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commit b26b2b24b1d8cc6e24d81872e6e18c0d76382a81
parent 121b018f8c74b4e0ba81b4b8ee73a82db3f24b7b
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 28 Nov 2018 12:51:10 -0800

Merge tag 'xtensa-20181128' of git://github.com/jcmvbkbc/linux-xtensa

Pull Xtensa fixes from Max Filippov:

 - fix kernel exception on userspace access to a currently disabled
   coprocessor

 - fix coprocessor data saving/restoring in configurations with multiple
   coprocessors

 - fix ptrace access to coprocessor data on configurations with multiple
   coprocessors with high alignment requirements

* tag 'xtensa-20181128' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: fix coprocessor part of ptrace_{get,set}xregs
  xtensa: fix coprocessor context offset definitions
  xtensa: enable coprocessors that are being flushed

Diffstat:
March/xtensa/kernel/asm-offsets.c | 16++++++++--------
March/xtensa/kernel/process.c | 5++++-
March/xtensa/kernel/ptrace.c | 42++++++++++++++++++++++++++++++++++++++----
3 files changed, 50 insertions(+), 13 deletions(-)

diff --git a/arch/xtensa/kernel/asm-offsets.c b/arch/xtensa/kernel/asm-offsets.c @@ -94,14 +94,14 @@ int main(void) DEFINE(THREAD_SP, offsetof (struct task_struct, thread.sp)); DEFINE(THREAD_CPENABLE, offsetof (struct thread_info, cpenable)); #if XTENSA_HAVE_COPROCESSORS - DEFINE(THREAD_XTREGS_CP0, offsetof (struct thread_info, xtregs_cp)); - DEFINE(THREAD_XTREGS_CP1, offsetof (struct thread_info, xtregs_cp)); - DEFINE(THREAD_XTREGS_CP2, offsetof (struct thread_info, xtregs_cp)); - DEFINE(THREAD_XTREGS_CP3, offsetof (struct thread_info, xtregs_cp)); - DEFINE(THREAD_XTREGS_CP4, offsetof (struct thread_info, xtregs_cp)); - DEFINE(THREAD_XTREGS_CP5, offsetof (struct thread_info, xtregs_cp)); - DEFINE(THREAD_XTREGS_CP6, offsetof (struct thread_info, xtregs_cp)); - DEFINE(THREAD_XTREGS_CP7, offsetof (struct thread_info, xtregs_cp)); + DEFINE(THREAD_XTREGS_CP0, offsetof(struct thread_info, xtregs_cp.cp0)); + DEFINE(THREAD_XTREGS_CP1, offsetof(struct thread_info, xtregs_cp.cp1)); + DEFINE(THREAD_XTREGS_CP2, offsetof(struct thread_info, xtregs_cp.cp2)); + DEFINE(THREAD_XTREGS_CP3, offsetof(struct thread_info, xtregs_cp.cp3)); + DEFINE(THREAD_XTREGS_CP4, offsetof(struct thread_info, xtregs_cp.cp4)); + DEFINE(THREAD_XTREGS_CP5, offsetof(struct thread_info, xtregs_cp.cp5)); + DEFINE(THREAD_XTREGS_CP6, offsetof(struct thread_info, xtregs_cp.cp6)); + DEFINE(THREAD_XTREGS_CP7, offsetof(struct thread_info, xtregs_cp.cp7)); #endif DEFINE(THREAD_XTREGS_USER, offsetof (struct thread_info, xtregs_user)); DEFINE(XTREGS_USER_SIZE, sizeof(xtregs_user_t)); diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c @@ -94,18 +94,21 @@ void coprocessor_release_all(struct thread_info *ti) void coprocessor_flush_all(struct thread_info *ti) { - unsigned long cpenable; + unsigned long cpenable, old_cpenable; int i; preempt_disable(); + RSR_CPENABLE(old_cpenable); cpenable = ti->cpenable; + WSR_CPENABLE(cpenable); for (i = 0; i < XCHAL_CP_MAX; i++) { if ((cpenable & 1) != 0 && coprocessor_owner[i] == ti) coprocessor_flush(ti, i); cpenable >>= 1; } + WSR_CPENABLE(old_cpenable); preempt_enable(); } diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c @@ -127,12 +127,37 @@ static int ptrace_setregs(struct task_struct *child, void __user *uregs) } +#if XTENSA_HAVE_COPROCESSORS +#define CP_OFFSETS(cp) \ + { \ + .elf_xtregs_offset = offsetof(elf_xtregs_t, cp), \ + .ti_offset = offsetof(struct thread_info, xtregs_cp.cp), \ + .sz = sizeof(xtregs_ ## cp ## _t), \ + } + +static const struct { + size_t elf_xtregs_offset; + size_t ti_offset; + size_t sz; +} cp_offsets[] = { + CP_OFFSETS(cp0), + CP_OFFSETS(cp1), + CP_OFFSETS(cp2), + CP_OFFSETS(cp3), + CP_OFFSETS(cp4), + CP_OFFSETS(cp5), + CP_OFFSETS(cp6), + CP_OFFSETS(cp7), +}; +#endif + static int ptrace_getxregs(struct task_struct *child, void __user *uregs) { struct pt_regs *regs = task_pt_regs(child); struct thread_info *ti = task_thread_info(child); elf_xtregs_t __user *xtregs = uregs; int ret = 0; + int i __maybe_unused; if (!access_ok(VERIFY_WRITE, uregs, sizeof(elf_xtregs_t))) return -EIO; @@ -140,8 +165,13 @@ static int ptrace_getxregs(struct task_struct *child, void __user *uregs) #if XTENSA_HAVE_COPROCESSORS /* Flush all coprocessor registers to memory. */ coprocessor_flush_all(ti); - ret |= __copy_to_user(&xtregs->cp0, &ti->xtregs_cp, - sizeof(xtregs_coprocessor_t)); + + for (i = 0; i < ARRAY_SIZE(cp_offsets); ++i) + ret |= __copy_to_user((char __user *)xtregs + + cp_offsets[i].elf_xtregs_offset, + (const char *)ti + + cp_offsets[i].ti_offset, + cp_offsets[i].sz); #endif ret |= __copy_to_user(&xtregs->opt, &regs->xtregs_opt, sizeof(xtregs->opt)); @@ -157,6 +187,7 @@ static int ptrace_setxregs(struct task_struct *child, void __user *uregs) struct pt_regs *regs = task_pt_regs(child); elf_xtregs_t *xtregs = uregs; int ret = 0; + int i __maybe_unused; if (!access_ok(VERIFY_READ, uregs, sizeof(elf_xtregs_t))) return -EFAULT; @@ -166,8 +197,11 @@ static int ptrace_setxregs(struct task_struct *child, void __user *uregs) coprocessor_flush_all(ti); coprocessor_release_all(ti); - ret |= __copy_from_user(&ti->xtregs_cp, &xtregs->cp0, - sizeof(xtregs_coprocessor_t)); + for (i = 0; i < ARRAY_SIZE(cp_offsets); ++i) + ret |= __copy_from_user((char *)ti + cp_offsets[i].ti_offset, + (const char __user *)xtregs + + cp_offsets[i].elf_xtregs_offset, + cp_offsets[i].sz); #endif ret |= __copy_from_user(&regs->xtregs_opt, &xtregs->opt, sizeof(xtregs->opt));