On Fri, 17 Mar 2023 12:23:39 +0100 Nina Schoetterl-Glausch <nsg@xxxxxxxxxxxxx> wrote: > Test the instruction address used by targets of an execute instruction. > When the target instruction calculates a relative address, the result is > relative to the target instruction, not the execute instruction. > > Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx> Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> > Signed-off-by: Nina Schoetterl-Glausch <nsg@xxxxxxxxxxxxx> > --- > > > v5 -> v6: > * fix section for exrl targets (thanks Claudio) > * add comments (thanks Claudio) > > v4 -> v5: > * word align the execute-type instruction, preventing a specification > exception if the address calculation is wrong, since LLGFRL requires > word alignment > * change wording of comment > > v3 -> v4: > * fix nits (thanks Janosch) > * pickup R-b (thanks Janosch) > > v2 -> v3: > * add some comments (thanks Janosch) > * add two new tests (drop Nico's R-b) > * push prefix > > v1 -> v2: > * add test to unittests.cfg and .gitlab-ci.yml > * pick up R-b (thanks Nico) > > > See https://patchew.org/QEMU/20230316210751.302423-1-iii@xxxxxxxxxxxxx/ > for TCG fixes. > > > Range-diff against v5: > 1: 57f8f256 ! 1: 3893f723 s390x: Add tests for execute-type instructions > @@ s390x/ex.c (new) > +#include <libcflat.h> > + > +/* > ++ * Accesses to the operand of execute-type instructions are instruction fetches. > ++ * Minimum alignment is two, since the relative offset is specified by number of halfwords. > ++ */ > ++asm ( ".pushsection .text.exrl_targets,\"x\"\n" > ++" .balign 2\n" > ++" .popsection\n" > ++); > ++ > ++/* > + * BRANCH AND SAVE, register register variant. > + * Saves the next instruction address (address from PSW + length of instruction) > + * to the first register. No branch is taken in this test, because 0 is > @@ s390x/ex.c (new) > + uint64_t ret_addr, after_ex; > + > + report_prefix_push("BASR"); > -+ asm volatile ( ".pushsection .rodata\n" > ++ asm volatile ( ".pushsection .text.exrl_targets\n" > + "0: basr %[ret_addr],0\n" > + " .popsection\n" > + > @@ s390x/ex.c (new) > + uint64_t after_target, ret_addr, after_ex, branch_addr; > + > + report_prefix_push("BRAS"); > -+ asm volatile ( ".pushsection .text.ex_bras, \"x\"\n" > ++ asm volatile ( ".pushsection .text.exrl_targets\n" > + "0: bras %[ret_addr],1f\n" > + " nopr %%r7\n" > + "1: larl %[branch_addr],0\n" > @@ s390x/ex.c (new) > + " larl %[after_target],1b\n" > + " larl %[after_ex],3f\n" > + "2: exrl 0,0b\n" > ++/* > ++ * In case the address calculation is correct, we jump by the relative offset 1b-0b from 0b to 1b. > ++ * In case the address calculation is relative to the exrl (i.e. a test failure), > ++ * put a valid instruction at the same relative offset from the exrl, so the test continues in a > ++ * controlled manner. > ++ */ > + "3: larl %[branch_addr],0\n" > + "4:\n" > + > @@ s390x/ex.c (new) > + uint64_t target, addr; > + > + report_prefix_push("LARL"); > -+ asm volatile ( ".pushsection .rodata\n" > ++ asm volatile ( ".pushsection .text.exrl_targets\n" > + "0: larl %[addr],0\n" > + " .popsection\n" > + > @@ s390x/ex.c (new) > + uint64_t target, value; > + > + report_prefix_push("LLGFRL"); > -+ asm volatile ( ".pushsection .rodata\n" > ++ asm volatile ( ".pushsection .text.exrl_targets\n" > + " .balign 4\n" > ++ //operand of llgfrl must be word aligned > + "0: llgfrl %[value],0\n" > + " .popsection\n" > + > @@ s390x/ex.c (new) > + uint32_t program_mask, cc, crl_word; > + > + report_prefix_push("CRL"); > -+ asm volatile ( ".pushsection .rodata\n" > ++ asm volatile ( ".pushsection .text.exrl_targets\n" > + //operand of crl must be word aligned > + " .balign 4\n" > + "0: crl %[crl_word],0\n" > > s390x/Makefile | 1 + > s390x/ex.c | 188 ++++++++++++++++++++++++++++++++++++++++++++ > s390x/unittests.cfg | 3 + > .gitlab-ci.yml | 1 + > 4 files changed, 193 insertions(+) > create mode 100644 s390x/ex.c > > diff --git a/s390x/Makefile b/s390x/Makefile > index 97a61611..6cf8018b 100644 > --- a/s390x/Makefile > +++ b/s390x/Makefile > @@ -39,6 +39,7 @@ tests += $(TEST_DIR)/panic-loop-extint.elf > tests += $(TEST_DIR)/panic-loop-pgm.elf > tests += $(TEST_DIR)/migration-sck.elf > tests += $(TEST_DIR)/exittime.elf > +tests += $(TEST_DIR)/ex.elf > > pv-tests += $(TEST_DIR)/pv-diags.elf > > diff --git a/s390x/ex.c b/s390x/ex.c > new file mode 100644 > index 00000000..dbd8030d > --- /dev/null > +++ b/s390x/ex.c > @@ -0,0 +1,188 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright IBM Corp. 2023 > + * > + * Test EXECUTE (RELATIVE LONG). > + * These instructions execute a target instruction. The target instruction is formed > + * by reading an instruction from memory and optionally modifying some of its bits. > + * The execution of the target instruction is the same as if it was executed > + * normally as part of the instruction sequence, except for the instruction > + * address and the instruction-length code. > + */ > + > +#include <libcflat.h> > + > +/* > + * Accesses to the operand of execute-type instructions are instruction fetches. > + * Minimum alignment is two, since the relative offset is specified by number of halfwords. > + */ > +asm ( ".pushsection .text.exrl_targets,\"x\"\n" > +" .balign 2\n" > +" .popsection\n" > +); > + > +/* > + * BRANCH AND SAVE, register register variant. > + * Saves the next instruction address (address from PSW + length of instruction) > + * to the first register. No branch is taken in this test, because 0 is > + * specified as target. > + * BASR does *not* perform a relative address calculation with an intermediate. > + */ > +static void test_basr(void) > +{ > + uint64_t ret_addr, after_ex; > + > + report_prefix_push("BASR"); > + asm volatile ( ".pushsection .text.exrl_targets\n" > + "0: basr %[ret_addr],0\n" > + " .popsection\n" > + > + " larl %[after_ex],1f\n" > + " exrl 0,0b\n" > + "1:\n" > + : [ret_addr] "=d" (ret_addr), > + [after_ex] "=d" (after_ex) > + ); > + > + report(ret_addr == after_ex, "return address after EX"); > + report_prefix_pop(); > +} > + > +/* > + * BRANCH RELATIVE AND SAVE. > + * According to PoP (Branch-Address Generation), the address calculated relative > + * to the instruction address is relative to BRAS when it is the target of an > + * execute-type instruction, not relative to the execute-type instruction. > + */ > +static void test_bras(void) > +{ > + uint64_t after_target, ret_addr, after_ex, branch_addr; > + > + report_prefix_push("BRAS"); > + asm volatile ( ".pushsection .text.exrl_targets\n" > + "0: bras %[ret_addr],1f\n" > + " nopr %%r7\n" > + "1: larl %[branch_addr],0\n" > + " j 4f\n" > + " .popsection\n" > + > + " larl %[after_target],1b\n" > + " larl %[after_ex],3f\n" > + "2: exrl 0,0b\n" > +/* > + * In case the address calculation is correct, we jump by the relative offset 1b-0b from 0b to 1b. > + * In case the address calculation is relative to the exrl (i.e. a test failure), > + * put a valid instruction at the same relative offset from the exrl, so the test continues in a > + * controlled manner. > + */ > + "3: larl %[branch_addr],0\n" > + "4:\n" > + > + " .if (1b - 0b) != (3b - 2b)\n" > + " .error \"right and wrong target must have same offset\"\n" > + " .endif\n" > + : [after_target] "=d" (after_target), > + [ret_addr] "=d" (ret_addr), > + [after_ex] "=d" (after_ex), > + [branch_addr] "=d" (branch_addr) > + ); > + > + report(after_target == branch_addr, "address calculated relative to BRAS"); > + report(ret_addr == after_ex, "return address after EX"); > + report_prefix_pop(); > +} > + > +/* > + * LOAD ADDRESS RELATIVE LONG. > + * If it is the target of an execute-type instruction, the address is relative > + * to the LARL. > + */ > +static void test_larl(void) > +{ > + uint64_t target, addr; > + > + report_prefix_push("LARL"); > + asm volatile ( ".pushsection .text.exrl_targets\n" > + "0: larl %[addr],0\n" > + " .popsection\n" > + > + " larl %[target],0b\n" > + " exrl 0,0b\n" > + : [target] "=d" (target), > + [addr] "=d" (addr) > + ); > + > + report(target == addr, "address calculated relative to LARL"); > + report_prefix_pop(); > +} > + > +/* LOAD LOGICAL RELATIVE LONG. > + * If it is the target of an execute-type instruction, the address is relative > + * to the LLGFRL. > + */ > +static void test_llgfrl(void) > +{ > + uint64_t target, value; > + > + report_prefix_push("LLGFRL"); > + asm volatile ( ".pushsection .text.exrl_targets\n" > + " .balign 4\n" > + //operand of llgfrl must be word aligned > + "0: llgfrl %[value],0\n" > + " .popsection\n" > + > + " llgfrl %[target],0b\n" > + //align (pad with nop), in case the wrong operand is used > + " .balignw 4,0x0707\n" > + " exrl 0,0b\n" > + : [target] "=d" (target), > + [value] "=d" (value) > + ); > + > + report(target == value, "loaded correct value"); > + report_prefix_pop(); > +} > + > +/* > + * COMPARE RELATIVE LONG > + * If it is the target of an execute-type instruction, the address is relative > + * to the CRL. > + */ > +static void test_crl(void) > +{ > + uint32_t program_mask, cc, crl_word; > + > + report_prefix_push("CRL"); > + asm volatile ( ".pushsection .text.exrl_targets\n" > + //operand of crl must be word aligned > + " .balign 4\n" > + "0: crl %[crl_word],0\n" > + " .popsection\n" > + > + " lrl %[crl_word],0b\n" > + //align (pad with nop), in case the wrong operand is used > + " .balignw 4,0x0707\n" > + " exrl 0,0b\n" > + " ipm %[program_mask]\n" > + : [program_mask] "=d" (program_mask), > + [crl_word] "=d" (crl_word) > + :: "cc" > + ); > + > + cc = program_mask >> 28; > + report(!cc, "operand compared to is relative to CRL"); > + report_prefix_pop(); > +} > + > +int main(int argc, char **argv) > +{ > + report_prefix_push("ex"); > + test_basr(); > + test_bras(); > + test_larl(); > + test_llgfrl(); > + test_crl(); > + report_prefix_pop(); > + > + return report_summary(); > +} > diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg > index d97eb5e9..b61faf07 100644 > --- a/s390x/unittests.cfg > +++ b/s390x/unittests.cfg > @@ -215,3 +215,6 @@ file = migration-skey.elf > smp = 2 > groups = migration > extra_params = -append '--parallel' > + > +[execute] > +file = ex.elf > diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml > index ad7949c9..a999f64a 100644 > --- a/.gitlab-ci.yml > +++ b/.gitlab-ci.yml > @@ -275,6 +275,7 @@ s390x-kvm: > - ACCEL=kvm ./run_tests.sh > selftest-setup intercept emulator sieve sthyi diag10 diag308 pfmf > cmm vector gs iep cpumodel diag288 stsi sclp-1g sclp-3g css skrf sie > + execute > | tee results.txt > - grep -q PASS results.txt && ! grep -q FAIL results.txt > only: > > base-commit: 20de8c3b54078ebc3df0b47344f9ce55bf52b7a5
