* Fix emulation of s390x instructions: CKSM, CLM, ICM, MC, CLGEBR(A)

* Remove useless and non-working s390x migration avocado tests
 * Fix loongarch CSRRD CPUID instruction when running on s390x hosts
 * Disable flaky s390x virtio-gpu test by default
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Merge tag 'pull-request-2023-07-24' of https://gitlab.com/thuth/qemu into staging

* Fix emulation of s390x instructions: CKSM, CLM, ICM, MC, CLGEBR(A)
* Remove useless and non-working s390x migration avocado tests
* Fix loongarch CSRRD CPUID instruction when running on s390x hosts
* Disable flaky s390x virtio-gpu test by default

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# gpg: Signature made Mon 24 Jul 2023 17:49:06 BST
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* tag 'pull-request-2023-07-24' of https://gitlab.com/thuth/qemu:
  tests/avocado/machine_s390_ccw_virtio: Skip the flaky virtio-gpu test by default
  target/loongarch: Fix the CSRRD CPUID instruction on big endian hosts
  tests/avocado/migration: Remove the malfunctioning s390x tests
  tests/tcg/s390x: Test VCKSM
  tests/tcg/s390x: Test STPQ
  tests/tcg/s390x: Test MC
  tests/tcg/s390x: Test ICM
  tests/tcg/s390x: Test CLM
  tests/tcg/s390x: Test CLGEBR and CGEBRA
  tests/tcg/s390x: Test CKSM
  target/s390x: Fix assertion failure in VFMIN/VFMAX with type 13
  target/s390x: Make MC raise specification exception when class >= 16
  target/s390x: Fix ICM with M3=0
  target/s390x: Fix CONVERT TO LOGICAL/FIXED with out-of-range inputs
  target/s390x: Fix CLM with M3=0
  target/s390x: Make CKSM raise an exception if R2 is odd

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/loongarch/cpu.h

@@ -342,6 +342,7 @@ typedef struct CPUArchState {
     uint64_t CSR_DBG;
     uint64_t CSR_DERA;
     uint64_t CSR_DSAVE;
+    uint64_t CSR_CPUID;
 
 #ifndef CONFIG_USER_ONLY
     LoongArchTLB  tlb[LOONGARCH_TLB_MAX];

target/loongarch/csr_helper.c

@@ -35,6 +35,15 @@ target_ulong helper_csrrd_pgd(CPULoongArchState *env)
     return v;
 }
 
+target_ulong helper_csrrd_cpuid(CPULoongArchState *env)
+{
+    LoongArchCPU *lac = env_archcpu(env);
+
+    env->CSR_CPUID = CPU(lac)->cpu_index;
+
+    return env->CSR_CPUID;
+}
+
 target_ulong helper_csrrd_tval(CPULoongArchState *env)
 {
     LoongArchCPU *cpu = env_archcpu(env);

target/loongarch/helper.h

@@ -98,6 +98,7 @@ DEF_HELPER_1(rdtime_d, i64, env)
 #ifndef CONFIG_USER_ONLY
 /* CSRs helper */
 DEF_HELPER_1(csrrd_pgd, i64, env)
+DEF_HELPER_1(csrrd_cpuid, i64, env)
 DEF_HELPER_1(csrrd_tval, i64, env)
 DEF_HELPER_2(csrwr_estat, i64, env, tl)
 DEF_HELPER_2(csrwr_asid, i64, env, tl)

target/loongarch/insn_trans/trans_privileged.c.inc

@@ -99,13 +99,7 @@ static const CSRInfo csr_info[] = {
     CSR_OFF(PWCH),
     CSR_OFF(STLBPS),
     CSR_OFF(RVACFG),
-    [LOONGARCH_CSR_CPUID] = {
+    CSR_OFF_FUNCS(CPUID, CSRFL_READONLY, gen_helper_csrrd_cpuid, NULL),
-        .offset = (int)offsetof(CPUState, cpu_index)
-                  - (int)offsetof(LoongArchCPU, env),
-        .flags = CSRFL_READONLY,
-        .readfn = NULL,
-        .writefn = NULL
-    },
     CSR_OFF_FLAGS(PRCFG1, CSRFL_READONLY),
     CSR_OFF_FLAGS(PRCFG2, CSRFL_READONLY),
     CSR_OFF_FLAGS(PRCFG3, CSRFL_READONLY),

target/s390x/tcg/excp_helper.c

@@ -639,7 +639,7 @@ void monitor_event(CPUS390XState *env,
 void HELPER(monitor_call)(CPUS390XState *env, uint64_t monitor_code,
                           uint32_t monitor_class)
 {
-    g_assert(monitor_class <= 0xff);
+    g_assert(monitor_class <= 0xf);
 
     if (env->cregs[8] & (0x8000 >> monitor_class)) {
         monitor_event(env, monitor_code, monitor_class, GETPC());

target/s390x/tcg/fpu_helper.c

@@ -52,7 +52,8 @@ uint8_t s390_softfloat_exc_to_ieee(unsigned int exc)
     s390_exc |= (exc & float_flag_divbyzero) ? S390_IEEE_MASK_DIVBYZERO : 0;
     s390_exc |= (exc & float_flag_overflow) ? S390_IEEE_MASK_OVERFLOW : 0;
     s390_exc |= (exc & float_flag_underflow) ? S390_IEEE_MASK_UNDERFLOW : 0;
-    s390_exc |= (exc & float_flag_inexact) ? S390_IEEE_MASK_INEXACT : 0;
+    s390_exc |= (exc & (float_flag_inexact | float_flag_invalid_cvti)) ?
+                S390_IEEE_MASK_INEXACT : 0;
 
     return s390_exc;
 }

target/s390x/tcg/insn-data.h.inc

@@ -157,7 +157,7 @@
     C(0xb2fa, NIAI,    E,     EH,  0, 0, 0, 0, 0, 0)
 
 /* CHECKSUM */
-    C(0xb241, CKSM,    RRE,   Z,   r1_o, ra2, new, r1_32, cksm, 0)
+    C(0xb241, CKSM,    RRE,   Z,   r1_o, ra2_E, new, r1_32, cksm, 0)
 
 /* COPY SIGN */
     F(0xb372, CPSDR,   RRF_b, FPSSH, f3, f2, new, f1, cps, 0, IF_AFP1 | IF_AFP2 | IF_AFP3)

target/s390x/tcg/mem_helper.c

@@ -667,6 +667,11 @@ uint32_t HELPER(clm)(CPUS390XState *env, uint32_t r1, uint32_t mask,
     HELPER_LOG("%s: r1 0x%x mask 0x%x addr 0x%" PRIx64 "\n", __func__, r1,
                mask, addr);
 
+    if (!mask) {
+        /* Recognize access exceptions for the first byte */
+        probe_read(env, addr, 1, cpu_mmu_index(env, false), ra);
+    }
+
     while (mask) {
         if (mask & 8) {
             uint8_t d = cpu_ldub_data_ra(env, addr, ra);

target/s390x/tcg/translate.c

@@ -2515,6 +2515,12 @@ static DisasJumpType op_icm(DisasContext *s, DisasOps *o)
         ccm = ((1ull << len) - 1) << pos;
         break;
 
+    case 0:
+        /* Recognize access exceptions for the first byte.  */
+        tcg_gen_qemu_ld_i64(tmp, o->in2, get_mem_index(s), MO_UB);
+        gen_op_movi_cc(s, 0);
+        return DISAS_NEXT;
+
     default:
         /* This is going to be a sequence of loads and inserts.  */
         pos = base + 32 - 8;
@@ -3171,9 +3177,9 @@ static DisasJumpType op_lcbb(DisasContext *s, DisasOps *o)
 
 static DisasJumpType op_mc(DisasContext *s, DisasOps *o)
 {
-    const uint16_t monitor_class = get_field(s, i2);
+    const uint8_t monitor_class = get_field(s, i2);
 
-    if (monitor_class & 0xff00) {
+    if (monitor_class & 0xf0) {
         gen_program_exception(s, PGM_SPECIFICATION);
         return DISAS_NORETURN;
     }
@@ -5779,6 +5785,12 @@ static void in2_ra2(DisasContext *s, DisasOps *o)
 }
 #define SPEC_in2_ra2 0
 
+static void in2_ra2_E(DisasContext *s, DisasOps *o)
+{
+    return in2_ra2(s, o);
+}
+#define SPEC_in2_ra2_E SPEC_r2_even
+
 static void in2_a2(DisasContext *s, DisasOps *o)
 {
     int x2 = have_field(s, x2) ? get_field(s, x2) : 0;

target/s390x/tcg/translate_vx.c.inc

@@ -3047,7 +3047,7 @@ static DisasJumpType op_vfmax(DisasContext *s, DisasOps *o)
     const uint8_t m5 = get_field(s, m5);
     gen_helper_gvec_3_ptr *fn;
 
-    if (m6 == 5 || m6 == 6 || m6 == 7 || m6 > 13) {
+    if (m6 == 5 || m6 == 6 || m6 == 7 || m6 >= 13) {
         gen_program_exception(s, PGM_SPECIFICATION);
         return DISAS_NORETURN;
     }

tests/avocado/machine_s390_ccw_virtio.py

@@ -159,7 +159,6 @@ class S390CCWVirtioMachine(QemuSystemTest):
                                           'MemTotal:         115640 kB')
 
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
     def test_s390x_fedora(self):
 
         """
@@ -229,6 +228,8 @@ class S390CCWVirtioMachine(QemuSystemTest):
         # writing to the framebuffer. Since the PPM is uncompressed, we then
         # can simply read the written "magic bytes" back from the PPM file to
         # check whether the framebuffer is working as expected.
+        # Unfortunately, this test is flaky, so we don't run it by default
+        if os.getenv('QEMU_TEST_FLAKY_TESTS'):
             self.log.info("Test screendump of virtio-gpu device")
             exec_command_and_wait_for_pattern(self,
                         'while ! (dmesg | grep gpudrmfb) ; do sleep 1 ; done',
@@ -254,6 +255,8 @@ class S390CCWVirtioMachine(QemuSystemTest):
                 self.assertEqual(line, b"255\n")
                 line = ppmfile.readline(256)
                 self.assertEqual(line, b"The quick fox jumps over a lazy dog\n")
+        else:
+            self.log.info("Skipped flaky screendump of virtio-gpu device test")
 
         # Hot-plug a virtio-crypto device and see whether it gets accepted
         self.log.info("Test hot-plug virtio-crypto device")

tests/avocado/migration.py

@@ -134,21 +134,3 @@ class PPC64(MigrationTest):
 
     def test_migration_with_exec(self):
         self.migration_with_exec()
-
-
-@skipUnless('s390x' in os.uname()[4], "host != target")
-class S390X(MigrationTest):
-    """
-    :avocado: tags=arch:s390x
-    :avocado: tags=machine:s390-ccw-virtio
-    :avocado: tags=cpu:qemu
-    """
-
-    def test_migration_with_tcp_localhost(self):
-        self.migration_with_tcp_localhost()
-
-    def test_migration_with_unix(self):
-        self.migration_with_unix()
-
-    def test_migration_with_exec(self):
-        self.migration_with_exec()

tests/tcg/s390x/Makefile.softmmu-target

@@ -16,13 +16,18 @@ LDFLAGS=-nostdlib -static
 
 ASM_TESTS =                                                                    \
     bal                                                                        \
+    cksm                                                                       \
+    clm                                                                        \
     exrl-ssm-early                                                             \
+    icm                                                                        \
     sam                                                                        \
     lpsw                                                                       \
     lpswe-early                                                                \
     lra                                                                        \
+    mc                                                                         \
     ssm-early                                                                  \
     stosm-early                                                                \
+    stpq                                                                       \
     unaligned-lowcore
 
 include $(S390X_SRC)/pgm-specification.mak

tests/tcg/s390x/Makefile.target

@@ -39,12 +39,17 @@ TESTS+=mxdb
 TESTS+=epsw
 TESTS+=larl
 TESTS+=mdeb
+TESTS+=cgebra
+TESTS+=clgebr
 
 cdsg: CFLAGS+=-pthread
 cdsg: LDFLAGS+=-pthread
 
 rxsbg: CFLAGS+=-O2
 
+cgebra: LDFLAGS+=-lm
+clgebr: LDFLAGS+=-lm
+
 include $(S390X_SRC)/pgm-specification.mak
 $(PGM_SPECIFICATION_TESTS): pgm-specification-user.o
 $(PGM_SPECIFICATION_TESTS): LDFLAGS+=pgm-specification-user.o
@@ -53,6 +58,7 @@ TESTS += $(PGM_SPECIFICATION_TESTS)
 Z13_TESTS=vistr
 Z13_TESTS+=lcbb
 Z13_TESTS+=locfhr
+Z13_TESTS+=vcksm
 $(Z13_TESTS): CFLAGS+=-march=z13 -O2
 TESTS+=$(Z13_TESTS)
 

tests/tcg/s390x/cgebra.c

@@ -0,0 +1,32 @@
+/*
+ * Test the CGEBRA instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <fenv.h>
+#include <stdlib.h>
+
+int main(void)
+{
+    float r2 = 1E+300;
+    long long r1;
+    int cc;
+
+    feclearexcept(FE_ALL_EXCEPT);
+    asm("cgebra %[r1],%[m3],%[r2],%[m4]\n"
+        "ipm %[cc]\n"
+        : [r1] "=r" (r1)
+        , [cc] "=r" (cc)
+        : [m3] "i" (5) /* round toward 0 */
+        , [r2] "f" (r2)
+        , [m4] "i" (8) /* bit 0 is set, but must be ignored; XxC is not set */
+        : "cc");
+    cc >>= 28;
+
+    assert(r1 == 0x7fffffffffffffffLL);
+    assert(cc == 3);
+    assert(fetestexcept(FE_ALL_EXCEPT) == (FE_INVALID | FE_INEXACT));
+
+    return EXIT_SUCCESS;
+}

tests/tcg/s390x/cksm.S

@@ -0,0 +1,29 @@
+    .org 0x8e
+program_interruption_code:
+    .org 0x1d0                         /* program new PSW */
+    .quad 0,pgm
+    .org 0x200                         /* lowcore padding */
+    .globl _start
+_start:
+    lmg %r0,%r1,cksm_args
+    cksm %r2,%r0
+    c %r2,cksm_exp
+    jne failure
+    .insn rre,0xb2410000,%r2,%r15      /* cksm %r2,%r15 */
+failure:
+    lpswe failure_psw
+pgm:
+    chhsi program_interruption_code,6  /* specification exception? */
+    jne failure
+    lpswe success_psw
+cksm_args:
+    .quad cksm_buf, 16
+cksm_buf:
+    .quad 0xaaaabbbbcccc0000, 0x12345678
+cksm_exp:
+    .long 0x89ab1234
+    .align 8
+success_psw:
+    .quad 0x2000000000000,0xfff        /* see is_special_wait_psw() */
+failure_psw:
+    .quad 0x2000000000000,0            /* disabled wait */

tests/tcg/s390x/clgebr.c

@@ -0,0 +1,32 @@
+/*
+ * Test the CLGEBR instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <fenv.h>
+#include <stdlib.h>
+
+int main(void)
+{
+    float r2 = -1;
+    long long r1;
+    int cc;
+
+    feclearexcept(FE_ALL_EXCEPT);
+    asm("clgebr %[r1],%[m3],%[r2],%[m4]\n"
+        "ipm %[cc]\n"
+        : [r1] "=r" (r1)
+        , [cc] "=r" (cc)
+        : [m3] "i" (5) /* round toward 0 */
+        , [r2] "f" (r2)
+        , [m4] "i" (8) /* bit 0 is set, but must be ignored; XxC is not set */
+        : "cc");
+    cc >>= 28;
+
+    assert(r1 == 0);
+    assert(cc == 3);
+    assert(fetestexcept(FE_ALL_EXCEPT) == (FE_INVALID | FE_INEXACT));
+
+    return EXIT_SUCCESS;
+}

tests/tcg/s390x/clm.S

@@ -0,0 +1,29 @@
+    .org 0x8e
+program_interruption_code:
+    .org 0x1d0                         /* program new PSW */
+    .quad 0,pgm
+    .org 0x200                         /* lowcore padding */
+    .globl _start
+_start:
+    lgrl %r0,op1
+    clm %r0,6,op2
+    jle failure
+    lgrl %r1,bad_addr
+    clm %r0,0,0(%r1)
+failure:
+    lpswe failure_psw
+pgm:
+    chhsi program_interruption_code,5  /* addressing exception? */
+    jne failure
+    lpswe success_psw
+    .align 8
+op1:
+    .quad 0x1234567887654321
+op2:
+    .quad 0x3456789abcdef012
+bad_addr:
+    .quad 0xffffffff00000000
+success_psw:
+    .quad 0x2000000000000,0xfff        /* see is_special_wait_psw() */
+failure_psw:
+    .quad 0x2000000000000,0            /* disabled wait */

tests/tcg/s390x/icm.S

@@ -0,0 +1,32 @@
+    .org 0x8e
+program_interruption_code:
+    .org 0x1d0                         /* program new PSW */
+    .quad 0,pgm
+    .org 0x200                         /* lowcore padding */
+    .globl _start
+_start:
+    lgrl %r0,op1
+    icm %r0,10,op2
+    cg %r0,exp
+    jne failure
+    lgrl %r1,bad_addr
+    icm %r0,0,0(%r1)
+failure:
+    lpswe failure_psw
+pgm:
+    chhsi program_interruption_code,5  /* addressing exception? */
+    jne failure
+    lpswe success_psw
+    .align 8
+op1:
+    .quad 0x1234567887654321
+op2:
+    .quad 0x0011223344556677
+exp:
+    .quad 0x1234567800651121
+bad_addr:
+    .quad 0xffffffff00000000
+success_psw:
+    .quad 0x2000000000000,0xfff        /* see is_special_wait_psw() */
+failure_psw:
+    .quad 0x2000000000000,0            /* disabled wait */

tests/tcg/s390x/mc.S

@@ -0,0 +1,56 @@
+    .org 0x8d
+ilc:
+    .org 0x8e
+program_interruption_code:
+    .org 0x94
+monitor_class:
+    .org 0xb0
+monitor_code:
+    .org 0x150
+program_old_psw:
+    .org 0x1d0                              /* program new PSW */
+    .quad 0x180000000,pgm                   /* 64-bit mode */
+    .org 0x200                              /* lowcore padding */
+    .globl _start
+_start:
+    stctg %c8,%c8,c8                        /* enable only monitor class 1 */
+    mvhhi c8+6,0x4000
+    lctlg %c8,%c8,c8
+mc_nop:
+    mc 123,0
+mc_monitor_event:
+    mc 321,1
+    j failure
+mc_specification:
+    mc 333,16
+    j failure
+pgm:
+    lgrl %r0,program_old_psw+8              /* ilc adjustment */
+    llgc %r1,ilc
+    sgr %r0,%r1
+    larl %r1,mc_monitor_event               /* dispatch based on old PSW */
+    cgrje %r0,%r1,pgm_monitor_event
+    larl %r1,mc_specification
+    cgrje %r0,%r1,pgm_specification
+    j failure
+pgm_monitor_event:
+    chhsi program_interruption_code,0x40    /* monitor event? */
+    jne failure
+    chhsi monitor_class,1                   /* class from mc_monitor_event? */
+    jne failure
+    cghsi monitor_code,321                  /* code from mc_monitor_event? */
+    jne failure
+    j mc_specification                      /* next test */
+pgm_specification:
+    chhsi program_interruption_code,6       /* specification exception? */
+    jne failure
+    lpswe success_psw
+failure:
+    lpswe failure_psw
+    .align 8
+c8:
+    .quad 0
+success_psw:
+    .quad 0x2000000000000,0xfff             /* see is_special_wait_psw() */
+failure_psw:
+    .quad 0x2000000000000,0                 /* disabled wait */

tests/tcg/s390x/stpq.S

@@ -0,0 +1,20 @@
+    .org 0x200                         /* lowcore padding */
+    .globl _start
+_start:
+    lgrl %r0,value
+    lgrl %r1,value+8
+    stpq %r0,stored_value
+    clc stored_value(16),value
+    jne failure
+    lpswe success_psw
+failure:
+    lpswe failure_psw
+    .align 16
+value:
+    .quad 0x1234567887654321, 0x8765432112345678
+stored_value:
+    .quad 0, 0
+success_psw:
+    .quad 0x2000000000000,0xfff        /* see is_special_wait_psw() */
+failure_psw:
+    .quad 0x2000000000000,0            /* disabled wait */

tests/tcg/s390x/vcksm.c

@@ -0,0 +1,31 @@
+/*
+ * Test the VCKSM instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include "vx.h"
+
+int main(void)
+{
+    S390Vector v1;
+    S390Vector v2 = {
+        .d[0] = 0xb2261c8140edce49ULL,
+        .d[1] = 0x387bf5a433af39d1ULL,
+    };
+    S390Vector v3 = {
+        .d[0] = 0x73b03d2c7f9e654eULL,
+        .d[1] = 0x23d74e51fb479877ULL,
+    };
+    S390Vector exp = {.d[0] = 0xdedd7f8eULL, .d[1] = 0ULL};
+
+    asm volatile("vcksm %[v1],%[v2],%[v3]"
+                 : [v1] "=v" (v1.v)
+                 : [v2] "v" (v2.v)
+                 , [v3] "v" (v3.v));
+    assert(memcmp(&v1, &exp, sizeof(v1)) == 0);
+
+    return EXIT_SUCCESS;
+}

tests/tcg/s390x/vx.h

@@ -1,6 +1,8 @@
 #ifndef QEMU_TESTS_S390X_VX_H
 #define QEMU_TESTS_S390X_VX_H
 
+#include <stdint.h>
+
 typedef union S390Vector {
     uint64_t d[2];  /* doubleword */
     uint32_t w[4];  /* word */