diff --git a/src/coreclr/jit/morph.cpp b/src/coreclr/jit/morph.cpp
index cb04806feebbb..af23a79476f75 100644
--- a/src/coreclr/jit/morph.cpp
+++ b/src/coreclr/jit/morph.cpp
@@ -12748,6 +12748,8 @@ GenTree* Compiler::fgMorphSmpOp(GenTree* tree, MorphAddrContext* mac)
 
         CM_ADD_OP:
 
+            FALLTHROUGH;
+
         case GT_OR:
         case GT_XOR:
         case GT_AND:
diff --git a/src/coreclr/minipal/Unix/doublemapping.cpp b/src/coreclr/minipal/Unix/doublemapping.cpp
index 6e0278e3ccd69..3772c46153919 100644
--- a/src/coreclr/minipal/Unix/doublemapping.cpp
+++ b/src/coreclr/minipal/Unix/doublemapping.cpp
@@ -41,6 +41,12 @@ bool VMToOSInterface::CreateDoubleMemoryMapper(void** pHandle, size_t *pMaxExecu
 
 #ifdef TARGET_FREEBSD
     int fd = shm_open(SHM_ANON, O_RDWR | O_CREAT, S_IRWXU);
+#elif defined(TARGET_SUNOS) // has POSIX implementation
+    char name[24];
+    sprintf(name, "/shm-dotnet-%d", getpid());
+    name[sizeof(name) - 1] = '\0';
+    shm_unlink(name);
+    int fd = shm_open(name, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW, 0600);
 #else // TARGET_FREEBSD
     int fd = memfd_create("doublemapper", MFD_CLOEXEC);
 #endif // TARGET_FREEBSD
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.MountPoints.FormatInfo.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.MountPoints.FormatInfo.cs
index 05d74c84e789d..15d6aa3c2f147 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.MountPoints.FormatInfo.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.MountPoints.FormatInfo.cs
@@ -165,6 +165,7 @@ private static DriveType GetDriveType(string fileSystemName)
                 case "qnx6":
                 case "reiserfs":
                 case "rpc_pipefs":
+                case "sffs":
                 case "smackfs":
                 case "squashfs":
                 case "swap":
@@ -179,6 +180,8 @@ private static DriveType GetDriveType(string fileSystemName)
                 case "umsdos":
                 case "umview-mod-umfuseext2":
                 case "v9fs":
+                case "vagrant":
+                case "vboxfs":
                 case "vxfs":
                 case "vxfs_olt":
                 case "vzfs":
@@ -304,6 +307,7 @@ private static DriveType GetDriveType(string fileSystemName)
                 case "sockfs":
                 case "sysfs":
                 case "tmpfs":
+                case "udev":
                 case "usbdev":
                 case "usbdevfs":
                     return DriveType.Ram;
@@ -314,8 +318,8 @@ private static DriveType GetDriveType(string fileSystemName)
                 case "vfat":
                     return DriveType.Removable;
 
-                    // Categorize as "Unknown" everything else not explicitly
-                    // recognized as a particular drive type.
+                // Categorize as "Unknown" everything else not explicitly
+                // recognized as a particular drive type.
                 default:
                     return DriveType.Unknown;
             }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.UnixFileSystemTypes.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.UnixFileSystemTypes.cs
index fd34f87418223..892e5ccaaed33 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.UnixFileSystemTypes.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.UnixFileSystemTypes.cs
@@ -38,8 +38,11 @@ internal enum UnixFileSystemTypes : long
             coda = 0x73757245,
             coherent = 0x012FF7B7,
             configfs = 0x62656570,
+            cpuset = 0x01021994, // same as tmpfs
             cramfs = 0x28CD3D45,
+            ctfs = 0x01021994, // same as tmpfs
             debugfs = 0x64626720,
+            dev = 0x1373, // same as devfs
             devfs = 0x1373,
             devpts = 0x1CD1,
             ecryptfs = 0xF15F,
@@ -81,6 +84,7 @@ internal enum UnixFileSystemTypes : long
             minix2 = 0x2468, /* minix V2 */
             minix2v2 = 0x2478, /* MINIX V2, 30 char names */
             minix3 = 0x4D5A,
+            mntfs = 0x01021994, // same as tmpfs
             mqueue = 0x19800202,
             msdos = 0x4D44,
             nfs = 0x6969,
@@ -88,8 +92,9 @@ internal enum UnixFileSystemTypes : long
             nilfs = 0x3434,
             novell = 0x564C,
             ntfs = 0x5346544E,
-            openprom = 0x9FA1,
+            objfs = 0x01021994, // same as tmpfs
             ocfs2 = 0x7461636F,
+            openprom = 0x9FA1,
             omfs = 0xC2993D87,
             overlay = 0x794C7630,
             overlayfs = 0x794C764F,
@@ -107,6 +112,8 @@ internal enum UnixFileSystemTypes : long
             samba = 0x517B,
             securityfs = 0x73636673,
             selinux = 0xF97CFF8C,
+            sffs = 0x786F4256, // same as vboxfs
+            sharefs = 0x01021994, // same as tmpfs
             smb = 0x517B,
             smb2 = 0xFE534D42,
             sockfs = 0x534F434B,
@@ -122,6 +129,8 @@ internal enum UnixFileSystemTypes : long
             ufs2 = 0x19540119,
             usbdevice = 0x9FA2,
             v9fs = 0x01021997,
+            vagrant = 0x786F4256, // same as vboxfs
+            vboxfs = 0x786F4256,
             vmhgfs = 0xBACBACBC,
             vxfs = 0xA501FCF5,
             vzfs = 0x565A4653,
@@ -129,6 +138,7 @@ internal enum UnixFileSystemTypes : long
             xenix = 0x012FF7B4,
             xfs = 0x58465342,
             xia = 0x012FD16D,
+            udev = 0x01021994, // same as tmpfs
             zfs = 0x2FC12FC1,
         }
 
diff --git a/src/libraries/Native/Unix/CMakeLists.txt b/src/libraries/Native/Unix/CMakeLists.txt
index fcd7964aacbe8..31cea57a62938 100644
--- a/src/libraries/Native/Unix/CMakeLists.txt
+++ b/src/libraries/Native/Unix/CMakeLists.txt
@@ -235,7 +235,7 @@ if(CLR_CMAKE_TARGET_UNIX)
         else()
             add_compile_options($<$<COMPILE_LANGUAGE:ASM>:-Wa,--noexecstack>)
             if(CLR_CMAKE_TARGET_SUNOS)
-                add_definitions(-D__EXTENSIONS__ -D_XPG4_2 -D_POSIX_PTHREAD_SEMANTICS)
+                add_definitions(-D__EXTENSIONS__ -D_XPG4_2 -D_POSIX_PTHREAD_SEMANTICS -DTARGET_SUNOS)
             else()
                 # -z,now is required for full relro.
                 # see https://www.redhat.com/en/blog/hardening-elf-binaries-using-relocation-read-only-relro
diff --git a/src/libraries/Native/Unix/System.Native/pal_io.c b/src/libraries/Native/Unix/System.Native/pal_io.c
index 6534265085639..51d841ffc55bd 100644
--- a/src/libraries/Native/Unix/System.Native/pal_io.c
+++ b/src/libraries/Native/Unix/System.Native/pal_io.c
@@ -39,6 +39,10 @@
 #include <sys/vfs.h>
 #elif HAVE_STATFS_MOUNT // BSD
 #include <sys/mount.h>
+#elif !HAVE_NON_LEGACY_STATFS // SunOS
+#include <sys/types.h>
+#include <sys/statvfs.h>
+#include <sys/vfs.h>
 #endif
 
 #ifdef _AIX
@@ -46,7 +50,7 @@
 // Somehow, AIX mangles the definition for this behind a C++ def
 // Redeclare it here
 extern int     getpeereid(int, uid_t *__restrict__, gid_t *__restrict__);
-#elif defined(__sun)
+#elif defined(TARGET_SUNOS)
 #ifndef _KERNEL
 #define _KERNEL
 #define UNDEF_KERNEL
@@ -1405,8 +1409,139 @@ int64_t SystemNative_GetFileSystemType(intptr_t fd)
     // which got deprecated in macOS 10.6, in favor of statfs
     while ((statfsRes = fstatfs(ToFileDescriptor(fd), &statfsArgs)) == -1 && errno == EINTR) ;
     return statfsRes == -1 ? (int64_t)-1 : (int64_t)statfsArgs.f_type;
+#elif !HAVE_NON_LEGACY_STATFS
+    int statfsRes;
+    struct statvfs statfsArgs;
+    while ((statfsRes = fstatvfs(ToFileDescriptor(fd), &statfsArgs)) == -1 && errno == EINTR) ;
+    if (statfsRes == -1) return (int64_t)-1;
+
+    int64_t result = -1;
+
+    if (strcmp(statfsArgs.f_basetype, "adfs") == 0) result = 0xADF5;
+    else if (strcmp(statfsArgs.f_basetype, "affs") == 0) result = 0xADFF;
+    else if (strcmp(statfsArgs.f_basetype, "afs") == 0) result = 0x5346414F;
+    else if (strcmp(statfsArgs.f_basetype, "anoninode") == 0) result = 0x09041934;
+    else if (strcmp(statfsArgs.f_basetype, "aufs") == 0) result = 0x61756673;
+    else if (strcmp(statfsArgs.f_basetype, "autofs") == 0) result = 0x0187;
+    else if (strcmp(statfsArgs.f_basetype, "autofs4") == 0) result = 0x6D4A556D;
+    else if (strcmp(statfsArgs.f_basetype, "befs") == 0) result = 0x42465331;
+    else if (strcmp(statfsArgs.f_basetype, "bdevfs") == 0) result = 0x62646576;
+    else if (strcmp(statfsArgs.f_basetype, "bfs") == 0) result = 0x1BADFACE;
+    else if (strcmp(statfsArgs.f_basetype, "binfmt_misc") == 0) result = 0x42494E4D;
+    else if (strcmp(statfsArgs.f_basetype, "bootfs") == 0) result = 0xA56D3FF9;
+    else if (strcmp(statfsArgs.f_basetype, "btrfs") == 0) result = 0x9123683E;
+    else if (strcmp(statfsArgs.f_basetype, "ceph") == 0) result = 0x00C36400;
+    else if (strcmp(statfsArgs.f_basetype, "cgroupfs") == 0) result = 0x0027E0EB;
+    else if (strcmp(statfsArgs.f_basetype, "cgroup2fs") == 0) result = 0x63677270;
+    else if (strcmp(statfsArgs.f_basetype, "cifs") == 0) result = 0xFF534D42;
+    else if (strcmp(statfsArgs.f_basetype, "coda") == 0) result = 0x73757245;
+    else if (strcmp(statfsArgs.f_basetype, "coherent") == 0) result = 0x012FF7B7;
+    else if (strcmp(statfsArgs.f_basetype, "configfs") == 0) result = 0x62656570;
+    else if (strcmp(statfsArgs.f_basetype, "cpuset") == 0) result = 0x01021994;
+    else if (strcmp(statfsArgs.f_basetype, "cramfs") == 0) result = 0x28CD3D45;
+    else if (strcmp(statfsArgs.f_basetype, "ctfs") == 0) result = 0x01021994;
+    else if (strcmp(statfsArgs.f_basetype, "debugfs") == 0) result = 0x64626720;
+    else if (strcmp(statfsArgs.f_basetype, "dev") == 0) result = 0x1373;
+    else if (strcmp(statfsArgs.f_basetype, "devfs") == 0) result = 0x1373;
+    else if (strcmp(statfsArgs.f_basetype, "devpts") == 0) result = 0x1CD1;
+    else if (strcmp(statfsArgs.f_basetype, "ecryptfs") == 0) result = 0xF15F;
+    else if (strcmp(statfsArgs.f_basetype, "efs") == 0) result = 0x00414A53;
+    else if (strcmp(statfsArgs.f_basetype, "exofs") == 0) result = 0x5DF5;
+    else if (strcmp(statfsArgs.f_basetype, "ext") == 0) result = 0x137D;
+    else if (strcmp(statfsArgs.f_basetype, "ext2_old") == 0) result = 0xEF51;
+    else if (strcmp(statfsArgs.f_basetype, "ext2") == 0) result = 0xEF53;
+    else if (strcmp(statfsArgs.f_basetype, "ext3") == 0) result = 0xEF53;
+    else if (strcmp(statfsArgs.f_basetype, "ext4") == 0) result = 0xEF53;
+    else if (strcmp(statfsArgs.f_basetype, "fat") == 0) result = 0x4006;
+    else if (strcmp(statfsArgs.f_basetype, "fd") == 0) result = 0xF00D1E;
+    else if (strcmp(statfsArgs.f_basetype, "fhgfs") == 0) result = 0x19830326;
+    else if (strcmp(statfsArgs.f_basetype, "fuse") == 0) result = 0x65735546;
+    else if (strcmp(statfsArgs.f_basetype, "fuseblk") == 0) result = 0x65735546;
+    else if (strcmp(statfsArgs.f_basetype, "fusectl") == 0) result = 0x65735543;
+    else if (strcmp(statfsArgs.f_basetype, "futexfs") == 0) result = 0x0BAD1DEA;
+    else if (strcmp(statfsArgs.f_basetype, "gfsgfs2") == 0) result = 0x1161970;
+    else if (strcmp(statfsArgs.f_basetype, "gfs2") == 0) result = 0x01161970;
+    else if (strcmp(statfsArgs.f_basetype, "gpfs") == 0) result = 0x47504653;
+    else if (strcmp(statfsArgs.f_basetype, "hfs") == 0) result = 0x4244;
+    else if (strcmp(statfsArgs.f_basetype, "hfsplus") == 0) result = 0x482B;
+    else if (strcmp(statfsArgs.f_basetype, "hpfs") == 0) result = 0xF995E849;
+    else if (strcmp(statfsArgs.f_basetype, "hugetlbfs") == 0) result = 0x958458F6;
+    else if (strcmp(statfsArgs.f_basetype, "inodefs") == 0) result = 0x11307854;
+    else if (strcmp(statfsArgs.f_basetype, "inotifyfs") == 0) result = 0x2BAD1DEA;
+    else if (strcmp(statfsArgs.f_basetype, "isofs") == 0) result = 0x9660;
+    else if (strcmp(statfsArgs.f_basetype, "jffs") == 0) result = 0x07C0;
+    else if (strcmp(statfsArgs.f_basetype, "jffs2") == 0) result = 0x72B6;
+    else if (strcmp(statfsArgs.f_basetype, "jfs") == 0) result = 0x3153464A;
+    else if (strcmp(statfsArgs.f_basetype, "kafs") == 0) result = 0x6B414653;
+    else if (strcmp(statfsArgs.f_basetype, "lofs") == 0) result = 0xEF53;
+    else if (strcmp(statfsArgs.f_basetype, "logfs") == 0) result = 0xC97E8168;
+    else if (strcmp(statfsArgs.f_basetype, "lustre") == 0) result = 0x0BD00BD0;
+    else if (strcmp(statfsArgs.f_basetype, "minix_old") == 0) result = 0x137F;
+    else if (strcmp(statfsArgs.f_basetype, "minix") == 0) result = 0x138F;
+    else if (strcmp(statfsArgs.f_basetype, "minix2") == 0) result = 0x2468;
+    else if (strcmp(statfsArgs.f_basetype, "minix2v2") == 0) result = 0x2478;
+    else if (strcmp(statfsArgs.f_basetype, "minix3") == 0) result = 0x4D5A;
+    else if (strcmp(statfsArgs.f_basetype, "mntfs") == 0) result = 0x01021994;
+    else if (strcmp(statfsArgs.f_basetype, "mqueue") == 0) result = 0x19800202;
+    else if (strcmp(statfsArgs.f_basetype, "msdos") == 0) result = 0x4D44;
+    else if (strcmp(statfsArgs.f_basetype, "nfs") == 0) result = 0x6969;
+    else if (strcmp(statfsArgs.f_basetype, "nfsd") == 0) result = 0x6E667364;
+    else if (strcmp(statfsArgs.f_basetype, "nilfs") == 0) result = 0x3434;
+    else if (strcmp(statfsArgs.f_basetype, "novell") == 0) result = 0x564C;
+    else if (strcmp(statfsArgs.f_basetype, "ntfs") == 0) result = 0x5346544E;
+    else if (strcmp(statfsArgs.f_basetype, "objfs") == 0) result = 0x01021994;
+    else if (strcmp(statfsArgs.f_basetype, "ocfs2") == 0) result = 0x7461636F;
+    else if (strcmp(statfsArgs.f_basetype, "openprom") == 0) result = 0x9FA1;
+    else if (strcmp(statfsArgs.f_basetype, "omfs") == 0) result = 0xC2993D87;
+    else if (strcmp(statfsArgs.f_basetype, "overlay") == 0) result = 0x794C7630;
+    else if (strcmp(statfsArgs.f_basetype, "overlayfs") == 0) result = 0x794C764F;
+    else if (strcmp(statfsArgs.f_basetype, "panfs") == 0) result = 0xAAD7AAEA;
+    else if (strcmp(statfsArgs.f_basetype, "pipefs") == 0) result = 0x50495045;
+    else if (strcmp(statfsArgs.f_basetype, "proc") == 0) result = 0x9FA0;
+    else if (strcmp(statfsArgs.f_basetype, "pstorefs") == 0) result = 0x6165676C;
+    else if (strcmp(statfsArgs.f_basetype, "qnx4") == 0) result = 0x002F;
+    else if (strcmp(statfsArgs.f_basetype, "qnx6") == 0) result = 0x68191122;
+    else if (strcmp(statfsArgs.f_basetype, "ramfs") == 0) result = 0x858458F6;
+    else if (strcmp(statfsArgs.f_basetype, "reiserfs") == 0) result = 0x52654973;
+    else if (strcmp(statfsArgs.f_basetype, "romfs") == 0) result = 0x7275;
+    else if (strcmp(statfsArgs.f_basetype, "rootfs") == 0) result = 0x53464846;
+    else if (strcmp(statfsArgs.f_basetype, "rpc_pipefs") == 0) result = 0x67596969;
+    else if (strcmp(statfsArgs.f_basetype, "samba") == 0) result = 0x517B;
+    else if (strcmp(statfsArgs.f_basetype, "securityfs") == 0) result = 0x73636673;
+    else if (strcmp(statfsArgs.f_basetype, "selinux") == 0) result = 0xF97CFF8C;
+    else if (strcmp(statfsArgs.f_basetype, "sffs") == 0) result = 0x786F4256;
+    else if (strcmp(statfsArgs.f_basetype, "sharefs") == 0) result = 0x01021994;
+    else if (strcmp(statfsArgs.f_basetype, "smb") == 0) result = 0x517B;
+    else if (strcmp(statfsArgs.f_basetype, "smb2") == 0) result = 0xFE534D42;
+    else if (strcmp(statfsArgs.f_basetype, "sockfs") == 0) result = 0x534F434B;
+    else if (strcmp(statfsArgs.f_basetype, "squashfs") == 0) result = 0x73717368;
+    else if (strcmp(statfsArgs.f_basetype, "sysfs") == 0) result = 0x62656572;
+    else if (strcmp(statfsArgs.f_basetype, "sysv2") == 0) result = 0x012FF7B6;
+    else if (strcmp(statfsArgs.f_basetype, "sysv4") == 0) result = 0x012FF7B5;
+    else if (strcmp(statfsArgs.f_basetype, "tmpfs") == 0) result = 0x01021994;
+    else if (strcmp(statfsArgs.f_basetype, "ubifs") == 0) result = 0x24051905;
+    else if (strcmp(statfsArgs.f_basetype, "udf") == 0) result = 0x15013346;
+    else if (strcmp(statfsArgs.f_basetype, "ufs") == 0) result = 0x00011954;
+    else if (strcmp(statfsArgs.f_basetype, "ufscigam") == 0) result = 0x54190100;
+    else if (strcmp(statfsArgs.f_basetype, "ufs2") == 0) result = 0x19540119;
+    else if (strcmp(statfsArgs.f_basetype, "usbdevice") == 0) result = 0x9FA2;
+    else if (strcmp(statfsArgs.f_basetype, "v9fs") == 0) result = 0x01021997;
+    else if (strcmp(statfsArgs.f_basetype, "vagrant") == 0) result = 0x786F4256;
+    else if (strcmp(statfsArgs.f_basetype, "vboxfs") == 0) result = 0x786F4256;
+    else if (strcmp(statfsArgs.f_basetype, "vmhgfs") == 0) result = 0xBACBACBC;
+    else if (strcmp(statfsArgs.f_basetype, "vxfs") == 0) result = 0xA501FCF5;
+    else if (strcmp(statfsArgs.f_basetype, "vzfs") == 0) result = 0x565A4653;
+    else if (strcmp(statfsArgs.f_basetype, "xenfs") == 0) result = 0xABBA1974;
+    else if (strcmp(statfsArgs.f_basetype, "xenix") == 0) result = 0x012FF7B4;
+    else if (strcmp(statfsArgs.f_basetype, "xfs") == 0) result = 0x58465342;
+    else if (strcmp(statfsArgs.f_basetype, "xia") == 0) result = 0x012FD16D;
+    else if (strcmp(statfsArgs.f_basetype, "udev") == 0) result = 0x01021994;
+    else if (strcmp(statfsArgs.f_basetype, "zfs") == 0) result = 0x2FC12FC1;
+
+    assert(result != -1);
+    return result;
 #else
-    #error "Platform doesn't support fstatfs"
+    #error "Platform doesn't support fstatfs or fstatvfs"
 #endif
 }
 
diff --git a/src/libraries/Native/Unix/System.Native/pal_memory.c b/src/libraries/Native/Unix/System.Native/pal_memory.c
index fd6a34de2c39a..eb76650f47b43 100644
--- a/src/libraries/Native/Unix/System.Native/pal_memory.c
+++ b/src/libraries/Native/Unix/System.Native/pal_memory.c
@@ -10,10 +10,15 @@
 
 #if HAVE_MALLOC_SIZE
     #include <malloc/malloc.h>
+    #define MALLOC_SIZE(s) malloc_size(s)
 #elif HAVE_MALLOC_USABLE_SIZE
     #include <malloc.h>
+    #define MALLOC_SIZE(s) malloc_usable_size(s)
 #elif HAVE_MALLOC_USABLE_SIZE_NP
     #include <malloc_np.h>
+    #define MALLOC_SIZE(s) malloc_usable_size(s)
+#elif defined(TARGET_SUNOS)
+    #define MALLOC_SIZE(s) (*((size_t*)(s)-1))
 #else
     #error "Platform doesn't support malloc_usable_size or malloc_size"
 #endif
@@ -67,13 +72,7 @@ void SystemNative_Free(void* ptr)
 
 uintptr_t SystemNative_GetUsableSize(void* ptr)
 {
-#if HAVE_MALLOC_SIZE
-    return malloc_size(ptr);
-#elif HAVE_MALLOC_USABLE_SIZE || HAVE_MALLOC_USABLE_SIZE_NP
-    return malloc_usable_size(ptr);
-#else
-    #error "Platform doesn't support malloc_usable_size or malloc_size"
-#endif
+    return MALLOC_SIZE(ptr);
 }
 
 void* SystemNative_Malloc(uintptr_t size)
diff --git a/src/native/corehost/bundle/extractor.cpp b/src/native/corehost/bundle/extractor.cpp
index 4e6f439083448..60c2d5389c2f6 100644
--- a/src/native/corehost/bundle/extractor.cpp
+++ b/src/native/corehost/bundle/extractor.cpp
@@ -7,6 +7,10 @@
 #include "pal.h"
 #include "utils.h"
 
+#ifdef __sun
+#include <alloca.h>
+#endif
+
 #if defined(NATIVE_LIBS_EMBEDDED)
 extern "C"
 {