addr %p, buf_len %d, cmd %#x, pgm code %d",
> + addr, buf_len, cmd, pgm);
> + return false;
> + }
> + /* Check if the response code is the one expected */
> + if (exp_rc && exp_rc != h->response_code) {
> + report_info("First failure at addr %p, buf_len %d, cmd %#x, resp code %#x",
> + addr, buf_len, cmd, h->response_code);
> + return false;
> + }
> + return true;
> +}
> +
> +/**
> + * Wrapper for test_one_sccb to be used when the template should not be
> + * copied and the memory address should not be touched.
> + */
> +static bool test_one_ro(uint32_t cmd, uint8_t *addr, uint64_t exp_pgm, uint16_t exp_rc)
> +{
> + return test_one_sccb(cmd, addr, 0, exp_pgm, exp_rc);
> +}
> +
> +/**
> + * Wrapper for test_one_sccb to set up a simple SCCB template.
> + *
> + * The parameter sccb_len indicates the value that will be saved in the SCCB
> + * length field of the SCCB, buf_len indicates the number of bytes of
> + * template that need to be copied to the actual test address. In many cases
> + * it's enough to clear/copy the first 8 bytes of the buffer, while the SCCB
> + * itself can be larger.
> + *
> + * Returns true in case of success or false in case of failure
> + */
> +static bool test_one_simple(uint32_t cmd, uint8_t *addr, uint16_t sccb_len,
> + uint16_t buf_len, uint64_t exp_pgm, uint16_t exp_rc)
> +{
> + memset(sccb_template, 0, sizeof(sccb_template));
> + ((SCCBHeader *)sccb_template)->length = sccb_len;
> + return test_one_sccb(cmd, addr, buf_len, exp_pgm, exp_rc);

Doing a fresh ./configure + make on RHEL7 gives me

[linux1@rhkvm01 kvm-unit-tests]$ make
gcc -std=gnu99 -ffreestanding -I /home/linux1/git/kvm-unit-tests/lib -I /home/linux1/git/kvm-unit-tests/lib/s390x -I lib -O2 -march=zEC12 -fno-delete-null-pointer-checks -g -MMD -MF s390x/.sclp.d -Wall -Wwrite-strings -Wempty-body -Wuninitialized -Wignored-qualifiers -Werror -fomit-frame-pointer -Wno-frame-address -fno-pic -Wclobbered -Wunused-but-set-parameter -Wmissing-parameter-type -Wold-style-declaration -Woverride-init -Wmissing-prototypes -Wstrict-prototypes -c -o s390x/sclp.o s390x/sclp.c
s390x/sclp.c: In function 'test_one_simple':
s390x/sclp.c:121:2: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
((SCCBHeader *)sccb_template)->length = sccb_len;
^
s390x/sclp.c: At top level:
cc1: error: unrecognized command line option "-Wno-frame-address" [-Werror]
cc1: all warnings being treated as errors
make: *** [s390x/sclp.o] Error 1

--
Thanks,

David / dhildenb