On Wed, Dec 22, 2021 at 12:35 AM <guoren@xxxxxxxxxx> wrote: > > From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> > > Currently, most 64-bit architectures (x86, parisc, powerpc, arm64, > s390, mips, sparc) have supported COMPAT mode. But they all have > history issues and can't use standard linux unistd.h. RISC-V would > be first standard __SYSCALL_COMPAT user of include/uapi/asm-generic > /unistd.h. > > The patchset are based on v5.16-rc6, you can compare rv64-compat32 > v.s. rv32-whole in qemu with following step: > > - Prepare rv32 rootfs & fw_jump.bin by buildroot.org > $ git clone git://git.busybox.net/buildroot > $ cd buildroot > $ make qemu_riscv32_virt_defconfig O=qemu_riscv32_virt_defconfig > $ make -C qemu_riscv32_virt_defconfig > $ make qemu_riscv64_virt_defconfig O=qemu_riscv64_virt_defconfig > $ make -C qemu_riscv64_virt_defconfig > (Got fw_jump.bin & rootfs.ext2 in qemu_riscvXX_virt_defconfig/images) > > - Prepare Linux rv32 & rv64 Image > $ git clone git@xxxxxxxxxx:c-sky/csky-linux.git -b riscv_compat_v1 linux > $ cd linux > $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ rv32_defconfig > $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ Image > $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ defconfig You need menuconfig to enable CONFIG_COMPAT, here. I forgot add CONFIG_COMPAT in defconfig or make CONFIG_COMPAT with def_bool. > $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ Image > > - Prepare Qemu: (made by LIU Zhiwei <zhiwei_liu@xxxxxxxxx>) > $ git clone https://github.com/romanheros/qemu.git -b riscv-upstream-uxl-v5 > $ cd qemu > $ ./configure --target-list="riscv64-softmmu riscv32-softmmu" > $ make > > - Run rv64 with rv32 rootfs in compat mode: > $ ./build/qemu-system-riscv64 -cpu rv64,x-h=true -M virt -m 64m -nographic -bios qemu_riscv64_virt_defconfig/images/fw_jump.bin -kernel build-rv64/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0 > > QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8) > OpenSBI v0.9 > [ 0.000000] Linux version 5.16.0-rc6-00013-g60f122c486d0 (guoren@guoren-Z87-HD3) (riscv64-unknown-linux-gnu-gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.37) #62 SMP Tue Dec 21 22:54:05 CST 2021 > [ 0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000 > [ 0.000000] Machine model: riscv-virtio,qemu > [ 0.000000] earlycon: sbi0 at I/O port 0x0 (options '') > [ 0.000000] printk: bootconsole [sbi0] enabled > [ 0.000000] efi: UEFI not found. > [ 0.000000] Zone ranges: > [ 0.000000] DMA32 [mem 0x0000000080200000-0x0000000083ffffff] > [ 0.000000] Normal empty > [ 0.000000] Movable zone start for each node > [ 0.000000] Early memory node ranges > [ 0.000000] node 0: [mem 0x0000000080200000-0x0000000083ffffff] > [ 0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x0000000083ffffff] > [ 0.000000] SBI specification v0.2 detected > [ 0.000000] SBI implementation ID=0x1 Version=0x9 > [ 0.000000] SBI TIME extension detected > [ 0.000000] SBI IPI extension detected > [ 0.000000] SBI RFENCE extension detected > [ 0.000000] SBI v0.2 HSM extension detected > [ 0.000000] riscv: compat: 32bit U-mode applications support > [ 0.000000] riscv: ISA extensions acdfhimsu > [ 0.000000] riscv: ELF capabilities acdfim > [ 0.000000] percpu: Embedded 17 pages/cpu s30696 r8192 d30744 u69632 > [ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 15655 > [ 0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi > [ 0.000000] Dentry cache hash table entries: 8192 (order: 4, 65536 bytes, linear) > [ 0.000000] Inode-cache hash table entries: 4096 (order: 3, 32768 bytes, linear) > [ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off > [ 0.000000] Virtual kernel memory layout: > [ 0.000000] fixmap : 0xffffffcefee00000 - 0xffffffceff000000 (2048 kB) > [ 0.000000] pci io : 0xffffffceff000000 - 0xffffffcf00000000 ( 16 MB) > [ 0.000000] vmemmap : 0xffffffcf00000000 - 0xffffffcfffffffff (4095 MB) > [ 0.000000] vmalloc : 0xffffffd000000000 - 0xffffffdfffffffff (65535 MB) > [ 0.000000] lowmem : 0xffffffe000000000 - 0xffffffe003e00000 ( 62 MB) > [ 0.000000] kernel : 0xffffffff80000000 - 0xffffffffffffffff (2047 MB) > [ 0.000000] Memory: 43952K/63488K available (6180K kernel code, 4873K rwdata, 2048K rodata, 2146K init, 297K bss, 19536K reserved, 0K cma-reserved) > [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1 > [ 0.000000] rcu: Hierarchical RCU implementation. > [ 0.000000] rcu: RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1. > [ 0.000000] rcu: RCU debug extended QS entry/exit. > [ 0.000000] Tracing variant of Tasks RCU enabled. > [ 0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies. > [ 0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1 > [ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0 > [ 0.000000] riscv-intc: 64 local interrupts mapped > [ 0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts. > ... > Welcome to Buildroot > buildroot login: root > # cat /proc/cpuinfo > processor : 0 > hart : 0 > isa : rv64imafdcsuh > mmu : sv48 > > # file /bin/busybox > /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped > # cat /proc/meminfo > MemTotal: 46096 kB > MemFree: 30116 kB > MemAvailable: 32824 kB > Buffers: 664 kB > Cached: 3900 kB > SwapCached: 0 kB > Active: 3164 kB > Inactive: 1920 kB > Active(anon): 40 kB > Inactive(anon): 524 kB > Active(file): 3124 kB > Inactive(file): 1396 kB > Unevictable: 0 kB > Mlocked: 0 kB > SwapTotal: 0 kB > SwapFree: 0 kB > Dirty: 8 kB > Writeback: 0 kB > AnonPages: 556 kB > Mapped: 2084 kB > Shmem: 44 kB > KReclaimable: 964 kB > Slab: 5760 kB > SReclaimable: 964 kB > SUnreclaim: 4796 kB > KernelStack: 624 kB > PageTables: 132 kB > NFS_Unstable: 0 kB > Bounce: 0 kB > WritebackTmp: 0 kB > CommitLimit: 23048 kB > Committed_AS: 2088 kB > VmallocTotal: 67108863 kB > VmallocUsed: 636 kB > VmallocChunk: 0 kB > Percpu: 80 kB > # > > - Run rv32 with rv32 rootfs: > $ ./build/qemu-system-riscv32 -cpu rv32,x-h=true -M virt -m 64m -nographic -bios qemu_riscv32_virt_defconfig/images/fw_jump.bin -kernel build-rv32/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0 > > QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8) > OpenSBI v0.9 > [ 0.000000] Linux version 5.16.0-rc6-00013-g60f122c486d0 (guoren@guoren-Z87-HD3) (riscv32-buildroot-linux-gnu-gcc.br_real (Buildroot 2021.11-201-g7600ca7960-dirty) 10.3.0, GNU ld (GNU Binutils) 2.36.1) #4 SMP Tue Dec 21 22:54:43 CST 2021 > [ 0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80400000 > [ 0.000000] Machine model: riscv-virtio,qemu > [ 0.000000] earlycon: sbi0 at I/O port 0x0 (options '') > [ 0.000000] printk: bootconsole [sbi0] enabled > [ 0.000000] efi: UEFI not found. > [ 0.000000] Zone ranges: > [ 0.000000] Normal [mem 0x0000000080400000-0x0000000083ffffff] > [ 0.000000] Movable zone start for each node > [ 0.000000] Early memory node ranges > [ 0.000000] node 0: [mem 0x0000000080400000-0x0000000083ffffff] > [ 0.000000] Initmem setup node 0 [mem 0x0000000080400000-0x0000000083ffffff] > [ 0.000000] SBI specification v0.2 detected > [ 0.000000] SBI implementation ID=0x1 Version=0x9 > [ 0.000000] SBI TIME extension detected > [ 0.000000] SBI IPI extension detected > [ 0.000000] SBI RFENCE extension detected > [ 0.000000] SBI v0.2 HSM extension detected > [ 0.000000] riscv: ISA extensions acdfhimsu > [ 0.000000] riscv: ELF capabilities acdfim > [ 0.000000] percpu: Embedded 12 pages/cpu s16600 r8192 d24360 u49152 > [ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 15240 > [ 0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi > [ 0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes, linear) > [ 0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes, linear) > [ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off > [ 0.000000] Virtual kernel memory layout: > [ 0.000000] fixmap : 0x9dc00000 - 0x9e000000 (4096 kB) > [ 0.000000] pci io : 0x9e000000 - 0x9f000000 ( 16 MB) > [ 0.000000] vmemmap : 0x9f000000 - 0x9fffffff ( 15 MB) > [ 0.000000] vmalloc : 0xa0000000 - 0xbfffffff ( 511 MB) > [ 0.000000] lowmem : 0xc0000000 - 0xc3c00000 ( 60 MB) > [ 0.000000] Memory: 35332K/61440K available (6073K kernel code, 8814K rwdata, 4096K rodata, 4160K init, 241K bss, 26108K reserved, 0K cma-reserved) > [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1 > [ 0.000000] rcu: Hierarchical RCU implementation. > [ 0.000000] rcu: RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1. > [ 0.000000] rcu: RCU debug extended QS entry/exit. > [ 0.000000] Tracing variant of Tasks RCU enabled. > [ 0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies. > [ 0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1 > [ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0 > [ 0.000000] riscv-intc: 32 local interrupts mapped > [ 0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts. > ... > Welcome to Buildroot > buildroot login: root > # cat /proc/cpuinfo > processor : 0 > hart : 0 > isa : rv32imafdcsuh > mmu : sv32 > > # file /bin/busybox > /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped > # cat /proc/meminfo > MemTotal: 39492 kB > MemFree: 26756 kB > MemAvailable: 29552 kB > Buffers: 668 kB > Cached: 3908 kB > SwapCached: 0 kB > Active: 3156 kB > Inactive: 1936 kB > Active(anon): 40 kB > Inactive(anon): 520 kB > Active(file): 3116 kB > Inactive(file): 1416 kB > Unevictable: 0 kB > Mlocked: 0 kB > SwapTotal: 0 kB > SwapFree: 0 kB > Dirty: 0 kB > Writeback: 0 kB > AnonPages: 552 kB > Mapped: 2144 kB > Shmem: 44 kB > KReclaimable: 624 kB > Slab: 3660 kB > SReclaimable: 624 kB > SUnreclaim: 3036 kB > KernelStack: 312 kB > PageTables: 92 kB > NFS_Unstable: 0 kB > Bounce: 0 kB > WritebackTmp: 0 kB > CommitLimit: 19744 kB > Committed_AS: 2088 kB > VmallocTotal: 524287 kB > VmallocUsed: 12 kB > VmallocChunk: 0 kB > Percpu: 60 kB > # > > Some conclusions: > - rv32 linux kernel code, data sizes are larger than rv64. > (complier's issue?) > - rv32 kernel runtime KernelStack, Slab... are smaller, > but not so much for memory footprint saving. > - Totally rv64 kernel is much better than rv32. > - Qemu, kernel, rv32 = rv64 defconfig, rootfs, opensbi > are the same in this comparison. > > Guo Ren (13): > syscalls: compat: Fix the missing part for __SYSCALL_COMPAT > riscv: Fixup difference with defconfig > riscv: compat: Add basic compat date type implementation > riscv: compat: Re-implement TASK_SIZE for COMPAT_32BIT > riscv: compat: syscall: Add compat_sys_call_table implementation > riscv: compat: syscall: Add entry.S implementation > riscv: compat: Add elf.h implementation > riscv: compat: Add COMPAT Kbuild skeletal support > riscv: compat: init: Add hw-cap detect in setup_arch > riscv: compat: vdso: Add rv32 VDSO base code implementation > riscv: compat: vdso: Add setup additional pages implementation > riscv: compat: signal: Add rt_frame implementation > riscv: compat: ptrace: Add compat_arch_ptrace implement > > arch/riscv/Kconfig | 22 ++ > arch/riscv/Makefile | 5 + > arch/riscv/configs/rv32_defconfig | 20 +- > arch/riscv/include/asm/compat.h | 259 ++++++++++++++++++ > arch/riscv/include/asm/csr.h | 7 + > arch/riscv/include/asm/elf.h | 53 +++- > arch/riscv/include/asm/mmu.h | 1 + > arch/riscv/include/asm/pgtable.h | 11 +- > arch/riscv/include/asm/processor.h | 10 + > arch/riscv/include/asm/syscall.h | 3 + > arch/riscv/include/asm/thread_info.h | 1 + > arch/riscv/include/asm/vdso.h | 9 + > arch/riscv/kernel/Makefile | 3 + > arch/riscv/kernel/compat_signal.c | 243 ++++++++++++++++ > arch/riscv/kernel/compat_syscall_table.c | 84 ++++++ > arch/riscv/kernel/compat_vdso/.gitignore | 2 + > arch/riscv/kernel/compat_vdso/Makefile | 68 +++++ > arch/riscv/kernel/compat_vdso/compat_vdso.S | 8 + > .../kernel/compat_vdso/compat_vdso.lds.S | 3 + > arch/riscv/kernel/compat_vdso/flush_icache.S | 3 + > .../compat_vdso/gen_compat_vdso_offsets.sh | 5 + > arch/riscv/kernel/compat_vdso/getcpu.S | 3 + > arch/riscv/kernel/compat_vdso/note.S | 3 + > arch/riscv/kernel/compat_vdso/rt_sigreturn.S | 3 + > arch/riscv/kernel/entry.S | 18 +- > arch/riscv/kernel/process.c | 32 +++ > arch/riscv/kernel/ptrace.c | 87 +++++- > arch/riscv/kernel/setup.c | 5 + > arch/riscv/kernel/signal.c | 13 +- > arch/riscv/kernel/vdso.c | 104 +++++-- > arch/riscv/kernel/vdso/vdso.S | 6 +- > drivers/firmware/efi/libstub/efi-stub.c | 2 +- > include/uapi/asm-generic/unistd.h | 4 +- > tools/include/uapi/asm-generic/unistd.h | 4 +- > 34 files changed, 1055 insertions(+), 49 deletions(-) > create mode 100644 arch/riscv/include/asm/compat.h > create mode 100644 arch/riscv/kernel/compat_signal.c > create mode 100644 arch/riscv/kernel/compat_syscall_table.c > create mode 100644 arch/riscv/kernel/compat_vdso/.gitignore > create mode 100644 arch/riscv/kernel/compat_vdso/Makefile > create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.S > create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.lds.S > create mode 100644 arch/riscv/kernel/compat_vdso/flush_icache.S > create mode 100755 arch/riscv/kernel/compat_vdso/gen_compat_vdso_offsets.sh > create mode 100644 arch/riscv/kernel/compat_vdso/getcpu.S > create mode 100644 arch/riscv/kernel/compat_vdso/note.S > create mode 100644 arch/riscv/kernel/compat_vdso/rt_sigreturn.S > > -- > 2.25.1 > -- Best Regards Guo Ren ML: https://lore.kernel.org/linux-csky/
