From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- arch/mips/math-emu/me-debugfs.c | 353 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 353 insertions(+) create mode 100644 arch/mips/math-emu/me-debugfs.c (limited to 'arch/mips/math-emu/me-debugfs.c') diff --git a/arch/mips/math-emu/me-debugfs.c b/arch/mips/math-emu/me-debugfs.c new file mode 100644 index 000000000..aeddf7aec --- /dev/null +++ b/arch/mips/math-emu/me-debugfs.c @@ -0,0 +1,353 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +DEFINE_PER_CPU(struct mips_fpu_emulator_stats, fpuemustats); + +static int fpuemu_stat_get(void *data, u64 *val) +{ + int cpu; + unsigned long sum = 0; + + for_each_online_cpu(cpu) { + struct mips_fpu_emulator_stats *ps; + local_t *pv; + + ps = &per_cpu(fpuemustats, cpu); + pv = (void *)ps + (unsigned long)data; + sum += local_read(pv); + } + *val = sum; + return 0; +} +DEFINE_SIMPLE_ATTRIBUTE(fops_fpuemu_stat, fpuemu_stat_get, NULL, "%llu\n"); + +/* + * Used to obtain names for a debugfs instruction counter, given field name + * in fpuemustats structure. For example, for input "cmp_sueq_d", the output + * would be "cmp.sueq.d". This is needed since dots are not allowed to be + * used in structure field names, and are, on the other hand, desired to be + * used in debugfs item names to be clearly associated to corresponding + * MIPS FPU instructions. + */ +static void adjust_instruction_counter_name(char *out_name, char *in_name, size_t len) +{ + int i = 0; + + strscpy(out_name, in_name, len); + while (in_name[i] != '\0') { + if (out_name[i] == '_') + out_name[i] = '.'; + i++; + } +} + +static int fpuemustats_clear_show(struct seq_file *s, void *unused) +{ + __this_cpu_write((fpuemustats).emulated, 0); + __this_cpu_write((fpuemustats).loads, 0); + __this_cpu_write((fpuemustats).stores, 0); + __this_cpu_write((fpuemustats).branches, 0); + __this_cpu_write((fpuemustats).cp1ops, 0); + __this_cpu_write((fpuemustats).cp1xops, 0); + __this_cpu_write((fpuemustats).errors, 0); + __this_cpu_write((fpuemustats).ieee754_inexact, 0); + __this_cpu_write((fpuemustats).ieee754_underflow, 0); + __this_cpu_write((fpuemustats).ieee754_overflow, 0); + __this_cpu_write((fpuemustats).ieee754_zerodiv, 0); + __this_cpu_write((fpuemustats).ieee754_invalidop, 0); + __this_cpu_write((fpuemustats).ds_emul, 0); + + __this_cpu_write((fpuemustats).abs_s, 0); + __this_cpu_write((fpuemustats).abs_d, 0); + __this_cpu_write((fpuemustats).add_s, 0); + __this_cpu_write((fpuemustats).add_d, 0); + __this_cpu_write((fpuemustats).bc1eqz, 0); + __this_cpu_write((fpuemustats).bc1nez, 0); + __this_cpu_write((fpuemustats).ceil_w_s, 0); + __this_cpu_write((fpuemustats).ceil_w_d, 0); + __this_cpu_write((fpuemustats).ceil_l_s, 0); + __this_cpu_write((fpuemustats).ceil_l_d, 0); + __this_cpu_write((fpuemustats).class_s, 0); + __this_cpu_write((fpuemustats).class_d, 0); + __this_cpu_write((fpuemustats).cmp_af_s, 0); + __this_cpu_write((fpuemustats).cmp_af_d, 0); + __this_cpu_write((fpuemustats).cmp_eq_s, 0); + __this_cpu_write((fpuemustats).cmp_eq_d, 0); + __this_cpu_write((fpuemustats).cmp_le_s, 0); + __this_cpu_write((fpuemustats).cmp_le_d, 0); + __this_cpu_write((fpuemustats).cmp_lt_s, 0); + __this_cpu_write((fpuemustats).cmp_lt_d, 0); + __this_cpu_write((fpuemustats).cmp_ne_s, 0); + __this_cpu_write((fpuemustats).cmp_ne_d, 0); + __this_cpu_write((fpuemustats).cmp_or_s, 0); + __this_cpu_write((fpuemustats).cmp_or_d, 0); + __this_cpu_write((fpuemustats).cmp_ueq_s, 0); + __this_cpu_write((fpuemustats).cmp_ueq_d, 0); + __this_cpu_write((fpuemustats).cmp_ule_s, 0); + __this_cpu_write((fpuemustats).cmp_ule_d, 0); + __this_cpu_write((fpuemustats).cmp_ult_s, 0); + __this_cpu_write((fpuemustats).cmp_ult_d, 0); + __this_cpu_write((fpuemustats).cmp_un_s, 0); + __this_cpu_write((fpuemustats).cmp_un_d, 0); + __this_cpu_write((fpuemustats).cmp_une_s, 0); + __this_cpu_write((fpuemustats).cmp_une_d, 0); + __this_cpu_write((fpuemustats).cmp_saf_s, 0); + __this_cpu_write((fpuemustats).cmp_saf_d, 0); + __this_cpu_write((fpuemustats).cmp_seq_s, 0); + __this_cpu_write((fpuemustats).cmp_seq_d, 0); + __this_cpu_write((fpuemustats).cmp_sle_s, 0); + __this_cpu_write((fpuemustats).cmp_sle_d, 0); + __this_cpu_write((fpuemustats).cmp_slt_s, 0); + __this_cpu_write((fpuemustats).cmp_slt_d, 0); + __this_cpu_write((fpuemustats).cmp_sne_s, 0); + __this_cpu_write((fpuemustats).cmp_sne_d, 0); + __this_cpu_write((fpuemustats).cmp_sor_s, 0); + __this_cpu_write((fpuemustats).cmp_sor_d, 0); + __this_cpu_write((fpuemustats).cmp_sueq_s, 0); + __this_cpu_write((fpuemustats).cmp_sueq_d, 0); + __this_cpu_write((fpuemustats).cmp_sule_s, 0); + __this_cpu_write((fpuemustats).cmp_sule_d, 0); + __this_cpu_write((fpuemustats).cmp_sult_s, 0); + __this_cpu_write((fpuemustats).cmp_sult_d, 0); + __this_cpu_write((fpuemustats).cmp_sun_s, 0); + __this_cpu_write((fpuemustats).cmp_sun_d, 0); + __this_cpu_write((fpuemustats).cmp_sune_s, 0); + __this_cpu_write((fpuemustats).cmp_sune_d, 0); + __this_cpu_write((fpuemustats).cvt_d_l, 0); + __this_cpu_write((fpuemustats).cvt_d_s, 0); + __this_cpu_write((fpuemustats).cvt_d_w, 0); + __this_cpu_write((fpuemustats).cvt_l_s, 0); + __this_cpu_write((fpuemustats).cvt_l_d, 0); + __this_cpu_write((fpuemustats).cvt_s_d, 0); + __this_cpu_write((fpuemustats).cvt_s_l, 0); + __this_cpu_write((fpuemustats).cvt_s_w, 0); + __this_cpu_write((fpuemustats).cvt_w_s, 0); + __this_cpu_write((fpuemustats).cvt_w_d, 0); + __this_cpu_write((fpuemustats).div_s, 0); + __this_cpu_write((fpuemustats).div_d, 0); + __this_cpu_write((fpuemustats).floor_w_s, 0); + __this_cpu_write((fpuemustats).floor_w_d, 0); + __this_cpu_write((fpuemustats).floor_l_s, 0); + __this_cpu_write((fpuemustats).floor_l_d, 0); + __this_cpu_write((fpuemustats).maddf_s, 0); + __this_cpu_write((fpuemustats).maddf_d, 0); + __this_cpu_write((fpuemustats).max_s, 0); + __this_cpu_write((fpuemustats).max_d, 0); + __this_cpu_write((fpuemustats).maxa_s, 0); + __this_cpu_write((fpuemustats).maxa_d, 0); + __this_cpu_write((fpuemustats).min_s, 0); + __this_cpu_write((fpuemustats).min_d, 0); + __this_cpu_write((fpuemustats).mina_s, 0); + __this_cpu_write((fpuemustats).mina_d, 0); + __this_cpu_write((fpuemustats).mov_s, 0); + __this_cpu_write((fpuemustats).mov_d, 0); + __this_cpu_write((fpuemustats).msubf_s, 0); + __this_cpu_write((fpuemustats).msubf_d, 0); + __this_cpu_write((fpuemustats).mul_s, 0); + __this_cpu_write((fpuemustats).mul_d, 0); + __this_cpu_write((fpuemustats).neg_s, 0); + __this_cpu_write((fpuemustats).neg_d, 0); + __this_cpu_write((fpuemustats).recip_s, 0); + __this_cpu_write((fpuemustats).recip_d, 0); + __this_cpu_write((fpuemustats).rint_s, 0); + __this_cpu_write((fpuemustats).rint_d, 0); + __this_cpu_write((fpuemustats).round_w_s, 0); + __this_cpu_write((fpuemustats).round_w_d, 0); + __this_cpu_write((fpuemustats).round_l_s, 0); + __this_cpu_write((fpuemustats).round_l_d, 0); + __this_cpu_write((fpuemustats).rsqrt_s, 0); + __this_cpu_write((fpuemustats).rsqrt_d, 0); + __this_cpu_write((fpuemustats).sel_s, 0); + __this_cpu_write((fpuemustats).sel_d, 0); + __this_cpu_write((fpuemustats).seleqz_s, 0); + __this_cpu_write((fpuemustats).seleqz_d, 0); + __this_cpu_write((fpuemustats).selnez_s, 0); + __this_cpu_write((fpuemustats).selnez_d, 0); + __this_cpu_write((fpuemustats).sqrt_s, 0); + __this_cpu_write((fpuemustats).sqrt_d, 0); + __this_cpu_write((fpuemustats).sub_s, 0); + __this_cpu_write((fpuemustats).sub_d, 0); + __this_cpu_write((fpuemustats).trunc_w_s, 0); + __this_cpu_write((fpuemustats).trunc_w_d, 0); + __this_cpu_write((fpuemustats).trunc_l_s, 0); + __this_cpu_write((fpuemustats).trunc_l_d, 0); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(fpuemustats_clear); + +static int __init debugfs_fpuemu(void) +{ + struct dentry *fpuemu_debugfs_base_dir; + struct dentry *fpuemu_debugfs_inst_dir; + char name[32]; + + fpuemu_debugfs_base_dir = debugfs_create_dir("fpuemustats", + mips_debugfs_dir); + + debugfs_create_file("fpuemustats_clear", 0444, mips_debugfs_dir, NULL, + &fpuemustats_clear_fops); + +#define FPU_EMU_STAT_OFFSET(m) \ + offsetof(struct mips_fpu_emulator_stats, m) + +#define FPU_STAT_CREATE(m) \ +do { \ + debugfs_create_file(#m, 0444, fpuemu_debugfs_base_dir, \ + (void *)FPU_EMU_STAT_OFFSET(m), \ + &fops_fpuemu_stat); \ +} while (0) + + FPU_STAT_CREATE(emulated); + FPU_STAT_CREATE(loads); + FPU_STAT_CREATE(stores); + FPU_STAT_CREATE(branches); + FPU_STAT_CREATE(cp1ops); + FPU_STAT_CREATE(cp1xops); + FPU_STAT_CREATE(errors); + FPU_STAT_CREATE(ieee754_inexact); + FPU_STAT_CREATE(ieee754_underflow); + FPU_STAT_CREATE(ieee754_overflow); + FPU_STAT_CREATE(ieee754_zerodiv); + FPU_STAT_CREATE(ieee754_invalidop); + FPU_STAT_CREATE(ds_emul); + + fpuemu_debugfs_inst_dir = debugfs_create_dir("instructions", + fpuemu_debugfs_base_dir); + +#define FPU_STAT_CREATE_EX(m) \ +do { \ + adjust_instruction_counter_name(name, #m, sizeof(name)); \ + \ + debugfs_create_file(name, 0444, fpuemu_debugfs_inst_dir, \ + (void *)FPU_EMU_STAT_OFFSET(m), \ + &fops_fpuemu_stat); \ +} while (0) + + FPU_STAT_CREATE_EX(abs_s); + FPU_STAT_CREATE_EX(abs_d); + FPU_STAT_CREATE_EX(add_s); + FPU_STAT_CREATE_EX(add_d); + FPU_STAT_CREATE_EX(bc1eqz); + FPU_STAT_CREATE_EX(bc1nez); + FPU_STAT_CREATE_EX(ceil_w_s); + FPU_STAT_CREATE_EX(ceil_w_d); + FPU_STAT_CREATE_EX(ceil_l_s); + FPU_STAT_CREATE_EX(ceil_l_d); + FPU_STAT_CREATE_EX(class_s); + FPU_STAT_CREATE_EX(class_d); + FPU_STAT_CREATE_EX(cmp_af_s); + FPU_STAT_CREATE_EX(cmp_af_d); + FPU_STAT_CREATE_EX(cmp_eq_s); + FPU_STAT_CREATE_EX(cmp_eq_d); + FPU_STAT_CREATE_EX(cmp_le_s); + FPU_STAT_CREATE_EX(cmp_le_d); + FPU_STAT_CREATE_EX(cmp_lt_s); + FPU_STAT_CREATE_EX(cmp_lt_d); + FPU_STAT_CREATE_EX(cmp_ne_s); + FPU_STAT_CREATE_EX(cmp_ne_d); + FPU_STAT_CREATE_EX(cmp_or_s); + FPU_STAT_CREATE_EX(cmp_or_d); + FPU_STAT_CREATE_EX(cmp_ueq_s); + FPU_STAT_CREATE_EX(cmp_ueq_d); + FPU_STAT_CREATE_EX(cmp_ule_s); + FPU_STAT_CREATE_EX(cmp_ule_d); + FPU_STAT_CREATE_EX(cmp_ult_s); + FPU_STAT_CREATE_EX(cmp_ult_d); + FPU_STAT_CREATE_EX(cmp_un_s); + FPU_STAT_CREATE_EX(cmp_un_d); + FPU_STAT_CREATE_EX(cmp_une_s); + FPU_STAT_CREATE_EX(cmp_une_d); + FPU_STAT_CREATE_EX(cmp_saf_s); + FPU_STAT_CREATE_EX(cmp_saf_d); + FPU_STAT_CREATE_EX(cmp_seq_s); + FPU_STAT_CREATE_EX(cmp_seq_d); + FPU_STAT_CREATE_EX(cmp_sle_s); + FPU_STAT_CREATE_EX(cmp_sle_d); + FPU_STAT_CREATE_EX(cmp_slt_s); + FPU_STAT_CREATE_EX(cmp_slt_d); + FPU_STAT_CREATE_EX(cmp_sne_s); + FPU_STAT_CREATE_EX(cmp_sne_d); + FPU_STAT_CREATE_EX(cmp_sor_s); + FPU_STAT_CREATE_EX(cmp_sor_d); + FPU_STAT_CREATE_EX(cmp_sueq_s); + FPU_STAT_CREATE_EX(cmp_sueq_d); + FPU_STAT_CREATE_EX(cmp_sule_s); + FPU_STAT_CREATE_EX(cmp_sule_d); + FPU_STAT_CREATE_EX(cmp_sult_s); + FPU_STAT_CREATE_EX(cmp_sult_d); + FPU_STAT_CREATE_EX(cmp_sun_s); + FPU_STAT_CREATE_EX(cmp_sun_d); + FPU_STAT_CREATE_EX(cmp_sune_s); + FPU_STAT_CREATE_EX(cmp_sune_d); + FPU_STAT_CREATE_EX(cvt_d_l); + FPU_STAT_CREATE_EX(cvt_d_s); + FPU_STAT_CREATE_EX(cvt_d_w); + FPU_STAT_CREATE_EX(cvt_l_s); + FPU_STAT_CREATE_EX(cvt_l_d); + FPU_STAT_CREATE_EX(cvt_s_d); + FPU_STAT_CREATE_EX(cvt_s_l); + FPU_STAT_CREATE_EX(cvt_s_w); + FPU_STAT_CREATE_EX(cvt_w_s); + FPU_STAT_CREATE_EX(cvt_w_d); + FPU_STAT_CREATE_EX(div_s); + FPU_STAT_CREATE_EX(div_d); + FPU_STAT_CREATE_EX(floor_w_s); + FPU_STAT_CREATE_EX(floor_w_d); + FPU_STAT_CREATE_EX(floor_l_s); + FPU_STAT_CREATE_EX(floor_l_d); + FPU_STAT_CREATE_EX(maddf_s); + FPU_STAT_CREATE_EX(maddf_d); + FPU_STAT_CREATE_EX(max_s); + FPU_STAT_CREATE_EX(max_d); + FPU_STAT_CREATE_EX(maxa_s); + FPU_STAT_CREATE_EX(maxa_d); + FPU_STAT_CREATE_EX(min_s); + FPU_STAT_CREATE_EX(min_d); + FPU_STAT_CREATE_EX(mina_s); + FPU_STAT_CREATE_EX(mina_d); + FPU_STAT_CREATE_EX(mov_s); + FPU_STAT_CREATE_EX(mov_d); + FPU_STAT_CREATE_EX(msubf_s); + FPU_STAT_CREATE_EX(msubf_d); + FPU_STAT_CREATE_EX(mul_s); + FPU_STAT_CREATE_EX(mul_d); + FPU_STAT_CREATE_EX(neg_s); + FPU_STAT_CREATE_EX(neg_d); + FPU_STAT_CREATE_EX(recip_s); + FPU_STAT_CREATE_EX(recip_d); + FPU_STAT_CREATE_EX(rint_s); + FPU_STAT_CREATE_EX(rint_d); + FPU_STAT_CREATE_EX(round_w_s); + FPU_STAT_CREATE_EX(round_w_d); + FPU_STAT_CREATE_EX(round_l_s); + FPU_STAT_CREATE_EX(round_l_d); + FPU_STAT_CREATE_EX(rsqrt_s); + FPU_STAT_CREATE_EX(rsqrt_d); + FPU_STAT_CREATE_EX(sel_s); + FPU_STAT_CREATE_EX(sel_d); + FPU_STAT_CREATE_EX(seleqz_s); + FPU_STAT_CREATE_EX(seleqz_d); + FPU_STAT_CREATE_EX(selnez_s); + FPU_STAT_CREATE_EX(selnez_d); + FPU_STAT_CREATE_EX(sqrt_s); + FPU_STAT_CREATE_EX(sqrt_d); + FPU_STAT_CREATE_EX(sub_s); + FPU_STAT_CREATE_EX(sub_d); + FPU_STAT_CREATE_EX(trunc_w_s); + FPU_STAT_CREATE_EX(trunc_w_d); + FPU_STAT_CREATE_EX(trunc_l_s); + FPU_STAT_CREATE_EX(trunc_l_d); + + return 0; +} +arch_initcall(debugfs_fpuemu); -- cgit v1.3.1