[PATCH v2] MIPS: remove support for trap and emulate KVM

From: Paolo Bonzini <pbonzini(a)redhat.com&gt; This support was limited to the Malta board, drop it. I do not have a machine that can run VZ KVM, so I am assuming that it works for -M malta as well. Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com&gt; Signed-off-by: Philippe Mathieu-Daudé <philmd(a)linaro.org&gt; --- Since Paolo's v1: - Remove cpu_mips_kvm_um_phys_to_kseg0() declaration in "cpu.h" - Remove unused KVM_KSEG0_BASE/KVM_KSEG2_BASE definitions - Use USEG_LIMIT/KSEG0_BASE instead of magic values /* Check where the kernel has been linked */ - if (!(kernel_entry & 0x80000000ll)) { - error_report("CONFIG_KVM_GUEST kernels are not supported"); + if (kernel_entry <= USEG_LIMIT) { + error_report("Trap-and-Emul kernels (Linux CONFIG_KVM_GUEST)" + " are not supported"); - env->CP0_EBase = (cs->cpu_index & 0x3FF) | (int32_t)0x80000000; + env->CP0_EBase = KSEG0_BASE | (cs->cpu_index & 0x3FF); --- docs/about/deprecated.rst | 9 ------- docs/about/removed-features.rst | 9 +++++++ hw/mips/malta.c | 46 +++++---------------------------- target/mips/cpu.c | 7 +---- target/mips/cpu.h | 3 --- target/mips/internal.h | 3 --- target/mips/kvm.c | 11 +------- target/mips/sysemu/addr.c | 17 ------------ target/mips/sysemu/physaddr.c | 13 ---------- 9 files changed, 18 insertions(+), 100 deletions(-) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 93affe3669..b28f50b22f 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -199,15 +199,6 @@ deprecated. Use ``sections`` instead. Member ``section-size`` in return value elements with meta-type ``uint64`` is deprecated. Use ``sections`` instead. -System accelerators -------------------- - -MIPS ``Trap-and-Emul`` KVM support (since 6.0) -'''''''''''''''''''''''''''''''''''''''''''''' - -The MIPS ``Trap-and-Emul`` KVM host and guest support has been removed -from Linux upstream kernel, declare it deprecated. - Host Architectures ------------------ diff --git a/docs/about/removed-features.rst b/docs/about/removed-features.rst index 63df9848fd..22b4b5d128 100644 --- a/docs/about/removed-features.rst +++ b/docs/about/removed-features.rst @@ -617,6 +617,15 @@ x86 ``Icelake-Client`` CPU (removed in 7.1) There isn't ever Icelake Client CPU, it is some wrong and imaginary one. Use ``Icelake-Server`` instead. +System accelerators +------------------- + +MIPS "Trap-and-Emulate" KVM support (removed in 8.0) +'''''''''''''''''''''''''''''''''''''''''''''''''''' + +The MIPS "Trap-and-Emulate" KVM host and guest support was removed +from Linux in 2021, and is not supported anymore by QEMU either. + System emulator machines ------------------------ diff --git a/hw/mips/malta.c b/hw/mips/malta.c index e5050ecd3c..fed8b65f1e 100644 --- a/hw/mips/malta.c +++ b/hw/mips/malta.c @@ -58,6 +58,7 @@ #include "semihosting/semihost.h" #include "hw/mips/cps.h" #include "hw/qdev-clock.h" +#include "target/mips/internal.h" #define ENVP_PADDR 0x2000 #define ENVP_VADDR cpu_mips_phys_to_kseg0(NULL, ENVP_PADDR) @@ -870,7 +871,6 @@ static uint64_t load_kernel(void) uint32_t *prom_buf; long prom_size; int prom_index = 0; - uint64_t (*xlate_to_kseg0) (void *opaque, uint64_t addr); uint8_t rng_seed[32]; char rng_seed_hex[sizeof(rng_seed) * 2 + 1]; size_t rng_seed_prom_offset; @@ -894,19 +894,10 @@ static uint64_t load_kernel(void) } /* Check where the kernel has been linked */ - if (kernel_entry & 0x80000000ll) { - if (kvm_enabled()) { - error_report("KVM guest kernels must be linked in useg. " - "Did you forget to enable CONFIG_KVM_GUEST?"); - exit(1); - } - - xlate_to_kseg0 = cpu_mips_phys_to_kseg0; - } else { - /* if kernel entry is in useg it is probably a KVM T&E kernel */ - mips_um_ksegs_enable(); - - xlate_to_kseg0 = cpu_mips_kvm_um_phys_to_kseg0; + if (kernel_entry <= USEG_LIMIT) { + error_report("Trap-and-Emul kernels (Linux CONFIG_KVM_GUEST)" + " are not supported"); + exit(1); } /* load initrd */ @@ -947,7 +938,7 @@ static uint64_t load_kernel(void) if (initrd_size > 0) { prom_set(prom_buf, prom_index++, "rd_start=0x%" PRIx64 " rd_size=%" PRId64 " %s", - xlate_to_kseg0(NULL, initrd_offset), + cpu_mips_phys_to_kseg0(NULL, initrd_offset), initrd_size, loaderparams.kernel_cmdline); } else { prom_set(prom_buf, prom_index++, "%s", loaderparams.kernel_cmdline); @@ -1039,11 +1030,6 @@ static void main_cpu_reset(void *opaque) } malta_mips_config(cpu); - - if (kvm_enabled()) { - /* Start running from the bootloader we wrote to end of RAM */ - env->active_tc.PC = 0x40000000 + loaderparams.ram_low_size; - } } static void create_cpu_without_cps(MachineState *ms, MaltaState *s, @@ -1177,13 +1163,7 @@ void mips_malta_init(MachineState *machine) fl_idx++; if (kernel_filename) { ram_low_size = MIN(ram_size, 256 * MiB); - /* For KVM we reserve 1MB of RAM for running bootloader */ - if (kvm_enabled()) { - ram_low_size -= 0x100000; - bootloader_run_addr = cpu_mips_kvm_um_phys_to_kseg0(NULL, ram_low_size); - } else { - bootloader_run_addr = cpu_mips_phys_to_kseg0(NULL, RESET_ADDRESS); - } + bootloader_run_addr = cpu_mips_phys_to_kseg0(NULL, RESET_ADDRESS); /* Write a small bootloader to the flash location. */ loaderparams.ram_size = ram_size; @@ -1200,20 +1180,8 @@ void mips_malta_init(MachineState *machine) write_bootloader_nanomips(memory_region_get_ram_ptr(bios), bootloader_run_addr, kernel_entry); } - if (kvm_enabled()) { - /* Write the bootloader code @ the end of RAM, 1MB reserved */ - write_bootloader(memory_region_get_ram_ptr(ram_low_preio) + - ram_low_size, - bootloader_run_addr, kernel_entry); - } } else { target_long bios_size = FLASH_SIZE; - /* The flash region isn't executable from a KVM guest */ - if (kvm_enabled()) { - error_report("KVM enabled but no -kernel argument was specified. " - "Booting from flash is not supported with KVM."); - exit(1); - } /* Load firmware from flash. */ if (!dinfo) { /* Load a BIOS image. */ diff --git a/target/mips/cpu.c b/target/mips/cpu.c index 17bbcbf5ff..f8c8e0ba39 100644 --- a/target/mips/cpu.c +++ b/target/mips/cpu.c @@ -291,12 +291,7 @@ static void mips_cpu_reset_hold(Object *obj) env->tlb->tlb_in_use = env->tlb->nb_tlb; env->CP0_Wired = 0; env->CP0_GlobalNumber = (cs->cpu_index & 0xFF) << CP0GN_VPId; - env->CP0_EBase = (cs->cpu_index & 0x3FF); - if (mips_um_ksegs_enabled()) { - env->CP0_EBase |= 0x40000000; - } else { - env->CP0_EBase |= (int32_t)0x80000000; - } + env->CP0_EBase = KSEG0_BASE | (cs->cpu_index & 0x3FF); if (env->CP0_Config3 & (1 << CP0C3_CMGCR)) { env->CP0_CMGCRBase = 0x1fbf8000 >> 4; } diff --git a/target/mips/cpu.h b/target/mips/cpu.h index 0a085643a3..caf2b06911 100644 --- a/target/mips/cpu.h +++ b/target/mips/cpu.h @@ -1296,11 +1296,8 @@ void cpu_set_exception_base(int vp_index, target_ulong address); uint64_t cpu_mips_kseg0_to_phys(void *opaque, uint64_t addr); uint64_t cpu_mips_phys_to_kseg0(void *opaque, uint64_t addr); -uint64_t cpu_mips_kvm_um_phys_to_kseg0(void *opaque, uint64_t addr); uint64_t cpu_mips_kseg1_to_phys(void *opaque, uint64_t addr); uint64_t cpu_mips_phys_to_kseg1(void *opaque, uint64_t addr); -bool mips_um_ksegs_enabled(void); -void mips_um_ksegs_enable(void); #if !defined(CONFIG_USER_ONLY) diff --git a/target/mips/internal.h b/target/mips/internal.h index 57b312689a..4b0031d10d 100644 --- a/target/mips/internal.h +++ b/target/mips/internal.h @@ -99,9 +99,6 @@ int mips_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg); #define KSEG2_BASE ((target_ulong)(int32_t)0xC0000000UL) #define KSEG3_BASE ((target_ulong)(int32_t)0xE0000000UL) -#define KVM_KSEG0_BASE ((target_ulong)(int32_t)0x40000000UL) -#define KVM_KSEG2_BASE ((target_ulong)(int32_t)0x60000000UL) - #if !defined(CONFIG_USER_ONLY) enum { diff --git a/target/mips/kvm.c b/target/mips/kvm.c index bcb8e06b2c..c14e8f550f 100644 --- a/target/mips/kvm.c +++ b/target/mips/kvm.c @@ -1268,25 +1268,16 @@ int kvm_arch_msi_data_to_gsi(uint32_t data) int mips_kvm_type(MachineState *machine, const char *vm_type) { -#if defined(KVM_CAP_MIPS_VZ) || defined(KVM_CAP_MIPS_TE) +#if defined(KVM_CAP_MIPS_VZ) int r; KVMState *s = KVM_STATE(machine->accelerator); -#endif -#if defined(KVM_CAP_MIPS_VZ) r = kvm_check_extension(s, KVM_CAP_MIPS_VZ); if (r > 0) { return KVM_VM_MIPS_VZ; } #endif -#if defined(KVM_CAP_MIPS_TE) - r = kvm_check_extension(s, KVM_CAP_MIPS_TE); - if (r > 0) { - return KVM_VM_MIPS_TE; - } -#endif - return -1; } diff --git a/target/mips/sysemu/addr.c b/target/mips/sysemu/addr.c index 86f1c129c9..4f025be44a 100644 --- a/target/mips/sysemu/addr.c +++ b/target/mips/sysemu/addr.c @@ -23,8 +23,6 @@ #include "qemu/osdep.h" #include "cpu.h" -static int mips_um_ksegs; - uint64_t cpu_mips_kseg0_to_phys(void *opaque, uint64_t addr) { return addr & 0x1fffffffll; @@ -35,11 +33,6 @@ uint64_t cpu_mips_phys_to_kseg0(void *opaque, uint64_t addr) return addr | ~0x7fffffffll; } -uint64_t cpu_mips_kvm_um_phys_to_kseg0(void *opaque, uint64_t addr) -{ - return addr | 0x40000000ll; -} - uint64_t cpu_mips_kseg1_to_phys(void *opaque, uint64_t addr) { return addr & 0x1fffffffll; @@ -49,13 +42,3 @@ uint64_t cpu_mips_phys_to_kseg1(void *opaque, uint64_t addr) { return (addr & 0x1fffffffll) | 0xffffffffa0000000ll; } - -bool mips_um_ksegs_enabled(void) -{ - return mips_um_ksegs; -} - -void mips_um_ksegs_enable(void) -{ - mips_um_ksegs = 1; -} diff --git a/target/mips/sysemu/physaddr.c b/target/mips/sysemu/physaddr.c index 1918633aa1..2970df8a09 100644 --- a/target/mips/sysemu/physaddr.c +++ b/target/mips/sysemu/physaddr.c @@ -130,19 +130,6 @@ int get_physical_address(CPUMIPSState *env, hwaddr *physical, /* effective address (modified for KVM T&E kernel segments) */ target_ulong address = real_address; - if (mips_um_ksegs_enabled()) { - /* KVM T&E adds guest kernel segments in useg */ - if (real_address >= KVM_KSEG0_BASE) { - if (real_address < KVM_KSEG2_BASE) { - /* kseg0 */ - address += KSEG0_BASE - KVM_KSEG0_BASE; - } else if (real_address <= USEG_LIMIT) { - /* kseg2/3 */ - address += KSEG2_BASE - KVM_KSEG2_BASE; - } - } - } - if (address <= USEG_LIMIT) { /* useg */ uint16_t segctl; -- 2.38.1