print kernel stacktrace for exceptions in kernel

fpu alignment check feature, checksum feature

diff --git a/common/include/arch/i386/archtypes.h b/common/include/arch/i386/archtypes.h
index fb424c977364590137af96bb856864b31557cbed..e16f778013e6d55da304a58dae172ec51c42466e 100644 (file)
--- a/common/include/arch/i386/archtypes.h
+++ b/common/include/arch/i386/archtypes.h
@@ -37,6 +37,7 @@ struct fpu_state_s {
        /* fpu_image includes 512 bytes of image itself and
         * additional 15 bytes required for manual 16-byte alignment. */
        char fpu_image[527];
+       u32_t checksum;
 };
 
 #define INMEMORY(p) (!p->p_seg.p_cr3 || get_cpulocal_var(ptproc) == p)

diff --git a/kernel/Makefile b/kernel/Makefile
index deb33e353ea8963849f2b95e80653a57118535f2..bbc4cb6ccbb84da81f685c7f99082150cc920b78 100644 (file)
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -14,7 +14,7 @@ SRCS += smp.c
 .endif
 
 DPADD+=        ${LIBTIMERS} ${LIBSYS} ${LIBEXEC}
-LDADD+=        -ltimers -lsys -lexec
+LDADD+=        -ltimers -lsys -lexec -lz
 
 CFLAGS += -D__kernel__
 

diff --git a/kernel/arch/i386/arch_system.c b/kernel/arch/i386/arch_system.c
index 2c32b82c65cc3adaa82ec12b7360ca6436edae04..a7f230573d2598fc24206d14db8baa578721e37e 100644 (file)
--- a/kernel/arch/i386/arch_system.c
+++ b/kernel/arch/i386/arch_system.c
@@ -58,6 +58,27 @@ FORWARD _PROTOTYPE( void ser_dump_proc_cpu, (void));
 FORWARD _PROTOTYPE( void ser_init, (void));
 #endif
 
+PRIVATE u32_t fpusum(struct proc *p)
+{
+       void *save_area = p->p_fpu_state.fpu_save_area_p;
+       return crc32(0, save_area, FPU_XFP_SIZE);
+}
+
+PUBLIC void fpu_makechecksum(struct proc *p)
+{
+       p->p_fpu_state.checksum = fpusum(p);
+}
+
+PUBLIC void fpu_verifychecksum(struct proc *p)
+{
+       static int n;
+       n++;
+       if(p->p_fpu_state.checksum != fpusum(p)) {
+               printf("%d / %s fpu state broken!", p->p_endpoint, p->p_name);
+               util_stacktrace();
+       }
+}
+
 PUBLIC __dead void arch_monitor(void)
 {
        monitor();
@@ -252,16 +273,23 @@ PUBLIC void fpu_init(void)
 
 PUBLIC void save_local_fpu(struct proc *pr)
 {
+       static int n;
+       phys_bytes save_area = (phys_bytes) pr->p_fpu_state.fpu_save_area_p;
        if(!is_fpu())
                return;
 
+       /* save area must be 16-byte aligned */
+       assert(!(save_area % FPUALIGN));
+
        /* Save changed FPU context. */
        if(osfxsr_feature) {
-               fxsave(pr->p_fpu_state.fpu_save_area_p);
+               fxsave(save_area);
                fninit();
        } else {
-               fnsave(pr->p_fpu_state.fpu_save_area_p);
+               fnsave(save_area);
        }
+
+       fpu_makechecksum(pr);
 }
 
 PUBLIC void save_fpu(struct proc *pr)
@@ -304,10 +332,14 @@ PUBLIC void restore_fpu(struct proc *pr)
                fninit();
                pr->p_misc_flags |= MF_FPU_INITIALIZED;
        } else {
+               phys_bytes save_area = (phys_bytes) pr->p_fpu_state.fpu_save_area_p;
+               /* save area must be 16-byte aligned */
+               assert(!(save_area % FPUALIGN));
+               fpu_verifychecksum(pr);
                if(osfxsr_feature) {
-                       fxrstor(pr->p_fpu_state.fpu_save_area_p);
+                       fxrstor(save_area);
                } else {
-                       frstor(pr->p_fpu_state.fpu_save_area_p);
+                       frstor(save_area);
                }
        }
 }

diff --git a/kernel/arch/i386/include/arch_proto.h b/kernel/arch/i386/include/arch_proto.h
index af605c6ed2e7ed0df0143eade6eb3084e542887e..fb5666123cd59d457fe167a9d644e960b7943cff 100644 (file)
--- a/kernel/arch/i386/include/arch_proto.h
+++ b/kernel/arch/i386/include/arch_proto.h
@@ -95,10 +95,10 @@ _PROTOTYPE( void ia32_msr_read, (u32_t reg, u32_t * hi, u32_t * lo) );
 _PROTOTYPE( void ia32_msr_write, (u32_t reg, u32_t hi, u32_t lo)       );
 _PROTOTYPE( void fninit, (void));
 _PROTOTYPE( void clts, (void));
-_PROTOTYPE( void fxsave, (void *));
-_PROTOTYPE( void fnsave, (void *));
-_PROTOTYPE( void fxrstor, (void *));
-_PROTOTYPE( void frstor, (void *));
+_PROTOTYPE( void fxsave, (vir_bytes));
+_PROTOTYPE( void fnsave, (vir_bytes));
+_PROTOTYPE( void fxrstor, (vir_bytes));
+_PROTOTYPE( void frstor, (vir_bytes));
 _PROTOTYPE( unsigned short fnstsw, (void));
 _PROTOTYPE( void fnstcw, (unsigned short* cw));
 

diff --git a/kernel/arch/i386/sconst.h b/kernel/arch/i386/sconst.h
index 5f2bd6e0996966b19020910d8872c6ae19d3ac51..d48640b6dc29da4f535513902429b6f92461c95c 100644 (file)
--- a/kernel/arch/i386/sconst.h
+++ b/kernel/arch/i386/sconst.h
@@ -28,7 +28,7 @@
        SSREG = SPREG+W
        P_STACKTOP = SSREG+W
        FP_SAVE_AREA_P = P_STACKTOP
-       P_LDT_SEL = FP_SAVE_AREA_P + 532
+       P_LDT_SEL = FP_SAVE_AREA_P + 536
        P_CR3 = P_LDT_SEL+W
        P_CR3_V = P_CR3+4
        P_LDT = P_CR3_V+W

diff --git a/kernel/debug.h b/kernel/debug.h
index ce808f31ac4d894e0218f7186d4a1f5f97178eb7..fc422e62cc3e51672f3b5d0a2dd150c9998f7032 100644 (file)
--- a/kernel/debug.h
+++ b/kernel/debug.h
@@ -37,6 +37,8 @@
  */
 #define DEBUG_RACE                     0
 
+#define DEBUG_FPUCHECK                 1
+
 /* DEBUG_DUMPIPC dumps all IPC to serial; due to the amount of logging it is 
  * strongly recommended to set "ctty 0" in the boot monitor and run inside a 
  * virtual machine if you enable this; on the hardware it would take forever 

diff --git a/kernel/proc.c b/kernel/proc.c
index b8cf5cf99683f440935af62eea698917d112d4d0..820bda02d6b360f10ab6add03989600d62169345 100644 (file)
--- a/kernel/proc.c
+++ b/kernel/proc.c
@@ -257,6 +257,10 @@ PUBLIC void switch_to_user(void)
        int tlb_must_refresh = 0;
 #endif
 
+       char buf[100];
+       u32_t c;
+       c = crc32(0, buf, 100);
+
        p = get_cpulocal_var(proc_ptr);
        /*
         * if the current process is still runnable check the misc flags and let

diff --git a/kernel/proto.h b/kernel/proto.h
index 3aae90a346719720beb1686e479db26b02f883bc..9d1090d369d46b85102dc07e6aed8c7be823d5f2 100644 (file)
--- a/kernel/proto.h
+++ b/kernel/proto.h
@@ -223,6 +223,9 @@ _PROTOTYPE( int copy_msg_to_user, (struct proc * p, message * src,
 _PROTOTYPE(void switch_address_space, (struct proc * p));
 _PROTOTYPE(void release_address_space, (struct proc *pr));
 
+_PROTOTYPE(void fpu_makechecksum, (struct proc *p));
+_PROTOTYPE(void fpu_verifychecksum, (struct proc *p));
+
 _PROTOTYPE(void enable_fpu_exception, (void));
 _PROTOTYPE(void disable_fpu_exception, (void));
 _PROTOTYPE(void release_fpu, (struct proc * p));

diff --git a/kernel/system/do_fork.c b/kernel/system/do_fork.c
index 0b62361963ecc564ec6baff326537e1cb42e3eec..f2576843b7ce30e079baf07331c51ff785258df3 100644 (file)
--- a/kernel/system/do_fork.c
+++ b/kernel/system/do_fork.c
@@ -65,10 +65,13 @@ PUBLIC int do_fork(struct proc * caller, message * m_ptr)
 #if (_MINIX_CHIP == _CHIP_INTEL)
   rpc->p_seg.p_ldt_sel = old_ldt_sel;  /* restore descriptors */
   rpc->p_fpu_state.fpu_save_area_p = old_fpu_save_area_p;
-  if(proc_used_fpu(rpp))
+  if(proc_used_fpu(rpp)) {
+       fpu_verifychecksum(rpp);
        memcpy(rpc->p_fpu_state.fpu_save_area_p,
               rpp->p_fpu_state.fpu_save_area_p,
               FPU_XFP_SIZE);
+       fpu_verifychecksum(rpc);
+  }
 #endif
   if(++gen >= _ENDPOINT_MAX_GENERATION)        /* increase generation */
        gen = 1;                        /* generation number wraparound */

diff --git a/kernel/system/do_mcontext.c b/kernel/system/do_mcontext.c
index c105acf5eb0cb59f96409e69a02274f8dfc46944..4bfc8ff94a00c628907ac634c980aaaf6e49d35a 100644 (file)
--- a/kernel/system/do_mcontext.c
+++ b/kernel/system/do_mcontext.c
@@ -86,6 +86,7 @@ PUBLIC int do_setmcontext(struct proc * caller, message * m_ptr)
        rp->p_misc_flags |= MF_FPU_INITIALIZED;
        memcpy(rp->p_fpu_state.fpu_save_area_p, &(mc.mc_fpu_state),
                                                                FPU_XFP_SIZE);
+       fpu_makechecksum(rp);
   } else
        rp->p_misc_flags &= ~MF_FPU_INITIALIZED;
   /* force reloading FPU in either case */

diff --git a/kernel/system/do_sigreturn.c b/kernel/system/do_sigreturn.c
index 592c8e2a2135b41c170fb76547ce2d612604229d..e8a5232ba67b7938f6625b141b44c7bee400e1f4 100644 (file)
--- a/kernel/system/do_sigreturn.c
+++ b/kernel/system/do_sigreturn.c
@@ -56,8 +56,10 @@ PUBLIC int do_sigreturn(struct proc * caller, message * m_ptr)
 #if (_MINIX_CHIP == _CHIP_INTEL)
   if(sc.sc_flags & MF_FPU_INITIALIZED)
   {
+       fpu_verifychecksum(rp);
        memcpy(rp->p_fpu_state.fpu_save_area_p, &sc.sc_fpu_state,
                FPU_XFP_SIZE);
+       fpu_makechecksum(rp);
        rp->p_misc_flags |=  MF_FPU_INITIALIZED; /* Restore math usage flag. */
        /* force reloading FPU */
        release_fpu(rp);