Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

[linux-drm-fsl-dcu.git] / arch / mips / kernel / elf.c

diff --git a/arch/mips/kernel/elf.c b/arch/mips/kernel/elf.c
index 4a4d9e067c89427fc34e990586f0e8237a9418ba..c3c234dc0c07748ad7696f7b4d3c395df3954293 100644 (file)
--- a/arch/mips/kernel/elf.c
+++ b/arch/mips/kernel/elf.c
@@ -11,6 +11,12 @@
 #include <linux/elf.h>
 #include <linux/sched.h>
 
+#include <asm/cpu-info.h>
+
+/* Whether to accept legacy-NaN and 2008-NaN user binaries.  */
+bool mips_use_nan_legacy;
+bool mips_use_nan_2008;
+
 /* FPU modes */
 enum {
        FP_FRE,
@@ -68,15 +74,23 @@ static struct mode_req none_req = { true, true, false, true, true };
 int arch_elf_pt_proc(void *_ehdr, void *_phdr, struct file *elf,
                     bool is_interp, struct arch_elf_state *state)
 {
-       struct elf32_hdr *ehdr32 = _ehdr;
+       union {
+               struct elf32_hdr e32;
+               struct elf64_hdr e64;
+       } *ehdr = _ehdr;
        struct elf32_phdr *phdr32 = _phdr;
        struct elf64_phdr *phdr64 = _phdr;
        struct mips_elf_abiflags_v0 abiflags;
+       bool elf32;
+       u32 flags;
        int ret;
 
+       elf32 = ehdr->e32.e_ident[EI_CLASS] == ELFCLASS32;
+       flags = elf32 ? ehdr->e32.e_flags : ehdr->e64.e_flags;
+
        /* Lets see if this is an O32 ELF */
-       if (ehdr32->e_ident[EI_CLASS] == ELFCLASS32) {
-               if (ehdr32->e_flags & EF_MIPS_FP64) {
+       if (elf32) {
+               if (flags & EF_MIPS_FP64) {
                        /*
                         * Set MIPS_ABI_FP_OLD_64 for EF_MIPS_FP64. We will override it
                         * later if needed
@@ -120,13 +134,50 @@ int arch_elf_pt_proc(void *_ehdr, void *_phdr, struct file *elf,
        return 0;
 }
 
-int arch_check_elf(void *_ehdr, bool has_interpreter,
+int arch_check_elf(void *_ehdr, bool has_interpreter, void *_interp_ehdr,
                   struct arch_elf_state *state)
 {
-       struct elf32_hdr *ehdr = _ehdr;
+       union {
+               struct elf32_hdr e32;
+               struct elf64_hdr e64;
+       } *ehdr = _ehdr;
+       union {
+               struct elf32_hdr e32;
+               struct elf64_hdr e64;
+       } *iehdr = _interp_ehdr;
        struct mode_req prog_req, interp_req;
        int fp_abi, interp_fp_abi, abi0, abi1, max_abi;
-       bool is_mips64;
+       bool elf32;
+       u32 flags;
+
+       elf32 = ehdr->e32.e_ident[EI_CLASS] == ELFCLASS32;
+       flags = elf32 ? ehdr->e32.e_flags : ehdr->e64.e_flags;
+
+       /*
+        * Determine the NaN personality, reject the binary if not allowed.
+        * Also ensure that any interpreter matches the executable.
+        */
+       if (flags & EF_MIPS_NAN2008) {
+               if (mips_use_nan_2008)
+                       state->nan_2008 = 1;
+               else
+                       return -ENOEXEC;
+       } else {
+               if (mips_use_nan_legacy)
+                       state->nan_2008 = 0;
+               else
+                       return -ENOEXEC;
+       }
+       if (has_interpreter) {
+               bool ielf32;
+               u32 iflags;
+
+               ielf32 = iehdr->e32.e_ident[EI_CLASS] == ELFCLASS32;
+               iflags = ielf32 ? iehdr->e32.e_flags : iehdr->e64.e_flags;
+
+               if ((flags ^ iflags) & EF_MIPS_NAN2008)
+                       return -ELIBBAD;
+       }
 
        if (!config_enabled(CONFIG_MIPS_O32_FP64_SUPPORT))
                return 0;
@@ -142,21 +193,18 @@ int arch_check_elf(void *_ehdr, bool has_interpreter,
                abi0 = abi1 = fp_abi;
        }
 
-       is_mips64 = (ehdr->e_ident[EI_CLASS] == ELFCLASS64) ||
-                   (ehdr->e_flags & EF_MIPS_ABI2);
+       if (elf32 && !(flags & EF_MIPS_ABI2)) {
+               /* Default to a mode capable of running code expecting FR=0 */
+               state->overall_fp_mode = cpu_has_mips_r6 ? FP_FRE : FP_FR0;
 
-       if (is_mips64) {
+               /* Allow all ABIs we know about */
+               max_abi = MIPS_ABI_FP_64A;
+       } else {
                /* MIPS64 code always uses FR=1, thus the default is easy */
                state->overall_fp_mode = FP_FR1;
 
                /* Disallow access to the various FPXX & FP64 ABIs */
                max_abi = MIPS_ABI_FP_SOFT;
-       } else {
-               /* Default to a mode capable of running code expecting FR=0 */
-               state->overall_fp_mode = cpu_has_mips_r6 ? FP_FRE : FP_FR0;
-
-               /* Allow all ABIs we know about */
-               max_abi = MIPS_ABI_FP_64A;
        }
 
        if ((abi0 > max_abi && abi0 != MIPS_ABI_FP_UNKNOWN) ||
@@ -254,3 +302,27 @@ void mips_set_personality_fp(struct arch_elf_state *state)
                BUG();
        }
 }
+
+/*
+ * Select the IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode
+ * in FCSR according to the ELF NaN personality.
+ */
+void mips_set_personality_nan(struct arch_elf_state *state)
+{
+       struct cpuinfo_mips *c = &boot_cpu_data;
+       struct task_struct *t = current;
+
+       t->thread.fpu.fcr31 = c->fpu_csr31;
+       switch (state->nan_2008) {
+       case 0:
+               break;
+       case 1:
+               if (!(c->fpu_msk31 & FPU_CSR_NAN2008))
+                       t->thread.fpu.fcr31 |= FPU_CSR_NAN2008;
+               if (!(c->fpu_msk31 & FPU_CSR_ABS2008))
+                       t->thread.fpu.fcr31 |= FPU_CSR_ABS2008;
+               break;
+       default:
+               BUG();
+       }
+}