Merge tag 'pull-lu-20230901' of https://gitlab.com/rth7680/qemu into staging

linux-user: Rewrite and improve /proc/pid/maps
linux-user: Fix shmdt and improve shm region tracking
linux-user: Remove ELF_START_MMAP and image_info.start_mmap

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* tag 'pull-lu-20230901' of https://gitlab.com/rth7680/qemu:
  linux-user: Track shm regions with an interval tree
  linux-user: Fix shmdt
  linux-user: Use WITH_MMAP_LOCK_GUARD in target_{shmat,shmdt}
  linux-user: Move shmat and shmdt implementations to mmap.c
  linux-user: Remove ELF_START_MMAP and image_info.start_mmap
  linux-user: Emulate the Anonymous: keyword in /proc/self/smaps
  linux-user: Show heap address in /proc/pid/maps
  linux-user: Adjust brk for load_bias
  linux-user: Use walk_memory_regions for open_self_maps
  util/selfmap: Use dev_t and ino_t in MapInfo
  linux-user: Emulate /proc/cpuinfo for Alpha
  linux-user: Emulate /proc/cpuinfo on aarch64 and arm
  linux-user: Split out cpu/target_proc.h

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

27 files changed, 818 insertions, 429 deletions

diff --git a/linux-user/aarch64/target_proc.h b/linux-user/aarch64/target_proc.h
new file mode 100644
index 0000000000..907df4dcd2
--- /dev/null
+++ b/linux-user/aarch64/target_proc.h
@@ -0,0 +1 @@
+#include "../arm/target_proc.h"
diff --git a/linux-user/alpha/target_proc.h b/linux-user/alpha/target_proc.h
new file mode 100644
index 0000000000..dac37dffc9
--- /dev/null
+++ b/linux-user/alpha/target_proc.h
@@ -0,0 +1,67 @@
+/*
+ * Alpha specific proc functions for linux-user
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef ALPHA_TARGET_PROC_H
+#define ALPHA_TARGET_PROC_H
+
+static int open_cpuinfo(CPUArchState *cpu_env, int fd)
+{
+    int max_cpus = sysconf(_SC_NPROCESSORS_CONF);
+    int num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+    unsigned long cpu_mask;
+    char model[32];
+    const char *p, *q;
+    int t;
+
+    p = object_class_get_name(OBJECT_CLASS(CPU_GET_CLASS(env_cpu(cpu_env))));
+    q = strchr(p, '-');
+    t = q - p;
+    assert(t < sizeof(model));
+    memcpy(model, p, t);
+    model[t] = 0;
+
+    t = sched_getaffinity(getpid(), sizeof(cpu_mask), (cpu_set_t *)&cpu_mask);
+    if (t < 0) {
+        if (num_cpus >= sizeof(cpu_mask) * 8) {
+            cpu_mask = -1;
+        } else {
+            cpu_mask = (1UL << num_cpus) - 1;
+        }
+    }
+
+    dprintf(fd,
+            "cpu\t\t\t: Alpha\n"
+            "cpu model\t\t: %s\n"
+            "cpu variation\t\t: 0\n"
+            "cpu revision\t\t: 0\n"
+            "cpu serial number\t: JA00000000\n"
+            "system type\t\t: QEMU\n"
+            "system variation\t: QEMU_v" QEMU_VERSION "\n"
+            "system revision\t\t: 0\n"
+            "system serial number\t: AY00000000\n"
+            "cycle frequency [Hz]\t: 250000000\n"
+            "timer frequency [Hz]\t: 250.00\n"
+            "page size [bytes]\t: %d\n"
+            "phys. address bits\t: %d\n"
+            "max. addr. space #\t: 255\n"
+            "BogoMIPS\t\t: 2500.00\n"
+            "kernel unaligned acc\t: 0 (pc=0,va=0)\n"
+            "user unaligned acc\t: 0 (pc=0,va=0)\n"
+            "platform string\t\t: AlphaServer QEMU user-mode VM\n"
+            "cpus detected\t\t: %d\n"
+            "cpus active\t\t: %d\n"
+            "cpu active mask\t\t: %016lx\n"
+            "L1 Icache\t\t: n/a\n"
+            "L1 Dcache\t\t: n/a\n"
+            "L2 cache\t\t: n/a\n"
+            "L3 cache\t\t: n/a\n",
+            model, TARGET_PAGE_SIZE, TARGET_PHYS_ADDR_SPACE_BITS,
+            max_cpus, num_cpus, cpu_mask);
+
+    return 0;
+}
+#define HAVE_ARCH_PROC_CPUINFO
+
+#endif /* ALPHA_TARGET_PROC_H */
diff --git a/linux-user/arm/target_proc.h b/linux-user/arm/target_proc.h
new file mode 100644
index 0000000000..ac75af9ca6
--- /dev/null
+++ b/linux-user/arm/target_proc.h
@@ -0,0 +1,101 @@
+/*
+ * Arm specific proc functions for linux-user
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef ARM_TARGET_PROC_H
+#define ARM_TARGET_PROC_H
+
+static int open_cpuinfo(CPUArchState *cpu_env, int fd)
+{
+    ARMCPU *cpu = env_archcpu(cpu_env);
+    int arch, midr_rev, midr_part, midr_var, midr_impl;
+    target_ulong elf_hwcap = get_elf_hwcap();
+    target_ulong elf_hwcap2 = get_elf_hwcap2();
+    const char *elf_name;
+    int num_cpus, len_part, len_var;
+
+#if TARGET_BIG_ENDIAN
+# define END_SUFFIX "b"
+#else
+# define END_SUFFIX "l"
+#endif
+
+    arch = 8;
+    elf_name = "v8" END_SUFFIX;
+    midr_rev = FIELD_EX32(cpu->midr, MIDR_EL1, REVISION);
+    midr_part = FIELD_EX32(cpu->midr, MIDR_EL1, PARTNUM);
+    midr_var = FIELD_EX32(cpu->midr, MIDR_EL1, VARIANT);
+    midr_impl = FIELD_EX32(cpu->midr, MIDR_EL1, IMPLEMENTER);
+    len_part = 3;
+    len_var = 1;
+
+#ifndef TARGET_AARCH64
+    /* For simplicity, treat ARMv8 as an arm64 kernel with CONFIG_COMPAT. */
+    if (!arm_feature(&cpu->env, ARM_FEATURE_V8)) {
+        if (arm_feature(&cpu->env, ARM_FEATURE_V7)) {
+            arch = 7;
+            midr_var = (cpu->midr >> 16) & 0x7f;
+            len_var = 2;
+            if (arm_feature(&cpu->env, ARM_FEATURE_M)) {
+                elf_name = "armv7m" END_SUFFIX;
+            } else {
+                elf_name = "armv7" END_SUFFIX;
+            }
+        } else {
+            midr_part = cpu->midr >> 4;
+            len_part = 7;
+            if (arm_feature(&cpu->env, ARM_FEATURE_V6)) {
+                arch = 6;
+                elf_name = "armv6" END_SUFFIX;
+            } else if (arm_feature(&cpu->env, ARM_FEATURE_V5)) {
+                arch = 5;
+                elf_name = "armv5t" END_SUFFIX;
+            } else {
+                arch = 4;
+                elf_name = "armv4" END_SUFFIX;
+            }
+        }
+    }
+#endif
+
+#undef END_SUFFIX
+
+    num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+    for (int i = 0; i < num_cpus; i++) {
+        dprintf(fd,
+                "processor\t: %d\n"
+                "model name\t: ARMv%d Processor rev %d (%s)\n"
+                "BogoMIPS\t: 100.00\n"
+                "Features\t:",
+                i, arch, midr_rev, elf_name);
+
+        for (target_ulong j = elf_hwcap; j ; j &= j - 1) {
+            dprintf(fd, " %s", elf_hwcap_str(ctz64(j)));
+        }
+        for (target_ulong j = elf_hwcap2; j ; j &= j - 1) {
+            dprintf(fd, " %s", elf_hwcap2_str(ctz64(j)));
+        }
+
+        dprintf(fd, "\n"
+                "CPU implementer\t: 0x%02x\n"
+                "CPU architecture: %d\n"
+                "CPU variant\t: 0x%0*x\n",
+                midr_impl, arch, len_var, midr_var);
+        if (arch >= 7) {
+            dprintf(fd, "CPU part\t: 0x%0*x\n", len_part, midr_part);
+        }
+        dprintf(fd, "CPU revision\t: %d\n\n", midr_rev);
+    }
+
+    if (arch < 8) {
+        dprintf(fd, "Hardware\t: QEMU v%s %s\n", QEMU_VERSION,
+                cpu->dtb_compatible ? : "");
+        dprintf(fd, "Revision\t: 0000\n");
+        dprintf(fd, "Serial\t\t: 0000000000000000\n");
+    }
+    return 0;
+}
+#define HAVE_ARCH_PROC_CPUINFO
+
+#endif /* ARM_TARGET_PROC_H */
diff --git a/linux-user/cris/target_proc.h b/linux-user/cris/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/cris/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 92b981c445..a5b28fa3e7 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -143,8 +143,6 @@ static uint32_t get_elf_hwcap(void)
 }
 
 #ifdef TARGET_X86_64
-#define ELF_START_MMAP 0x2aaaaab000ULL
-
 #define ELF_CLASS      ELFCLASS64
 #define ELF_ARCH       EM_X86_64
 
@@ -221,8 +219,6 @@ static bool init_guest_commpage(void)
 #endif
 #else
 
-#define ELF_START_MMAP 0x80000000
-
 /*
  * This is used to ensure we don't load something for the wrong architecture.
  */
@@ -308,8 +304,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs, const CPUX86State *en
 #ifndef TARGET_AARCH64
 /* 32 bit ARM definitions */
 
-#define ELF_START_MMAP 0x80000000
-
 #define ELF_ARCH        EM_ARM
 #define ELF_CLASS       ELFCLASS32
 #define EXSTACK_DEFAULT true
@@ -466,7 +460,7 @@ static bool init_guest_commpage(void)
 #define ELF_HWCAP get_elf_hwcap()
 #define ELF_HWCAP2 get_elf_hwcap2()
 
-static uint32_t get_elf_hwcap(void)
+uint32_t get_elf_hwcap(void)
 {
     ARMCPU *cpu = ARM_CPU(thread_cpu);
     uint32_t hwcaps = 0;
@@ -508,7 +502,7 @@ static uint32_t get_elf_hwcap(void)
     return hwcaps;
 }
 
-static uint32_t get_elf_hwcap2(void)
+uint32_t get_elf_hwcap2(void)
 {
     ARMCPU *cpu = ARM_CPU(thread_cpu);
     uint32_t hwcaps = 0;
@@ -521,6 +515,49 @@ static uint32_t get_elf_hwcap2(void)
     return hwcaps;
 }
 
+const char *elf_hwcap_str(uint32_t bit)
+{
+    static const char *hwcap_str[] = {
+    [__builtin_ctz(ARM_HWCAP_ARM_SWP      )] = "swp",
+    [__builtin_ctz(ARM_HWCAP_ARM_HALF     )] = "half",
+    [__builtin_ctz(ARM_HWCAP_ARM_THUMB    )] = "thumb",
+    [__builtin_ctz(ARM_HWCAP_ARM_26BIT    )] = "26bit",
+    [__builtin_ctz(ARM_HWCAP_ARM_FAST_MULT)] = "fast_mult",
+    [__builtin_ctz(ARM_HWCAP_ARM_FPA      )] = "fpa",
+    [__builtin_ctz(ARM_HWCAP_ARM_VFP      )] = "vfp",
+    [__builtin_ctz(ARM_HWCAP_ARM_EDSP     )] = "edsp",
+    [__builtin_ctz(ARM_HWCAP_ARM_JAVA     )] = "java",
+    [__builtin_ctz(ARM_HWCAP_ARM_IWMMXT   )] = "iwmmxt",
+    [__builtin_ctz(ARM_HWCAP_ARM_CRUNCH   )] = "crunch",
+    [__builtin_ctz(ARM_HWCAP_ARM_THUMBEE  )] = "thumbee",
+    [__builtin_ctz(ARM_HWCAP_ARM_NEON     )] = "neon",
+    [__builtin_ctz(ARM_HWCAP_ARM_VFPv3    )] = "vfpv3",
+    [__builtin_ctz(ARM_HWCAP_ARM_VFPv3D16 )] = "vfpv3d16",
+    [__builtin_ctz(ARM_HWCAP_ARM_TLS      )] = "tls",
+    [__builtin_ctz(ARM_HWCAP_ARM_VFPv4    )] = "vfpv4",
+    [__builtin_ctz(ARM_HWCAP_ARM_IDIVA    )] = "idiva",
+    [__builtin_ctz(ARM_HWCAP_ARM_IDIVT    )] = "idivt",
+    [__builtin_ctz(ARM_HWCAP_ARM_VFPD32   )] = "vfpd32",
+    [__builtin_ctz(ARM_HWCAP_ARM_LPAE     )] = "lpae",
+    [__builtin_ctz(ARM_HWCAP_ARM_EVTSTRM  )] = "evtstrm",
+    };
+
+    return bit < ARRAY_SIZE(hwcap_str) ? hwcap_str[bit] : NULL;
+}
+
+const char *elf_hwcap2_str(uint32_t bit)
+{
+    static const char *hwcap_str[] = {
+    [__builtin_ctz(ARM_HWCAP2_ARM_AES  )] = "aes",
+    [__builtin_ctz(ARM_HWCAP2_ARM_PMULL)] = "pmull",
+    [__builtin_ctz(ARM_HWCAP2_ARM_SHA1 )] = "sha1",
+    [__builtin_ctz(ARM_HWCAP2_ARM_SHA2 )] = "sha2",
+    [__builtin_ctz(ARM_HWCAP2_ARM_CRC32)] = "crc32",
+    };
+
+    return bit < ARRAY_SIZE(hwcap_str) ? hwcap_str[bit] : NULL;
+}
+
 #undef GET_FEATURE
 #undef GET_FEATURE_ID
 
@@ -557,7 +594,6 @@ static const char *get_elf_platform(void)
 
 #else
 /* 64 bit ARM definitions */
-#define ELF_START_MMAP 0x80000000
 
 #define ELF_ARCH        EM_AARCH64
 #define ELF_CLASS       ELFCLASS64
@@ -668,7 +704,7 @@ enum {
 #define GET_FEATURE_ID(feat, hwcap) \
     do { if (cpu_isar_feature(feat, cpu)) { hwcaps |= hwcap; } } while (0)
 
-static uint32_t get_elf_hwcap(void)
+uint32_t get_elf_hwcap(void)
 {
     ARMCPU *cpu = ARM_CPU(thread_cpu);
     uint32_t hwcaps = 0;
@@ -706,7 +742,7 @@ static uint32_t get_elf_hwcap(void)
     return hwcaps;
 }
 
-static uint32_t get_elf_hwcap2(void)
+uint32_t get_elf_hwcap2(void)
 {
     ARMCPU *cpu = ARM_CPU(thread_cpu);
     uint32_t hwcaps = 0;
@@ -741,6 +777,85 @@ static uint32_t get_elf_hwcap2(void)
     return hwcaps;
 }
 
+const char *elf_hwcap_str(uint32_t bit)
+{
+    static const char *hwcap_str[] = {
+    [__builtin_ctz(ARM_HWCAP_A64_FP      )] = "fp",
+    [__builtin_ctz(ARM_HWCAP_A64_ASIMD   )] = "asimd",
+    [__builtin_ctz(ARM_HWCAP_A64_EVTSTRM )] = "evtstrm",
+    [__builtin_ctz(ARM_HWCAP_A64_AES     )] = "aes",
+    [__builtin_ctz(ARM_HWCAP_A64_PMULL   )] = "pmull",
+    [__builtin_ctz(ARM_HWCAP_A64_SHA1    )] = "sha1",
+    [__builtin_ctz(ARM_HWCAP_A64_SHA2    )] = "sha2",
+    [__builtin_ctz(ARM_HWCAP_A64_CRC32   )] = "crc32",
+    [__builtin_ctz(ARM_HWCAP_A64_ATOMICS )] = "atomics",
+    [__builtin_ctz(ARM_HWCAP_A64_FPHP    )] = "fphp",
+    [__builtin_ctz(ARM_HWCAP_A64_ASIMDHP )] = "asimdhp",
+    [__builtin_ctz(ARM_HWCAP_A64_CPUID   )] = "cpuid",
+    [__builtin_ctz(ARM_HWCAP_A64_ASIMDRDM)] = "asimdrdm",
+    [__builtin_ctz(ARM_HWCAP_A64_JSCVT   )] = "jscvt",
+    [__builtin_ctz(ARM_HWCAP_A64_FCMA    )] = "fcma",
+    [__builtin_ctz(ARM_HWCAP_A64_LRCPC   )] = "lrcpc",
+    [__builtin_ctz(ARM_HWCAP_A64_DCPOP   )] = "dcpop",
+    [__builtin_ctz(ARM_HWCAP_A64_SHA3    )] = "sha3",
+    [__builtin_ctz(ARM_HWCAP_A64_SM3     )] = "sm3",
+    [__builtin_ctz(ARM_HWCAP_A64_SM4     )] = "sm4",
+    [__builtin_ctz(ARM_HWCAP_A64_ASIMDDP )] = "asimddp",
+    [__builtin_ctz(ARM_HWCAP_A64_SHA512  )] = "sha512",
+    [__builtin_ctz(ARM_HWCAP_A64_SVE     )] = "sve",
+    [__builtin_ctz(ARM_HWCAP_A64_ASIMDFHM)] = "asimdfhm",
+    [__builtin_ctz(ARM_HWCAP_A64_DIT     )] = "dit",
+    [__builtin_ctz(ARM_HWCAP_A64_USCAT   )] = "uscat",
+    [__builtin_ctz(ARM_HWCAP_A64_ILRCPC  )] = "ilrcpc",
+    [__builtin_ctz(ARM_HWCAP_A64_FLAGM   )] = "flagm",
+    [__builtin_ctz(ARM_HWCAP_A64_SSBS    )] = "ssbs",
+    [__builtin_ctz(ARM_HWCAP_A64_SB      )] = "sb",
+    [__builtin_ctz(ARM_HWCAP_A64_PACA    )] = "paca",
+    [__builtin_ctz(ARM_HWCAP_A64_PACG    )] = "pacg",
+    };
+
+    return bit < ARRAY_SIZE(hwcap_str) ? hwcap_str[bit] : NULL;
+}
+
+const char *elf_hwcap2_str(uint32_t bit)
+{
+    static const char *hwcap_str[] = {
+    [__builtin_ctz(ARM_HWCAP2_A64_DCPODP       )] = "dcpodp",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVE2         )] = "sve2",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVEAES       )] = "sveaes",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVEPMULL     )] = "svepmull",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVEBITPERM   )] = "svebitperm",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVESHA3      )] = "svesha3",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVESM4       )] = "svesm4",
+    [__builtin_ctz(ARM_HWCAP2_A64_FLAGM2       )] = "flagm2",
+    [__builtin_ctz(ARM_HWCAP2_A64_FRINT        )] = "frint",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVEI8MM      )] = "svei8mm",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVEF32MM     )] = "svef32mm",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVEF64MM     )] = "svef64mm",
+    [__builtin_ctz(ARM_HWCAP2_A64_SVEBF16      )] = "svebf16",
+    [__builtin_ctz(ARM_HWCAP2_A64_I8MM         )] = "i8mm",
+    [__builtin_ctz(ARM_HWCAP2_A64_BF16         )] = "bf16",
+    [__builtin_ctz(ARM_HWCAP2_A64_DGH          )] = "dgh",
+    [__builtin_ctz(ARM_HWCAP2_A64_RNG          )] = "rng",
+    [__builtin_ctz(ARM_HWCAP2_A64_BTI          )] = "bti",
+    [__builtin_ctz(ARM_HWCAP2_A64_MTE          )] = "mte",
+    [__builtin_ctz(ARM_HWCAP2_A64_ECV          )] = "ecv",
+    [__builtin_ctz(ARM_HWCAP2_A64_AFP          )] = "afp",
+    [__builtin_ctz(ARM_HWCAP2_A64_RPRES        )] = "rpres",
+    [__builtin_ctz(ARM_HWCAP2_A64_MTE3         )] = "mte3",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME          )] = "sme",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME_I16I64   )] = "sme_i16i64",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME_F64F64   )] = "sme_f64f64",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME_I8I32    )] = "sme_i8i32",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME_F16F32   )] = "sme_f16f32",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME_B16F32   )] = "sme_b16f32",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME_F32F32   )] = "sme_f32f32",
+    [__builtin_ctz(ARM_HWCAP2_A64_SME_FA64     )] = "sme_fa64",
+    };
+
+    return bit < ARRAY_SIZE(hwcap_str) ? hwcap_str[bit] : NULL;
+}
+
 #undef GET_FEATURE_ID
 
 #endif /* not TARGET_AARCH64 */
@@ -749,7 +864,6 @@ static uint32_t get_elf_hwcap2(void)
 #ifdef TARGET_SPARC
 #ifdef TARGET_SPARC64
 
-#define ELF_START_MMAP 0x80000000
 #define ELF_HWCAP  (HWCAP_SPARC_FLUSH | HWCAP_SPARC_STBAR | HWCAP_SPARC_SWAP \
                     | HWCAP_SPARC_MULDIV | HWCAP_SPARC_V9)
 #ifndef TARGET_ABI32
@@ -761,7 +875,6 @@ static uint32_t get_elf_hwcap2(void)
 #define ELF_CLASS   ELFCLASS64
 #define ELF_ARCH    EM_SPARCV9
 #else
-#define ELF_START_MMAP 0x80000000
 #define ELF_HWCAP  (HWCAP_SPARC_FLUSH | HWCAP_SPARC_STBAR | HWCAP_SPARC_SWAP \
                     | HWCAP_SPARC_MULDIV)
 #define ELF_CLASS   ELFCLASS32
@@ -783,7 +896,6 @@ static inline void init_thread(struct target_pt_regs *regs,
 #ifdef TARGET_PPC
 
 #define ELF_MACHINE    PPC_ELF_MACHINE
-#define ELF_START_MMAP 0x80000000
 
 #if defined(TARGET_PPC64)
 
@@ -986,8 +1098,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs, const CPUPPCState *en
 
 #ifdef TARGET_LOONGARCH64
 
-#define ELF_START_MMAP 0x80000000
-
 #define ELF_CLASS   ELFCLASS64
 #define ELF_ARCH    EM_LOONGARCH
 #define EXSTACK_DEFAULT true
@@ -1078,8 +1188,6 @@ static uint32_t get_elf_hwcap(void)
 
 #ifdef TARGET_MIPS
 
-#define ELF_START_MMAP 0x80000000
-
 #ifdef TARGET_MIPS64
 #define ELF_CLASS   ELFCLASS64
 #else
@@ -1237,8 +1345,6 @@ static uint32_t get_elf_hwcap(void)
 
 #ifdef TARGET_MICROBLAZE
 
-#define ELF_START_MMAP 0x80000000
-
 #define elf_check_arch(x) ( (x) == EM_MICROBLAZE || (x) == EM_MICROBLAZE_OLD)
 
 #define ELF_CLASS   ELFCLASS32
@@ -1279,8 +1385,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs, const CPUMBState *env
 
 #ifdef TARGET_NIOS2
 
-#define ELF_START_MMAP 0x80000000
-
 #define elf_check_arch(x) ((x) == EM_ALTERA_NIOS2)
 
 #define ELF_CLASS   ELFCLASS32
@@ -1376,8 +1480,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs,
 
 #ifdef TARGET_OPENRISC
 
-#define ELF_START_MMAP 0x08000000
-
 #define ELF_ARCH EM_OPENRISC
 #define ELF_CLASS ELFCLASS32
 #define ELF_DATA  ELFDATA2MSB
@@ -1414,8 +1516,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs,
 
 #ifdef TARGET_SH4
 
-#define ELF_START_MMAP 0x80000000
-
 #define ELF_CLASS ELFCLASS32
 #define ELF_ARCH  EM_SH
 
@@ -1496,8 +1596,6 @@ static uint32_t get_elf_hwcap(void)
 
 #ifdef TARGET_CRIS
 
-#define ELF_START_MMAP 0x80000000
-
 #define ELF_CLASS ELFCLASS32
 #define ELF_ARCH  EM_CRIS
 
@@ -1513,8 +1611,6 @@ static inline void init_thread(struct target_pt_regs *regs,
 
 #ifdef TARGET_M68K
 
-#define ELF_START_MMAP 0x80000000
-
 #define ELF_CLASS       ELFCLASS32
 #define ELF_ARCH        EM_68K
 
@@ -1564,8 +1660,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs, const CPUM68KState *e
 
 #ifdef TARGET_ALPHA
 
-#define ELF_START_MMAP (0x30000000000ULL)
-
 #define ELF_CLASS      ELFCLASS64
 #define ELF_ARCH       EM_ALPHA
 
@@ -1583,8 +1677,6 @@ static inline void init_thread(struct target_pt_regs *regs,
 
 #ifdef TARGET_S390X
 
-#define ELF_START_MMAP (0x20000000000ULL)
-
 #define ELF_CLASS	ELFCLASS64
 #define ELF_DATA	ELFDATA2MSB
 #define ELF_ARCH	EM_S390
@@ -1695,7 +1787,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs,
 
 #ifdef TARGET_RISCV
 
-#define ELF_START_MMAP 0x80000000
 #define ELF_ARCH  EM_RISCV
 
 #ifdef TARGET_RISCV32
@@ -1731,7 +1822,6 @@ static inline void init_thread(struct target_pt_regs *regs,
 
 #ifdef TARGET_HPPA
 
-#define ELF_START_MMAP  0x80000000
 #define ELF_CLASS       ELFCLASS32
 #define ELF_ARCH        EM_PARISC
 #define ELF_PLATFORM    "PARISC"
@@ -1783,8 +1873,6 @@ static bool init_guest_commpage(void)
 
 #ifdef TARGET_XTENSA
 
-#define ELF_START_MMAP 0x20000000
-
 #define ELF_CLASS       ELFCLASS32
 #define ELF_ARCH        EM_XTENSA
 
@@ -1850,8 +1938,6 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs,
 
 #ifdef TARGET_HEXAGON
 
-#define ELF_START_MMAP 0x20000000
-
 #define ELF_CLASS       ELFCLASS32
 #define ELF_ARCH        EM_HEXAGON
 
@@ -3205,7 +3291,7 @@ static void load_elf_image(const char *image_name, int image_fd,
     info->start_data = -1;
     info->end_data = 0;
     /* Usual start for brk is after all sections of the main executable. */
-    info->brk = TARGET_PAGE_ALIGN(hiaddr);
+    info->brk = TARGET_PAGE_ALIGN(hiaddr + load_bias);
     info->elf_flags = ehdr->e_flags;
 
     prot_exec = PROT_EXEC;
@@ -3568,8 +3654,6 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
     interp_info.fp_abi = MIPS_ABI_FP_UNKNOWN;
 #endif
 
-    info->start_mmap = (abi_ulong)ELF_START_MMAP;
-
     load_elf_image(bprm->filename, bprm->fd, info,
                    &elf_interpreter, bprm->buf);
 
diff --git a/linux-user/hexagon/target_proc.h b/linux-user/hexagon/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/hexagon/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/hppa/target_proc.h b/linux-user/hppa/target_proc.h
new file mode 100644
index 0000000000..9340c3b6af
--- /dev/null
+++ b/linux-user/hppa/target_proc.h
@@ -0,0 +1,26 @@
+/*
+ * HPPA specific proc functions for linux-user
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef HPPA_TARGET_PROC_H
+#define HPPA_TARGET_PROC_H
+
+static int open_cpuinfo(CPUArchState *cpu_env, int fd)
+{
+    int i, num_cpus;
+
+    num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+    for (i = 0; i < num_cpus; i++) {
+        dprintf(fd, "processor\t: %d\n", i);
+        dprintf(fd, "cpu family\t: PA-RISC 1.1e\n");
+        dprintf(fd, "cpu\t\t: PA7300LC (PCX-L2)\n");
+        dprintf(fd, "capabilities\t: os32\n");
+        dprintf(fd, "model\t\t: 9000/778/B160L - "
+                    "Merlin L2 160 QEMU (9000/778/B160L)\n\n");
+    }
+    return 0;
+}
+#define HAVE_ARCH_PROC_CPUINFO
+
+#endif /* HPPA_TARGET_PROC_H */
diff --git a/linux-user/i386/target_proc.h b/linux-user/i386/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/i386/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/loader.h b/linux-user/loader.h
index 59cbeacf24..324e5c872a 100644
--- a/linux-user/loader.h
+++ b/linux-user/loader.h
@@ -56,9 +56,13 @@ abi_long memcpy_to_target(abi_ulong dest, const void *src,
 
 extern unsigned long guest_stack_size;
 
-#ifdef TARGET_S390X
+#if defined(TARGET_S390X) || defined(TARGET_AARCH64) || defined(TARGET_ARM)
 uint32_t get_elf_hwcap(void);
 const char *elf_hwcap_str(uint32_t bit);
 #endif
+#if defined(TARGET_AARCH64) || defined(TARGET_ARM)
+uint32_t get_elf_hwcap2(void);
+const char *elf_hwcap2_str(uint32_t bit);
+#endif
 
 #endif /* LINUX_USER_LOADER_H */
diff --git a/linux-user/loongarch64/target_proc.h b/linux-user/loongarch64/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/loongarch64/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/m68k/target_proc.h b/linux-user/m68k/target_proc.h
new file mode 100644
index 0000000000..3df8f28e22
--- /dev/null
+++ b/linux-user/m68k/target_proc.h
@@ -0,0 +1,16 @@
+/*
+ * M68K specific proc functions for linux-user
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef M68K_TARGET_PROC_H
+#define M68K_TARGET_PROC_H
+
+static int open_hardware(CPUArchState *cpu_env, int fd)
+{
+    dprintf(fd, "Model:\t\tqemu-m68k\n");
+    return 0;
+}
+#define HAVE_ARCH_PROC_HARDWARE
+
+#endif /* M68K_TARGET_PROC_H */
diff --git a/linux-user/microblaze/target_proc.h b/linux-user/microblaze/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/microblaze/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/mips/target_proc.h b/linux-user/mips/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/mips/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/mips64/target_proc.h b/linux-user/mips64/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/mips64/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/mmap.c b/linux-user/mmap.c
index 9aab48d4a3..8eaf57b208 100644
--- a/linux-user/mmap.c
+++ b/linux-user/mmap.c
@@ -17,12 +17,14 @@
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 #include "qemu/osdep.h"
+#include <sys/shm.h>
 #include "trace.h"
 #include "exec/log.h"
 #include "qemu.h"
 #include "user-internals.h"
 #include "user-mmap.h"
 #include "target_mman.h"
+#include "qemu/interval-tree.h"
 
 static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER;
 static __thread int mmap_lock_count;
@@ -64,6 +66,44 @@ void mmap_fork_end(int child)
     }
 }
 
+/* Protected by mmap_lock. */
+static IntervalTreeRoot shm_regions;
+
+static void shm_region_add(abi_ptr start, abi_ptr last)
+{
+    IntervalTreeNode *i = g_new0(IntervalTreeNode, 1);
+
+    i->start = start;
+    i->last = last;
+    interval_tree_insert(i, &shm_regions);
+}
+
+static abi_ptr shm_region_find(abi_ptr start)
+{
+    IntervalTreeNode *i;
+
+    for (i = interval_tree_iter_first(&shm_regions, start, start); i;
+         i = interval_tree_iter_next(i, start, start)) {
+        if (i->start == start) {
+            return i->last;
+        }
+    }
+    return 0;
+}
+
+static void shm_region_rm_complete(abi_ptr start, abi_ptr last)
+{
+    IntervalTreeNode *i, *n;
+
+    for (i = interval_tree_iter_first(&shm_regions, start, last); i; i = n) {
+        n = interval_tree_iter_next(i, start, last);
+        if (i->start >= start && i->last <= last) {
+            interval_tree_remove(i, &shm_regions);
+            g_free(i);
+        }
+    }
+}
+
 /*
  * Validate target prot bitmask.
  * Return the prot bitmask for the host in *HOST_PROT.
@@ -720,6 +760,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot,
             page_set_flags(passthrough_last + 1, last, page_flags);
         }
     }
+    shm_region_rm_complete(start, last);
  the_end:
     trace_target_mmap_complete(start);
     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
@@ -817,6 +858,7 @@ int target_munmap(abi_ulong start, abi_ulong len)
     mmap_lock();
     mmap_reserve_or_unmap(start, len);
     page_set_flags(start, start + len - 1, 0);
+    shm_region_rm_complete(start, start + len - 1);
     mmap_unlock();
 
     return 0;
@@ -906,8 +948,10 @@ abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
         new_addr = h2g(host_addr);
         prot = page_get_flags(old_addr);
         page_set_flags(old_addr, old_addr + old_size - 1, 0);
+        shm_region_rm_complete(old_addr, old_addr + old_size - 1);
         page_set_flags(new_addr, new_addr + new_size - 1,
                        prot | PAGE_VALID | PAGE_RESET);
+        shm_region_rm_complete(new_addr, new_addr + new_size - 1);
     }
     mmap_unlock();
     return new_addr;
@@ -981,3 +1025,127 @@ abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice)
 
     return ret;
 }
+
+#ifndef TARGET_FORCE_SHMLBA
+/*
+ * For most architectures, SHMLBA is the same as the page size;
+ * some architectures have larger values, in which case they should
+ * define TARGET_FORCE_SHMLBA and provide a target_shmlba() function.
+ * This corresponds to the kernel arch code defining __ARCH_FORCE_SHMLBA
+ * and defining its own value for SHMLBA.
+ *
+ * The kernel also permits SHMLBA to be set by the architecture to a
+ * value larger than the page size without setting __ARCH_FORCE_SHMLBA;
+ * this means that addresses are rounded to the large size if
+ * SHM_RND is set but addresses not aligned to that size are not rejected
+ * as long as they are at least page-aligned. Since the only architecture
+ * which uses this is ia64 this code doesn't provide for that oddity.
+ */
+static inline abi_ulong target_shmlba(CPUArchState *cpu_env)
+{
+    return TARGET_PAGE_SIZE;
+}
+#endif
+
+abi_ulong target_shmat(CPUArchState *cpu_env, int shmid,
+                       abi_ulong shmaddr, int shmflg)
+{
+    CPUState *cpu = env_cpu(cpu_env);
+    abi_ulong raddr;
+    struct shmid_ds shm_info;
+    int ret;
+    abi_ulong shmlba;
+
+    /* shmat pointers are always untagged */
+
+    /* find out the length of the shared memory segment */
+    ret = get_errno(shmctl(shmid, IPC_STAT, &shm_info));
+    if (is_error(ret)) {
+        /* can't get length, bail out */
+        return ret;
+    }
+
+    shmlba = target_shmlba(cpu_env);
+
+    if (shmaddr & (shmlba - 1)) {
+        if (shmflg & SHM_RND) {
+            shmaddr &= ~(shmlba - 1);
+        } else {
+            return -TARGET_EINVAL;
+        }
+    }
+    if (!guest_range_valid_untagged(shmaddr, shm_info.shm_segsz)) {
+        return -TARGET_EINVAL;
+    }
+
+    WITH_MMAP_LOCK_GUARD() {
+        void *host_raddr;
+        abi_ulong last;
+
+        if (shmaddr) {
+            host_raddr = shmat(shmid, (void *)g2h_untagged(shmaddr), shmflg);
+        } else {
+            abi_ulong mmap_start;
+
+            /* In order to use the host shmat, we need to honor host SHMLBA.  */
+            mmap_start = mmap_find_vma(0, shm_info.shm_segsz,
+                                       MAX(SHMLBA, shmlba));
+
+            if (mmap_start == -1) {
+                return -TARGET_ENOMEM;
+            }
+            host_raddr = shmat(shmid, g2h_untagged(mmap_start),
+                               shmflg | SHM_REMAP);
+        }
+
+        if (host_raddr == (void *)-1) {
+            return get_errno(-1);
+        }
+        raddr = h2g(host_raddr);
+        last = raddr + shm_info.shm_segsz - 1;
+
+        page_set_flags(raddr, last,
+                       PAGE_VALID | PAGE_RESET | PAGE_READ |
+                       (shmflg & SHM_RDONLY ? 0 : PAGE_WRITE));
+
+        shm_region_rm_complete(raddr, last);
+        shm_region_add(raddr, last);
+    }
+
+    /*
+     * We're mapping shared memory, so ensure we generate code for parallel
+     * execution and flush old translations.  This will work up to the level
+     * supported by the host -- anything that requires EXCP_ATOMIC will not
+     * be atomic with respect to an external process.
+     */
+    if (!(cpu->tcg_cflags & CF_PARALLEL)) {
+        cpu->tcg_cflags |= CF_PARALLEL;
+        tb_flush(cpu);
+    }
+
+    return raddr;
+}
+
+abi_long target_shmdt(abi_ulong shmaddr)
+{
+    abi_long rv;
+
+    /* shmdt pointers are always untagged */
+
+    WITH_MMAP_LOCK_GUARD() {
+        abi_ulong last = shm_region_find(shmaddr);
+        if (last == 0) {
+            return -TARGET_EINVAL;
+        }
+
+        rv = get_errno(shmdt(g2h_untagged(shmaddr)));
+        if (rv == 0) {
+            abi_ulong size = last - shmaddr + 1;
+
+            page_set_flags(shmaddr, last, 0);
+            shm_region_rm_complete(shmaddr, last);
+            mmap_reserve_or_unmap(shmaddr, size);
+        }
+    }
+    return rv;
+}
diff --git a/linux-user/nios2/target_proc.h b/linux-user/nios2/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/nios2/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/openrisc/target_proc.h b/linux-user/openrisc/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/openrisc/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/ppc/target_proc.h b/linux-user/ppc/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/ppc/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index 4f8b55e2fb..12f638336a 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -30,7 +30,6 @@ struct image_info {
         abi_ulong       start_data;
         abi_ulong       end_data;
         abi_ulong       brk;
-        abi_ulong       start_mmap;
         abi_ulong       start_stack;
         abi_ulong       stack_limit;
         abi_ulong       entry;
diff --git a/linux-user/riscv/target_proc.h b/linux-user/riscv/target_proc.h
new file mode 100644
index 0000000000..c77c003d65
--- /dev/null
+++ b/linux-user/riscv/target_proc.h
@@ -0,0 +1,37 @@
+/*
+ * RISC-V specific proc functions for linux-user
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef RISCV_TARGET_PROC_H
+#define RISCV_TARGET_PROC_H
+
+static int open_cpuinfo(CPUArchState *cpu_env, int fd)
+{
+    int i;
+    int num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+    RISCVCPU *cpu = env_archcpu(cpu_env);
+    const RISCVCPUConfig *cfg = riscv_cpu_cfg((CPURISCVState *) cpu_env);
+    char *isa_string = riscv_isa_string(cpu);
+    const char *mmu;
+
+    if (cfg->mmu) {
+        mmu = (cpu_env->xl == MXL_RV32) ? "sv32"  : "sv48";
+    } else {
+        mmu = "none";
+    }
+
+    for (i = 0; i < num_cpus; i++) {
+        dprintf(fd, "processor\t: %d\n", i);
+        dprintf(fd, "hart\t\t: %d\n", i);
+        dprintf(fd, "isa\t\t: %s\n", isa_string);
+        dprintf(fd, "mmu\t\t: %s\n", mmu);
+        dprintf(fd, "uarch\t\t: qemu\n\n");
+    }
+
+    g_free(isa_string);
+    return 0;
+}
+#define HAVE_ARCH_PROC_CPUINFO
+
+#endif /* RISCV_TARGET_PROC_H */
diff --git a/linux-user/s390x/target_proc.h b/linux-user/s390x/target_proc.h
new file mode 100644
index 0000000000..a4a4821ea5
--- /dev/null
+++ b/linux-user/s390x/target_proc.h
@@ -0,0 +1,109 @@
+/*
+ * S390X specific proc functions for linux-user
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef S390X_TARGET_PROC_H
+#define S390X_TARGET_PROC_H
+
+/*
+ * Emulate what a Linux kernel running in qemu-system-s390x -M accel=tcg would
+ * show in /proc/cpuinfo.
+ *
+ * Skip the following in order to match the missing support in op_ecag():
+ * - show_cacheinfo().
+ * - show_cpu_topology().
+ * - show_cpu_mhz().
+ *
+ * Use fixed values for certain fields:
+ * - bogomips per cpu - from a qemu-system-s390x run.
+ * - max thread id = 0, since SMT / SIGP_SET_MULTI_THREADING is not supported.
+ *
+ * Keep the code structure close to arch/s390/kernel/processor.c.
+ */
+
+static void show_facilities(int fd)
+{
+    size_t sizeof_stfl_bytes = 2048;
+    g_autofree uint8_t *stfl_bytes = g_new0(uint8_t, sizeof_stfl_bytes);
+    unsigned int bit;
+
+    dprintf(fd, "facilities      :");
+    s390_get_feat_block(S390_FEAT_TYPE_STFL, stfl_bytes);
+    for (bit = 0; bit < sizeof_stfl_bytes * 8; bit++) {
+        if (test_be_bit(bit, stfl_bytes)) {
+            dprintf(fd, " %d", bit);
+        }
+    }
+    dprintf(fd, "\n");
+}
+
+static int cpu_ident(unsigned long n)
+{
+    return deposit32(0, CPU_ID_BITS - CPU_PHYS_ADDR_BITS, CPU_PHYS_ADDR_BITS,
+                     n);
+}
+
+static void show_cpu_summary(CPUArchState *cpu_env, int fd)
+{
+    S390CPUModel *model = env_archcpu(cpu_env)->model;
+    int num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+    uint32_t elf_hwcap = get_elf_hwcap();
+    const char *hwcap_str;
+    int i;
+
+    dprintf(fd, "vendor_id       : IBM/S390\n"
+                "# processors    : %i\n"
+                "bogomips per cpu: 13370.00\n",
+            num_cpus);
+    dprintf(fd, "max thread id   : 0\n");
+    dprintf(fd, "features\t: ");
+    for (i = 0; i < sizeof(elf_hwcap) * 8; i++) {
+        if (!(elf_hwcap & (1 << i))) {
+            continue;
+        }
+        hwcap_str = elf_hwcap_str(i);
+        if (hwcap_str) {
+            dprintf(fd, "%s ", hwcap_str);
+        }
+    }
+    dprintf(fd, "\n");
+    show_facilities(fd);
+    for (i = 0; i < num_cpus; i++) {
+        dprintf(fd, "processor %d: "
+               "version = %02X,  "
+               "identification = %06X,  "
+               "machine = %04X\n",
+               i, model->cpu_ver, cpu_ident(i), model->def->type);
+    }
+}
+
+static void show_cpu_ids(CPUArchState *cpu_env, int fd, unsigned long n)
+{
+    S390CPUModel *model = env_archcpu(cpu_env)->model;
+
+    dprintf(fd, "version         : %02X\n", model->cpu_ver);
+    dprintf(fd, "identification  : %06X\n", cpu_ident(n));
+    dprintf(fd, "machine         : %04X\n", model->def->type);
+}
+
+static void show_cpuinfo(CPUArchState *cpu_env, int fd, unsigned long n)
+{
+    dprintf(fd, "\ncpu number      : %ld\n", n);
+    show_cpu_ids(cpu_env, fd, n);
+}
+
+static int open_cpuinfo(CPUArchState *cpu_env, int fd)
+{
+    int num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+    int i;
+
+    show_cpu_summary(cpu_env, fd);
+    for (i = 0; i < num_cpus; i++) {
+        show_cpuinfo(cpu_env, fd, i);
+    }
+    return 0;
+}
+#define HAVE_ARCH_PROC_CPUINFO
+
+#endif /* S390X_TARGET_PROC_H */
diff --git a/linux-user/sh4/target_proc.h b/linux-user/sh4/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/sh4/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/sparc/target_proc.h b/linux-user/sparc/target_proc.h
new file mode 100644
index 0000000000..3bb3134a47
--- /dev/null
+++ b/linux-user/sparc/target_proc.h
@@ -0,0 +1,16 @@
+/*
+ * Sparc specific proc functions for linux-user
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef SPARC_TARGET_PROC_H
+#define SPARC_TARGET_PROC_H
+
+static int open_cpuinfo(CPUArchState *cpu_env, int fd)
+{
+    dprintf(fd, "type\t\t: sun4u\n");
+    return 0;
+}
+#define HAVE_ARCH_PROC_CPUINFO
+
+#endif /* SPARC_TARGET_PROC_H */
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 7ccd3affbe..dac0641bab 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3725,14 +3725,6 @@ static abi_long do_socketcall(int num, abi_ulong vptr)
 }
 #endif
 
-#define N_SHM_REGIONS	32
-
-static struct shm_region {
-    abi_ulong start;
-    abi_ulong size;
-    bool in_use;
-} shm_regions[N_SHM_REGIONS];
-
 #ifndef TARGET_SEMID64_DS
 /* asm-generic version of this struct */
 struct target_semid64_ds
@@ -4482,133 +4474,6 @@ static inline abi_long do_shmctl(int shmid, int cmd, abi_long buf)
     return ret;
 }
 
-#ifndef TARGET_FORCE_SHMLBA
-/* For most architectures, SHMLBA is the same as the page size;
- * some architectures have larger values, in which case they should
- * define TARGET_FORCE_SHMLBA and provide a target_shmlba() function.
- * This corresponds to the kernel arch code defining __ARCH_FORCE_SHMLBA
- * and defining its own value for SHMLBA.
- *
- * The kernel also permits SHMLBA to be set by the architecture to a
- * value larger than the page size without setting __ARCH_FORCE_SHMLBA;
- * this means that addresses are rounded to the large size if
- * SHM_RND is set but addresses not aligned to that size are not rejected
- * as long as they are at least page-aligned. Since the only architecture
- * which uses this is ia64 this code doesn't provide for that oddity.
- */
-static inline abi_ulong target_shmlba(CPUArchState *cpu_env)
-{
-    return TARGET_PAGE_SIZE;
-}
-#endif
-
-static abi_ulong do_shmat(CPUArchState *cpu_env, int shmid,
-                          abi_ulong shmaddr, int shmflg)
-{
-    CPUState *cpu = env_cpu(cpu_env);
-    abi_ulong raddr;
-    void *host_raddr;
-    struct shmid_ds shm_info;
-    int i, ret;
-    abi_ulong shmlba;
-
-    /* shmat pointers are always untagged */
-
-    /* find out the length of the shared memory segment */
-    ret = get_errno(shmctl(shmid, IPC_STAT, &shm_info));
-    if (is_error(ret)) {
-        /* can't get length, bail out */
-        return ret;
-    }
-
-    shmlba = target_shmlba(cpu_env);
-
-    if (shmaddr & (shmlba - 1)) {
-        if (shmflg & SHM_RND) {
-            shmaddr &= ~(shmlba - 1);
-        } else {
-            return -TARGET_EINVAL;
-        }
-    }
-    if (!guest_range_valid_untagged(shmaddr, shm_info.shm_segsz)) {
-        return -TARGET_EINVAL;
-    }
-
-    mmap_lock();
-
-    /*
-     * We're mapping shared memory, so ensure we generate code for parallel
-     * execution and flush old translations.  This will work up to the level
-     * supported by the host -- anything that requires EXCP_ATOMIC will not
-     * be atomic with respect to an external process.
-     */
-    if (!(cpu->tcg_cflags & CF_PARALLEL)) {
-        cpu->tcg_cflags |= CF_PARALLEL;
-        tb_flush(cpu);
-    }
-
-    if (shmaddr)
-        host_raddr = shmat(shmid, (void *)g2h_untagged(shmaddr), shmflg);
-    else {
-        abi_ulong mmap_start;
-
-        /* In order to use the host shmat, we need to honor host SHMLBA.  */
-        mmap_start = mmap_find_vma(0, shm_info.shm_segsz, MAX(SHMLBA, shmlba));
-
-        if (mmap_start == -1) {
-            errno = ENOMEM;
-            host_raddr = (void *)-1;
-        } else
-            host_raddr = shmat(shmid, g2h_untagged(mmap_start),
-                               shmflg | SHM_REMAP);
-    }
-
-    if (host_raddr == (void *)-1) {
-        mmap_unlock();
-        return get_errno((intptr_t)host_raddr);
-    }
-    raddr = h2g((uintptr_t)host_raddr);
-
-    page_set_flags(raddr, raddr + shm_info.shm_segsz - 1,
-                   PAGE_VALID | PAGE_RESET | PAGE_READ |
-                   (shmflg & SHM_RDONLY ? 0 : PAGE_WRITE));
-
-    for (i = 0; i < N_SHM_REGIONS; i++) {
-        if (!shm_regions[i].in_use) {
-            shm_regions[i].in_use = true;
-            shm_regions[i].start = raddr;
-            shm_regions[i].size = shm_info.shm_segsz;
-            break;
-        }
-    }
-
-    mmap_unlock();
-    return raddr;
-}
-
-static inline abi_long do_shmdt(abi_ulong shmaddr)
-{
-    int i;
-    abi_long rv;
-
-    /* shmdt pointers are always untagged */
-
-    mmap_lock();
-
-    for (i = 0; i < N_SHM_REGIONS; ++i) {
-        if (shm_regions[i].in_use && shm_regions[i].start == shmaddr) {
-            shm_regions[i].in_use = false;
-            page_set_flags(shmaddr, shmaddr + shm_regions[i].size - 1, 0);
-            break;
-        }
-    }
-    rv = get_errno(shmdt(g2h_untagged(shmaddr)));
-
-    mmap_unlock();
-
-    return rv;
-}
-
 #ifdef TARGET_NR_ipc
 /* ??? This only works with linear mappings.  */
 /* do_ipc() must return target values and target errnos. */
@@ -4695,7 +4560,7 @@ static abi_long do_ipc(CPUArchState *cpu_env,
         default:
         {
             abi_ulong raddr;
-            raddr = do_shmat(cpu_env, first, ptr, second);
+            raddr = target_shmat(cpu_env, first, ptr, second);
             if (is_error(raddr))
                 return get_errno(raddr);
             if (put_user_ual(raddr, third))
@@ -4708,7 +4573,7 @@ static abi_long do_ipc(CPUArchState *cpu_env,
         }
 	break;
     case IPCOP_shmdt:
-        ret = do_shmdt(ptr);
+        ret = target_shmdt(ptr);
 	break;
 
     case IPCOP_shmget:
@@ -8095,12 +7960,68 @@ static int open_self_cmdline(CPUArchState *cpu_env, int fd)
     return 0;
 }
 
-static void show_smaps(int fd, unsigned long size)
+struct open_self_maps_data {
+    TaskState *ts;
+    IntervalTreeRoot *host_maps;
+    int fd;
+    bool smaps;
+};
+
+/*
+ * Subroutine to output one line of /proc/self/maps,
+ * or one region of /proc/self/smaps.
+ */
+
+#ifdef TARGET_HPPA
+# define test_stack(S, E, L)  (E == L)
+#else
+# define test_stack(S, E, L)  (S == L)
+#endif
+
+static void open_self_maps_4(const struct open_self_maps_data *d,
+                             const MapInfo *mi, abi_ptr start,
+                             abi_ptr end, unsigned flags)
 {
-    unsigned long page_size_kb = TARGET_PAGE_SIZE >> 10;
-    unsigned long size_kb = size >> 10;
+    const struct image_info *info = d->ts->info;
+    const char *path = mi->path;
+    uint64_t offset;
+    int fd = d->fd;
+    int count;
+
+    if (test_stack(start, end, info->stack_limit)) {
+        path = "[stack]";
+    } else if (start == info->brk) {
+        path = "[heap]";
+    }
+
+    /* Except null device (MAP_ANON), adjust offset for this fragment. */
+    offset = mi->offset;
+    if (mi->dev) {
+        uintptr_t hstart = (uintptr_t)g2h_untagged(start);
+        offset += hstart - mi->itree.start;
+    }
+
+    count = dprintf(fd, TARGET_ABI_FMT_ptr "-" TARGET_ABI_FMT_ptr
+                    " %c%c%c%c %08" PRIx64 " %02x:%02x %"PRId64,
+                    start, end,
+                    (flags & PAGE_READ) ? 'r' : '-',
+                    (flags & PAGE_WRITE_ORG) ? 'w' : '-',
+                    (flags & PAGE_EXEC) ? 'x' : '-',
+                    mi->is_priv ? 'p' : 's',
+                    offset, major(mi->dev), minor(mi->dev),
+                    (uint64_t)mi->inode);
+    if (path) {
+        dprintf(fd, "%*s%s\n", 73 - count, "", path);
+    } else {
+        dprintf(fd, "\n");
+    }
+
+    if (d->smaps) {
+        unsigned long size = end - start;
+        unsigned long page_size_kb = TARGET_PAGE_SIZE >> 10;
+        unsigned long size_kb = size >> 10;
 
-    dprintf(fd, "Size:                  %lu kB\n"
+        dprintf(fd, "Size:                  %lu kB\n"
                 "KernelPageSize:        %lu kB\n"
                 "MMUPageSize:           %lu kB\n"
                 "Rss:                   0 kB\n"
@@ -8111,7 +8032,7 @@ static void show_smaps(int fd, unsigned long size)
                 "Private_Clean:         0 kB\n"
                 "Private_Dirty:         0 kB\n"
                 "Referenced:            0 kB\n"
-                "Anonymous:             0 kB\n"
+                "Anonymous:             %lu kB\n"
                 "LazyFree:              0 kB\n"
                 "AnonHugePages:         0 kB\n"
                 "ShmemPmdMapped:        0 kB\n"
@@ -8121,89 +8042,76 @@ static void show_smaps(int fd, unsigned long size)
                 "Swap:                  0 kB\n"
                 "SwapPss:               0 kB\n"
                 "Locked:                0 kB\n"
-                "THPeligible:    0\n", size_kb, page_size_kb, page_size_kb);
+                "THPeligible:    0\n"
+                "VmFlags:%s%s%s%s%s%s%s%s\n",
+                size_kb, page_size_kb, page_size_kb,
+                (flags & PAGE_ANON ? size_kb : 0),
+                (flags & PAGE_READ) ? " rd" : "",
+                (flags & PAGE_WRITE_ORG) ? " wr" : "",
+                (flags & PAGE_EXEC) ? " ex" : "",
+                mi->is_priv ? "" : " sh",
+                (flags & PAGE_READ) ? " mr" : "",
+                (flags & PAGE_WRITE_ORG) ? " mw" : "",
+                (flags & PAGE_EXEC) ? " me" : "",
+                mi->is_priv ? "" : " ms");
+    }
 }
 
-static int open_self_maps_1(CPUArchState *cpu_env, int fd, bool smaps)
+/*
+ * Callback for walk_memory_regions, when read_self_maps() fails.
+ * Proceed without the benefit of host /proc/self/maps cross-check.
+ */
+static int open_self_maps_3(void *opaque, target_ulong guest_start,
+                            target_ulong guest_end, unsigned long flags)
 {
-    CPUState *cpu = env_cpu(cpu_env);
-    TaskState *ts = cpu->opaque;
-    IntervalTreeRoot *map_info = read_self_maps();
-    IntervalTreeNode *s;
-    int count;
+    static const MapInfo mi = { .is_priv = true };
 
-    for (s = interval_tree_iter_first(map_info, 0, -1); s;
-         s = interval_tree_iter_next(s, 0, -1)) {
-        MapInfo *e = container_of(s, MapInfo, itree);
+    open_self_maps_4(opaque, &mi, guest_start, guest_end, flags);
+    return 0;
+}
 
-        if (h2g_valid(e->itree.start)) {
-            unsigned long min = e->itree.start;
-            unsigned long max = e->itree.last + 1;
-            int flags = page_get_flags(h2g(min));
-            const char *path;
+/*
+ * Callback for walk_memory_regions, when read_self_maps() succeeds.
+ */
+static int open_self_maps_2(void *opaque, target_ulong guest_start,
+                            target_ulong guest_end, unsigned long flags)
+{
+    const struct open_self_maps_data *d = opaque;
+    uintptr_t host_start = (uintptr_t)g2h_untagged(guest_start);
+    uintptr_t host_last = (uintptr_t)g2h_untagged(guest_end - 1);
 
-            max = h2g_valid(max - 1) ?
-                max : (uintptr_t) g2h_untagged(GUEST_ADDR_MAX) + 1;
+    while (1) {
+        IntervalTreeNode *n =
+            interval_tree_iter_first(d->host_maps, host_start, host_start);
+        MapInfo *mi = container_of(n, MapInfo, itree);
+        uintptr_t this_hlast = MIN(host_last, n->last);
+        target_ulong this_gend = h2g(this_hlast) + 1;
 
-            if (!page_check_range(h2g(min), max - min, flags)) {
-                continue;
-            }
+        open_self_maps_4(d, mi, guest_start, this_gend, flags);
 
-#ifdef TARGET_HPPA
-            if (h2g(max) == ts->info->stack_limit) {
-#else
-            if (h2g(min) == ts->info->stack_limit) {
-#endif
-                path = "[stack]";
-            } else {
-                path = e->path;
-            }
-
-            count = dprintf(fd, TARGET_ABI_FMT_ptr "-" TARGET_ABI_FMT_ptr
-                            " %c%c%c%c %08" PRIx64 " %s %"PRId64,
-                            h2g(min), h2g(max - 1) + 1,
-                            (flags & PAGE_READ) ? 'r' : '-',
-                            (flags & PAGE_WRITE_ORG) ? 'w' : '-',
-                            (flags & PAGE_EXEC) ? 'x' : '-',
-                            e->is_priv ? 'p' : 's',
-                            (uint64_t) e->offset, e->dev, e->inode);
-            if (path) {
-                dprintf(fd, "%*s%s\n", 73 - count, "", path);
-            } else {
-                dprintf(fd, "\n");
-            }
-            if (smaps) {
-                show_smaps(fd, max - min);
-                dprintf(fd, "VmFlags:%s%s%s%s%s%s%s%s\n",
-                        (flags & PAGE_READ) ? " rd" : "",
-                        (flags & PAGE_WRITE_ORG) ? " wr" : "",
-                        (flags & PAGE_EXEC) ? " ex" : "",
-                        e->is_priv ? "" : " sh",
-                        (flags & PAGE_READ) ? " mr" : "",
-                        (flags & PAGE_WRITE_ORG) ? " mw" : "",
-                        (flags & PAGE_EXEC) ? " me" : "",
-                        e->is_priv ? "" : " ms");
-            }
+        if (this_hlast == host_last) {
+            return 0;
         }
+        host_start = this_hlast + 1;
+        guest_start = h2g(host_start);
     }
+}
 
-    free_self_maps(map_info);
+static int open_self_maps_1(CPUArchState *env, int fd, bool smaps)
+{
+    struct open_self_maps_data d = {
+        .ts = env_cpu(env)->opaque,
+        .host_maps = read_self_maps(),
+        .fd = fd,
+        .smaps = smaps
+    };
 
-#ifdef TARGET_VSYSCALL_PAGE
-    /*
-     * We only support execution from the vsyscall page.
-     * This is as if CONFIG_LEGACY_VSYSCALL_XONLY=y from v5.3.
-     */
-    count = dprintf(fd, TARGET_FMT_lx "-" TARGET_FMT_lx
-                    " --xp 00000000 00:00 0",
-                    TARGET_VSYSCALL_PAGE, TARGET_VSYSCALL_PAGE + TARGET_PAGE_SIZE);
-    dprintf(fd, "%*s%s\n", 73 - count, "",  "[vsyscall]");
-    if (smaps) {
-        show_smaps(fd, TARGET_PAGE_SIZE);
-        dprintf(fd, "VmFlags: ex\n");
+    if (d.host_maps) {
+        walk_memory_regions(&d, open_self_maps_2);
+        free_self_maps(d.host_maps);
+    } else {
+        walk_memory_regions(&d, open_self_maps_3);
     }
-#endif
-
     return 0;
 }
 
@@ -8339,9 +8247,11 @@ void target_exception_dump(CPUArchState *env, const char *fmt, int code)
     }
 }
 
+#include "target_proc.h"
+
 #if HOST_BIG_ENDIAN != TARGET_BIG_ENDIAN || \
-    defined(TARGET_SPARC) || defined(TARGET_M68K) || defined(TARGET_HPPA) || \
-    defined(TARGET_RISCV) || defined(TARGET_S390X)
+    defined(HAVE_ARCH_PROC_CPUINFO) || \
+    defined(HAVE_ARCH_PROC_HARDWARE)
 static int is_proc(const char *filename, const char *entry)
 {
     return strcmp(filename, entry) == 0;
@@ -8393,171 +8303,6 @@ static int open_net_route(CPUArchState *cpu_env, int fd)
 }
 #endif
 
-#if defined(TARGET_SPARC)
-static int open_cpuinfo(CPUArchState *cpu_env, int fd)
-{
-    dprintf(fd, "type\t\t: sun4u\n");
-    return 0;
-}
-#endif
-
-#if defined(TARGET_HPPA)
-static int open_cpuinfo(CPUArchState *cpu_env, int fd)
-{
-    int i, num_cpus;
-
-    num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
-    for (i = 0; i < num_cpus; i++) {
-        dprintf(fd, "processor\t: %d\n", i);
-        dprintf(fd, "cpu family\t: PA-RISC 1.1e\n");
-        dprintf(fd, "cpu\t\t: PA7300LC (PCX-L2)\n");
-        dprintf(fd, "capabilities\t: os32\n");
-        dprintf(fd, "model\t\t: 9000/778/B160L - "
-                    "Merlin L2 160 QEMU (9000/778/B160L)\n\n");
-    }
-    return 0;
-}
-#endif
-
-#if defined(TARGET_RISCV)
-static int open_cpuinfo(CPUArchState *cpu_env, int fd)
-{
-    int i;
-    int num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
-    RISCVCPU *cpu = env_archcpu(cpu_env);
-    const RISCVCPUConfig *cfg = riscv_cpu_cfg((CPURISCVState *) cpu_env);
-    char *isa_string = riscv_isa_string(cpu);
-    const char *mmu;
-
-    if (cfg->mmu) {
-        mmu = (cpu_env->xl == MXL_RV32) ? "sv32"  : "sv48";
-    } else {
-        mmu = "none";
-    }
-
-    for (i = 0; i < num_cpus; i++) {
-        dprintf(fd, "processor\t: %d\n", i);
-        dprintf(fd, "hart\t\t: %d\n", i);
-        dprintf(fd, "isa\t\t: %s\n", isa_string);
-        dprintf(fd, "mmu\t\t: %s\n", mmu);
-        dprintf(fd, "uarch\t\t: qemu\n\n");
-    }
-
-    g_free(isa_string);
-    return 0;
-}
-#endif
-
-#if defined(TARGET_S390X)
-/*
- * Emulate what a Linux kernel running in qemu-system-s390x -M accel=tcg would
- * show in /proc/cpuinfo.
- *
- * Skip the following in order to match the missing support in op_ecag():
- * - show_cacheinfo().
- * - show_cpu_topology().
- * - show_cpu_mhz().
- *
- * Use fixed values for certain fields:
- * - bogomips per cpu - from a qemu-system-s390x run.
- * - max thread id = 0, since SMT / SIGP_SET_MULTI_THREADING is not supported.
- *
- * Keep the code structure close to arch/s390/kernel/processor.c.
- */
-
-static void show_facilities(int fd)
-{
-    size_t sizeof_stfl_bytes = 2048;
-    g_autofree uint8_t *stfl_bytes = g_new0(uint8_t, sizeof_stfl_bytes);
-    unsigned int bit;
-
-    dprintf(fd, "facilities      :");
-    s390_get_feat_block(S390_FEAT_TYPE_STFL, stfl_bytes);
-    for (bit = 0; bit < sizeof_stfl_bytes * 8; bit++) {
-        if (test_be_bit(bit, stfl_bytes)) {
-            dprintf(fd, " %d", bit);
-        }
-    }
-    dprintf(fd, "\n");
-}
-
-static int cpu_ident(unsigned long n)
-{
-    return deposit32(0, CPU_ID_BITS - CPU_PHYS_ADDR_BITS, CPU_PHYS_ADDR_BITS,
-                     n);
-}
-
-static void show_cpu_summary(CPUArchState *cpu_env, int fd)
-{
-    S390CPUModel *model = env_archcpu(cpu_env)->model;
-    int num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
-    uint32_t elf_hwcap = get_elf_hwcap();
-    const char *hwcap_str;
-    int i;
-
-    dprintf(fd, "vendor_id       : IBM/S390\n"
-                "# processors    : %i\n"
-                "bogomips per cpu: 13370.00\n",
-            num_cpus);
-    dprintf(fd, "max thread id   : 0\n");
-    dprintf(fd, "features\t: ");
-    for (i = 0; i < sizeof(elf_hwcap) * 8; i++) {
-        if (!(elf_hwcap & (1 << i))) {
-            continue;
-        }
-        hwcap_str = elf_hwcap_str(i);
-        if (hwcap_str) {
-            dprintf(fd, "%s ", hwcap_str);
-        }
-    }
-    dprintf(fd, "\n");
-    show_facilities(fd);
-    for (i = 0; i < num_cpus; i++) {
-        dprintf(fd, "processor %d: "
-               "version = %02X,  "
-               "identification = %06X,  "
-               "machine = %04X\n",
-               i, model->cpu_ver, cpu_ident(i), model->def->type);
-    }
-}
-
-static void show_cpu_ids(CPUArchState *cpu_env, int fd, unsigned long n)
-{
-    S390CPUModel *model = env_archcpu(cpu_env)->model;
-
-    dprintf(fd, "version         : %02X\n", model->cpu_ver);
-    dprintf(fd, "identification  : %06X\n", cpu_ident(n));
-    dprintf(fd, "machine         : %04X\n", model->def->type);
-}
-
-static void show_cpuinfo(CPUArchState *cpu_env, int fd, unsigned long n)
-{
-    dprintf(fd, "\ncpu number      : %ld\n", n);
-    show_cpu_ids(cpu_env, fd, n);
-}
-
-static int open_cpuinfo(CPUArchState *cpu_env, int fd)
-{
-    int num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
-    int i;
-
-    show_cpu_summary(cpu_env, fd);
-    for (i = 0; i < num_cpus; i++) {
-        show_cpuinfo(cpu_env, fd, i);
-    }
-    return 0;
-}
-#endif
-
-#if defined(TARGET_M68K)
-static int open_hardware(CPUArchState *cpu_env, int fd)
-{
-    dprintf(fd, "Model:\t\tqemu-m68k\n");
-    return 0;
-}
-#endif
-
-
 int do_guest_openat(CPUArchState *cpu_env, int dirfd, const char *fname,
                     int flags, mode_t mode, bool safe)
 {
@@ -8578,11 +8323,10 @@ int do_guest_openat(CPUArchState *cpu_env, int dirfd, const char *fname,
 #if HOST_BIG_ENDIAN != TARGET_BIG_ENDIAN
         { "/proc/net/route", open_net_route, is_proc },
 #endif
-#if defined(TARGET_SPARC) || defined(TARGET_HPPA) || \
-    defined(TARGET_RISCV) || defined(TARGET_S390X)
+#if defined(HAVE_ARCH_PROC_CPUINFO)
         { "/proc/cpuinfo", open_cpuinfo, is_proc },
 #endif
-#if defined(TARGET_M68K)
+#if defined(HAVE_ARCH_PROC_HARDWARE)
         { "/proc/hardware", open_hardware, is_proc },
 #endif
         { NULL, NULL, NULL }
@@ -11129,11 +10873,11 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int num, abi_long arg1,
 #endif
 #ifdef TARGET_NR_shmat
     case TARGET_NR_shmat:
-        return do_shmat(cpu_env, arg1, arg2, arg3);
+        return target_shmat(cpu_env, arg1, arg2, arg3);
 #endif
 #ifdef TARGET_NR_shmdt
     case TARGET_NR_shmdt:
-        return do_shmdt(arg1);
+        return target_shmdt(arg1);
 #endif
     case TARGET_NR_fsync:
         return get_errno(fsync(arg1));
diff --git a/linux-user/user-mmap.h b/linux-user/user-mmap.h
index 0f4883eb57..b94bcdcf83 100644
--- a/linux-user/user-mmap.h
+++ b/linux-user/user-mmap.h
@@ -58,4 +58,8 @@ abi_ulong mmap_find_vma(abi_ulong, abi_ulong, abi_ulong);
 void mmap_fork_start(void);
 void mmap_fork_end(int child);
 
+abi_ulong target_shmat(CPUArchState *cpu_env, int shmid,
+                       abi_ulong shmaddr, int shmflg);
+abi_long target_shmdt(abi_ulong shmaddr);
+
 #endif /* LINUX_USER_USER_MMAP_H */
diff --git a/linux-user/x86_64/target_proc.h b/linux-user/x86_64/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/x86_64/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */
diff --git a/linux-user/xtensa/target_proc.h b/linux-user/xtensa/target_proc.h
new file mode 100644
index 0000000000..43fe29ca72
--- /dev/null
+++ b/linux-user/xtensa/target_proc.h
@@ -0,0 +1 @@
+/* No target-specific /proc support */