linux-user/i386/cpu_loop.c | 9 +++++++++ linux-user/main.c | 7 +++++++ 2 files changed, 16 insertions(+)
On linux user mode, CPUX86State::gdt::base from Different CPUX86State Objects have same value, It is incorrect! Every CPUX86State::gdt::base Must points to independent memory space.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1405
Signed-off-by: fanwenjie <fanwj@mail.ustc.edu.cn>
---
linux-user/i386/cpu_loop.c | 9 +++++++++
linux-user/main.c | 7 +++++++
2 files changed, 16 insertions(+)
diff --git a/linux-user/i386/cpu_loop.c b/linux-user/i386/cpu_loop.c
index 865413c..48511cd 100644
--- a/linux-user/i386/cpu_loop.c
+++ b/linux-user/i386/cpu_loop.c
@@ -314,8 +314,17 @@ void cpu_loop(CPUX86State *env)
}
}
+static void target_cpu_free(void *obj)
+{
+ CPUArchState* env = ((CPUState*)obj)->env_ptr;
+ target_munmap(env->gdt.base, sizeof(uint64_t) * TARGET_GDT_ENTRIES);
+ g_free(obj);
+}
+
void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
{
+ CPUState* cpu = env_cpu(env);
+ OBJECT(cpu)->free = target_cpu_free;
env->cr[0] = CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK;
env->hflags |= HF_PE_MASK | HF_CPL_MASK;
if (env->features[FEAT_1_EDX] & CPUID_SSE) {
diff --git a/linux-user/main.c b/linux-user/main.c
index a17fed0..3acd9b4 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -234,6 +234,13 @@ CPUArchState *cpu_copy(CPUArchState *env)
new_cpu->tcg_cflags = cpu->tcg_cflags;
memcpy(new_env, env, sizeof(CPUArchState));
+#if defined(TARGET_I386) || defined(TARGET_X86_64)
+ new_env->gdt.base = target_mmap(0, sizeof(uint64_t) * TARGET_GDT_ENTRIES,
+ PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ memcpy((void*)g2h_untagged(new_env->gdt.base), (void*)g2h_untagged(env->gdt.base), sizeof(uint64_t) * TARGET_GDT_ENTRIES);
+ OBJECT(new_cpu)->free = OBJECT(cpu)->free;
+#endif
/* Clone all break/watchpoints.
Note: Once we support ptrace with hw-debug register access, make sure
--
2.34.1
Le 08/02/2023 à 16:49, fanwj@mail.ustc.edu.cn a écrit : > On linux user mode, CPUX86State::gdt::base from Different CPUX86State Objects have same value, It is incorrect! Every CPUX86State::gdt::base Must points to independent memory space. > > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1405 > Signed-off-by: fanwenjie <fanwj@mail.ustc.edu.cn> > --- > linux-user/i386/cpu_loop.c | 9 +++++++++ > linux-user/main.c | 7 +++++++ > 2 files changed, 16 insertions(+) > > diff --git a/linux-user/i386/cpu_loop.c b/linux-user/i386/cpu_loop.c > index 865413c..48511cd 100644 > --- a/linux-user/i386/cpu_loop.c > +++ b/linux-user/i386/cpu_loop.c > @@ -314,8 +314,17 @@ void cpu_loop(CPUX86State *env) > } > } > > +static void target_cpu_free(void *obj) > +{ > + CPUArchState* env = ((CPUState*)obj)->env_ptr; > + target_munmap(env->gdt.base, sizeof(uint64_t) * TARGET_GDT_ENTRIES); > + g_free(obj); > +} > + > void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs) > { > + CPUState* cpu = env_cpu(env); > + OBJECT(cpu)->free = target_cpu_free; > env->cr[0] = CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK; > env->hflags |= HF_PE_MASK | HF_CPL_MASK; > if (env->features[FEAT_1_EDX] & CPUID_SSE) { > diff --git a/linux-user/main.c b/linux-user/main.c > index a17fed0..3acd9b4 100644 > --- a/linux-user/main.c > +++ b/linux-user/main.c > @@ -234,6 +234,13 @@ CPUArchState *cpu_copy(CPUArchState *env) > > new_cpu->tcg_cflags = cpu->tcg_cflags; > memcpy(new_env, env, sizeof(CPUArchState)); > +#if defined(TARGET_I386) || defined(TARGET_X86_64) > + new_env->gdt.base = target_mmap(0, sizeof(uint64_t) * TARGET_GDT_ENTRIES, > + PROT_READ|PROT_WRITE, > + MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); > + memcpy((void*)g2h_untagged(new_env->gdt.base), (void*)g2h_untagged(env->gdt.base), sizeof(uint64_t) * TARGET_GDT_ENTRIES); > + OBJECT(new_cpu)->free = OBJECT(cpu)->free; > +#endif > > /* Clone all break/watchpoints. > Note: Once we support ptrace with hw-debug register access, make sure Applied to my linux-user-for-8.0 branch. Thanks, Laurent
Richard, do you think it's correct? Thanks, Laurent Le 08/02/2023 à 16:49, fanwj@mail.ustc.edu.cn a écrit : > On linux user mode, CPUX86State::gdt::base from Different CPUX86State Objects have same value, It is incorrect! Every CPUX86State::gdt::base Must points to independent memory space. > > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1405 > Signed-off-by: fanwenjie <fanwj@mail.ustc.edu.cn> > --- > linux-user/i386/cpu_loop.c | 9 +++++++++ > linux-user/main.c | 7 +++++++ > 2 files changed, 16 insertions(+) > > diff --git a/linux-user/i386/cpu_loop.c b/linux-user/i386/cpu_loop.c > index 865413c..48511cd 100644 > --- a/linux-user/i386/cpu_loop.c > +++ b/linux-user/i386/cpu_loop.c > @@ -314,8 +314,17 @@ void cpu_loop(CPUX86State *env) > } > } > > +static void target_cpu_free(void *obj) > +{ > + CPUArchState* env = ((CPUState*)obj)->env_ptr; > + target_munmap(env->gdt.base, sizeof(uint64_t) * TARGET_GDT_ENTRIES); > + g_free(obj); > +} > + > void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs) > { > + CPUState* cpu = env_cpu(env); > + OBJECT(cpu)->free = target_cpu_free; > env->cr[0] = CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK; > env->hflags |= HF_PE_MASK | HF_CPL_MASK; > if (env->features[FEAT_1_EDX] & CPUID_SSE) { > diff --git a/linux-user/main.c b/linux-user/main.c > index a17fed0..3acd9b4 100644 > --- a/linux-user/main.c > +++ b/linux-user/main.c > @@ -234,6 +234,13 @@ CPUArchState *cpu_copy(CPUArchState *env) > > new_cpu->tcg_cflags = cpu->tcg_cflags; > memcpy(new_env, env, sizeof(CPUArchState)); > +#if defined(TARGET_I386) || defined(TARGET_X86_64) > + new_env->gdt.base = target_mmap(0, sizeof(uint64_t) * TARGET_GDT_ENTRIES, > + PROT_READ|PROT_WRITE, > + MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); > + memcpy((void*)g2h_untagged(new_env->gdt.base), (void*)g2h_untagged(env->gdt.base), sizeof(uint64_t) * TARGET_GDT_ENTRIES); > + OBJECT(new_cpu)->free = OBJECT(cpu)->free; > +#endif > > /* Clone all break/watchpoints. > Note: Once we support ptrace with hw-debug register access, make sure
On 3/7/23 06:30, Laurent Vivier wrote: > Richard, > > do you think it's correct? It's correct enough, until target/i386 is fixed to not require the GDT/LDT to be incorrectly mapped in the (ring 3) user address space. You may wish to fix a few nits when applying: >> } >> +static void target_cpu_free(void *obj) Missing line before function. >> +#if defined(TARGET_I386) || defined(TARGET_X86_64) >> + new_env->gdt.base = target_mmap(0, sizeof(uint64_t) * TARGET_GDT_ENTRIES, >> + PROT_READ|PROT_WRITE, >> + MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); >> + memcpy((void*)g2h_untagged(new_env->gdt.base), (void*)g2h_untagged(env->gdt.base), >> sizeof(uint64_t) * TARGET_GDT_ENTRIES); Unnecessary casts, overlong line. r~
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