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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /arch/x86/lib/getuser.S
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'arch/x86/lib/getuser.S')
-rw-r--r--arch/x86/lib/getuser.S172
1 files changed, 172 insertions, 0 deletions
diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S
new file mode 100644
index 000000000..9d5654b8a
--- /dev/null
+++ b/arch/x86/lib/getuser.S
@@ -0,0 +1,172 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * __get_user functions.
+ *
+ * (C) Copyright 1998 Linus Torvalds
+ * (C) Copyright 2005 Andi Kleen
+ * (C) Copyright 2008 Glauber Costa
+ *
+ * These functions have a non-standard call interface
+ * to make them more efficient, especially as they
+ * return an error value in addition to the "real"
+ * return value.
+ */
+
+/*
+ * __get_user_X
+ *
+ * Inputs: %[r|e]ax contains the address.
+ *
+ * Outputs: %[r|e]ax is error code (0 or -EFAULT)
+ * %[r|e]dx contains zero-extended value
+ * %ecx contains the high half for 32-bit __get_user_8
+ *
+ *
+ * These functions should not modify any other registers,
+ * as they get called from within inline assembly.
+ */
+
+#include <linux/export.h>
+#include <linux/linkage.h>
+#include <linux/objtool.h>
+#include <asm/page_types.h>
+#include <asm/errno.h>
+#include <asm/asm-offsets.h>
+#include <asm/thread_info.h>
+#include <asm/asm.h>
+#include <asm/smap.h>
+#include <asm/runtime-const.h>
+
+#define ASM_BARRIER_NOSPEC ALTERNATIVE "", "lfence", X86_FEATURE_LFENCE_RDTSC
+
+.macro check_range size:req
+.if IS_ENABLED(CONFIG_X86_64)
+ RUNTIME_CONST_PTR USER_PTR_MAX, rdx
+ cmp %rdx, %rax
+ cmova %rdx, %rax
+.else
+ cmp $TASK_SIZE_MAX-\size+1, %eax
+ jae .Lbad_get_user
+ sbb %edx, %edx /* array_index_mask_nospec() */
+ and %edx, %eax
+.endif
+.endm
+
+.macro UACCESS op src dst
+1: \op \src,\dst
+ _ASM_EXTABLE_UA(1b, __get_user_handle_exception)
+.endm
+
+
+ .text
+SYM_FUNC_START(__get_user_1)
+ ANNOTATE_NOENDBR
+ check_range size=1
+ ASM_STAC
+ UACCESS movzbl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_1)
+EXPORT_SYMBOL(__get_user_1)
+
+SYM_FUNC_START(__get_user_2)
+ ANNOTATE_NOENDBR
+ check_range size=2
+ ASM_STAC
+ UACCESS movzwl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_2)
+EXPORT_SYMBOL(__get_user_2)
+
+SYM_FUNC_START(__get_user_4)
+ ANNOTATE_NOENDBR
+ check_range size=4
+ ASM_STAC
+ UACCESS movl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_4)
+EXPORT_SYMBOL(__get_user_4)
+
+SYM_FUNC_START(__get_user_8)
+ ANNOTATE_NOENDBR
+#ifndef CONFIG_X86_64
+ xor %ecx,%ecx
+#endif
+ check_range size=8
+ ASM_STAC
+#ifdef CONFIG_X86_64
+ UACCESS movq (%_ASM_AX),%rdx
+#else
+ UACCESS movl (%_ASM_AX),%edx
+ UACCESS movl 4(%_ASM_AX),%ecx
+#endif
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_8)
+EXPORT_SYMBOL(__get_user_8)
+
+/* .. and the same for __get_user, just without the range checks */
+SYM_FUNC_START(__get_user_nocheck_1)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+ UACCESS movzbl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_1)
+EXPORT_SYMBOL(__get_user_nocheck_1)
+
+SYM_FUNC_START(__get_user_nocheck_2)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+ UACCESS movzwl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_2)
+EXPORT_SYMBOL(__get_user_nocheck_2)
+
+SYM_FUNC_START(__get_user_nocheck_4)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+ UACCESS movl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_4)
+EXPORT_SYMBOL(__get_user_nocheck_4)
+
+SYM_FUNC_START(__get_user_nocheck_8)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+#ifdef CONFIG_X86_64
+ UACCESS movq (%_ASM_AX),%rdx
+#else
+ xor %ecx,%ecx
+ UACCESS movl (%_ASM_AX),%edx
+ UACCESS movl 4(%_ASM_AX),%ecx
+#endif
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_8)
+EXPORT_SYMBOL(__get_user_nocheck_8)
+
+
+SYM_CODE_START_LOCAL(__get_user_handle_exception)
+ ASM_CLAC
+.Lbad_get_user:
+ xor %edx,%edx
+ mov $(-EFAULT),%_ASM_AX
+ RET
+SYM_CODE_END(__get_user_handle_exception)