FAILED: patch "[PATCH] LoongArch: vDSO: Emit GNU_EH_FRAME correctly" failed to apply to 6.12-stable tree

index e2eca1a25b4e..a1bd6a3ee03a 100644
@@ -41,4 +41,40 @@
 	.cfi_endproc;					\
 	SYM_END(name, SYM_T_NONE)
 
+/*
+ * This is for the signal handler trampoline, which is used as the return
+ * address of the signal handlers in userspace instead of called normally.
+ * The long standing libgcc bug https://gcc.gnu.org/PR124050 requires a
+ * nop between .cfi_startproc and the actual address of the trampoline, so
+ * we cannot simply use SYM_FUNC_START.
+ *
+ * This wrapper also contains all the .cfi_* directives for recovering
+ * the content of the GPRs and the "return address" (where the rt_sigreturn
+ * syscall will jump to), assuming there is a struct rt_sigframe (where
+ * a struct sigcontext containing those information we need to recover) at
+ * $sp.  The "DWARF for the LoongArch(TM) Architecture" manual states
+ * column 0 is for $zero, but it does not make too much sense to
+ * save/restore the hardware zero register.  Repurpose this column here
+ * for the return address (here it's not the content of $ra we cannot use
+ * the default column 3).
+ */
+#define SYM_SIGFUNC_START(name)				\
+	.cfi_startproc;					\
+	.cfi_signal_frame;				\
+	.cfi_def_cfa 3, RT_SIGFRAME_SC;			\
+	.cfi_return_column 0;				\
+	.cfi_offset 0, SC_PC;				\
+							\
+	.irp num, 1,  2,  3,  4,  5,  6,  7,  8, 	\
+		  9,  10, 11, 12, 13, 14, 15, 16,	\
+		  17, 18, 19, 20, 21, 22, 23, 24,	\
+		  25, 26, 27, 28, 29, 30, 31;		\
+	.cfi_offset \num, SC_REGS + \num * SZREG;	\
+	.endr;						\
+							\
+	nop;						\
+	SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)
+
+#define SYM_SIGFUNC_END(name) SYM_FUNC_END(name)
+
 #endif

new file mode 100644
index 000000000000..109298b8d7e0
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#include <asm/siginfo.h>
+#include <asm/ucontext.h>
+
+struct rt_sigframe {
+	struct siginfo rs_info;
+	struct ucontext rs_uctx;
+};

index 3017c7157600..2cc953f113ac 100644
@@ -16,6 +16,7 @@
 #include <asm/ptrace.h>
 #include <asm/processor.h>
 #include <asm/ftrace.h>
+#include <asm/sigframe.h>
 #include <vdso/datapage.h>
 
 static void __used output_ptreg_defines(void)

@@ -220,6 +221,7 @@ static void __used output_sc_defines(void)
 	COMMENT("Linux sigcontext offsets.");
 	OFFSET(SC_REGS, sigcontext, sc_regs);
 	OFFSET(SC_PC, sigcontext, sc_pc);
+	OFFSET(RT_SIGFRAME_SC, rt_sigframe, rs_uctx.uc_mcontext);
 	BLANK();
 }
 

index c9f7ca778364..d4151d2fb82e 100644
@@ -35,6 +35,7 @@
 #include <asm/cpu-features.h>
 #include <asm/fpu.h>
 #include <asm/lbt.h>
+#include <asm/sigframe.h>
 #include <asm/ucontext.h>
 #include <asm/vdso.h>
 

@@ -51,11 +52,6 @@
 #define lock_lbt_owner()	({ preempt_disable(); pagefault_disable(); })
 #define unlock_lbt_owner()	({ pagefault_enable(); preempt_enable(); })
 
-struct rt_sigframe {
-	struct siginfo rs_info;
-	struct ucontext rs_uctx;
-};
-
 struct _ctx_layout {
 	struct sctx_info *addr;
 	unsigned int size;

index 7e9edc1cb610d..39f706f14baca 100644
@@ -30,8 +30,7 @@ static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, uns
 
 static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void)
 {
-	return (const struct vdso_rng_data *)(get_vdso_data() + VVAR_LOONGARCH_PAGES_START *
-	       PAGE_SIZE + offsetof(struct loongarch_vdso_data, rng_data));
+	return &_loongarch_data.rng_data;
 }
 
 #endif /* !__ASSEMBLY__ */

index 2d1a9c27af292..edb428204375c 100644
@@ -91,14 +91,14 @@ static inline bool loongarch_vdso_hres_capable(void)
 
 static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
 {
-	return (const struct vdso_data *)get_vdso_data();
+	return _vdso_data;
 }
 
 #ifdef CONFIG_TIME_NS
 static __always_inline
 const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
 {
-	return (const struct vdso_data *)(get_vdso_data() + VVAR_TIMENS_PAGE_OFFSET * PAGE_SIZE);
+	return _timens_data;
 }
 #endif
 #endif /* !__ASSEMBLY__ */

index e31ac7474513c..1c183a9b2115a 100644
@@ -48,23 +48,7 @@ enum vvar_pages {
 
 #define VVAR_SIZE (VVAR_NR_PAGES << PAGE_SHIFT)
 
-static inline unsigned long get_vdso_base(void)
-{
-	unsigned long addr;
-
-	__asm__(
-	" la.pcrel %0, _start\n"
-	: "=r" (addr)
-	:
-	:);
-
-	return addr;
-}
-
-static inline unsigned long get_vdso_data(void)
-{
-	return get_vdso_base() - VVAR_SIZE;
-}
+extern struct loongarch_vdso_data _loongarch_data __attribute__((visibility("hidden")));
 
 #endif /* __ASSEMBLY__ */
 

index 73954aa226646..e476c143181a7 100644
@@ -16,6 +16,7 @@
 #include <asm/ptrace.h>
 #include <asm/processor.h>
 #include <asm/ftrace.h>
+#include <vdso/datapage.h>
 
 static void __used output_ptreg_defines(void)
 {

@@ -311,3 +312,11 @@ static void __used output_kvm_defines(void)
 	OFFSET(KVM_GPGD, kvm, arch.pgd);
 	BLANK();
 }
+
+static void __used output_vdso_defines(void)
+{
+	COMMENT("LoongArch vDSO offsets.");
+
+	DEFINE(__VVAR_PAGES, VVAR_NR_PAGES);
+	BLANK();
+}

index 9e445be39763a..0db51258b2a7c 100644
@@ -21,7 +21,7 @@ static __always_inline int read_cpu_id(void)
 
 static __always_inline const struct vdso_pcpu_data *get_pcpu_data(void)
 {
-	return (struct vdso_pcpu_data *)(get_vdso_data() + VVAR_LOONGARCH_PAGES_START * PAGE_SIZE);
+	return _loongarch_data.pdata;
 }
 
 extern

index e2eca1a25b4ef..a1bd6a3ee03a1 100644
@@ -41,4 +41,40 @@
 	.cfi_endproc;					\
 	SYM_END(name, SYM_T_NONE)
 
+/*
+ * This is for the signal handler trampoline, which is used as the return
+ * address of the signal handlers in userspace instead of called normally.
+ * The long standing libgcc bug https://gcc.gnu.org/PR124050 requires a
+ * nop between .cfi_startproc and the actual address of the trampoline, so
+ * we cannot simply use SYM_FUNC_START.
+ *
+ * This wrapper also contains all the .cfi_* directives for recovering
+ * the content of the GPRs and the "return address" (where the rt_sigreturn
+ * syscall will jump to), assuming there is a struct rt_sigframe (where
+ * a struct sigcontext containing those information we need to recover) at
+ * $sp.  The "DWARF for the LoongArch(TM) Architecture" manual states
+ * column 0 is for $zero, but it does not make too much sense to
+ * save/restore the hardware zero register.  Repurpose this column here
+ * for the return address (here it's not the content of $ra we cannot use
+ * the default column 3).
+ */
+#define SYM_SIGFUNC_START(name)				\
+	.cfi_startproc;					\
+	.cfi_signal_frame;				\
+	.cfi_def_cfa 3, RT_SIGFRAME_SC;			\
+	.cfi_return_column 0;				\
+	.cfi_offset 0, SC_PC;				\
+							\
+	.irp num, 1,  2,  3,  4,  5,  6,  7,  8, 	\
+		  9,  10, 11, 12, 13, 14, 15, 16,	\
+		  17, 18, 19, 20, 21, 22, 23, 24,	\
+		  25, 26, 27, 28, 29, 30, 31;		\
+	.cfi_offset \num, SC_REGS + \num * SZREG;	\
+	.endr;						\
+							\
+	nop;						\
+	SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)
+
+#define SYM_SIGFUNC_END(name) SYM_FUNC_END(name)
+
 #endif

new file mode 100644
index 0000000000000..109298b8d7e0b
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#include <asm/siginfo.h>
+#include <asm/ucontext.h>
+
+struct rt_sigframe {
+	struct siginfo rs_info;
+	struct ucontext rs_uctx;
+};

index e476c143181a7..1ad6d9e2c4328 100644
@@ -16,6 +16,7 @@
 #include <asm/ptrace.h>
 #include <asm/processor.h>
 #include <asm/ftrace.h>
+#include <asm/sigframe.h>
 #include <vdso/datapage.h>
 
 static void __used output_ptreg_defines(void)

@@ -220,6 +221,7 @@ static void __used output_sc_defines(void)
 	COMMENT("Linux sigcontext offsets.");
 	OFFSET(SC_REGS, sigcontext, sc_regs);
 	OFFSET(SC_PC, sigcontext, sc_pc);
+	OFFSET(RT_SIGFRAME_SC, rt_sigframe, rs_uctx.uc_mcontext);
 	BLANK();
 }
 

index c9f7ca778364e..d4151d2fb82ee 100644
@@ -35,6 +35,7 @@
 #include <asm/cpu-features.h>
 #include <asm/fpu.h>
 #include <asm/lbt.h>
+#include <asm/sigframe.h>
 #include <asm/ucontext.h>
 #include <asm/vdso.h>
 

@@ -51,11 +52,6 @@
 #define lock_lbt_owner()	({ preempt_disable(); pagefault_disable(); })
 #define unlock_lbt_owner()	({ pagefault_enable(); preempt_enable(); })
 
-struct rt_sigframe {
-	struct siginfo rs_info;
-	struct ucontext rs_uctx;
-};
-
 struct _ctx_layout {
 	struct sctx_info *addr;
 	unsigned int size;