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@@ -1,103 +0,0 @@
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-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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-From: Thomas Lamprecht <[email protected]>
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-Date: Wed, 3 Apr 2019 18:41:50 +0200
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-Subject: [PATCH] x86/fpu: backport copy_kernel_to_XYZ_err helpers
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-MIME-Version: 1.0
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-Content-Type: text/plain; charset=UTF-8
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-Content-Transfer-Encoding: 8bit
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-
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-partial cherry-pick from upstream 5.2 "86/fpu: Restore from kernel
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-memory on the 64-bit path too"
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-commit 926b21f37b072ae4c117052de45a975c6d468fec
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-Author: Sebastian Andrzej Siewior <[email protected]>
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-
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-Namely, only backport the added helpers, none of the semantic changes.
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-
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-relevant parts of the original commit message:
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-> In order to avoid that mess, copy the FPU state from userland, validate
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-> it and then load it. The copy_kernel_…() helpers are basically just
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-> like the old helpers except that they operate on kernel memory and the
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-> fault handler just sets the error value and the caller handles it.
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-
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-Link: https://lkml.kernel.org/r/[email protected]
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-(partial cherry picked from commit 926b21f37b072ae4c117052de45a975c6d468fec)
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-Signed-off-by: Thomas Lamprecht <[email protected]>
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----
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- arch/x86/include/asm/fpu/internal.h | 43 +++++++++++++++++++++++++++++
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- 1 file changed, 43 insertions(+)
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-
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-diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
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-index fa2c93cb42a2..f3193ab0a2fb 100644
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---- a/arch/x86/include/asm/fpu/internal.h
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-+++ b/arch/x86/include/asm/fpu/internal.h
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-@@ -122,6 +122,21 @@ extern void fpstate_sanitize_xstate(struct fpu *fpu);
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- err; \
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- })
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-
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-+#define kernel_insn_err(insn, output, input...) \
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-+({ \
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-+ int err; \
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-+ asm volatile("1:" #insn "\n\t" \
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-+ "2:\n" \
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-+ ".section .fixup,\"ax\"\n" \
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-+ "3: movl $-1,%[err]\n" \
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-+ " jmp 2b\n" \
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-+ ".previous\n" \
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-+ _ASM_EXTABLE(1b, 3b) \
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-+ : [err] "=r" (err), output \
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-+ : "0"(0), input); \
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-+ err; \
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-+})
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-+
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- #define kernel_insn(insn, output, input...) \
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- asm volatile("1:" #insn "\n\t" \
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- "2:\n" \
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-@@ -158,6 +173,14 @@ static inline void copy_kernel_to_fxregs(struct fxregs_state *fx)
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- }
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- }
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-
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-+static inline int copy_kernel_to_fxregs_err(struct fxregs_state *fx)
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-+{
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-+ if (IS_ENABLED(CONFIG_X86_32))
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-+ return kernel_insn_err(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx));
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-+ else
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-+ return kernel_insn_err(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx));
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-+}
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-+
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- static inline int copy_user_to_fxregs(struct fxregs_state __user *fx)
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- {
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- if (IS_ENABLED(CONFIG_X86_32))
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-@@ -175,6 +198,11 @@ static inline void copy_kernel_to_fregs(struct fregs_state *fx)
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- kernel_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
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- }
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-
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-+static inline int copy_kernel_to_fregs_err(struct fregs_state *fx)
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-+{
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-+ return kernel_insn_err(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
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-+}
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-+
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- static inline int copy_user_to_fregs(struct fregs_state __user *fx)
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- {
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- return user_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx));
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-@@ -400,6 +428,21 @@ static inline int copy_user_to_xregs(struct xregs_state __user *buf, u64 mask)
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- return err;
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- }
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-
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-+/*
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-+ * Restore xstate from kernel space xsave area, return an error code instead of
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-+ * an exception.
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-+ */
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-+static inline int copy_kernel_to_xregs_err(struct xregs_state *xstate, u64 mask)
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-+{
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-+ u32 lmask = mask;
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-+ u32 hmask = mask >> 32;
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-+ int err;
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-+
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-+ XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
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-+
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-+ return err;
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-+}
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-+
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- /*
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- * These must be called with preempt disabled. Returns
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- * 'true' if the FPU state is still intact and we can
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Thomas Lamprecht