parisc architecture build-, trace-, backtrace- and page table fixes

Fix a build error in stracktrace.c, fix resolving of addresses to
 function names in backtraces, fix single-stepping in assembly code
 and flush userspace pte's when using set_pte_at().
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Merge tag 'for-5.16/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

Pull more parisc fixes from Helge Deller:
 "Fix a build error in stracktrace.c, fix resolving of addresses to
  function names in backtraces, fix single-stepping in assembly code and
  flush userspace pte's when using set_pte_at()"

* tag 'for-5.16/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc/entry: fix trace test in syscall exit path
  parisc: Flush kernel data mapping in set_pte_at() when installing pte for user page
  parisc: Fix implicit declaration of function '__kernel_text_address'
  parisc: Fix backtrace to always include init funtion names

arch/parisc/include/asm/pgtable.h

@@ -76,6 +76,8 @@ static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
 	purge_tlb_end(flags);
 }
 
+extern void __update_cache(pte_t pte);
+
 /* Certain architectures need to do special things when PTEs
  * within a page table are directly modified.  Thus, the following
  * hook is made available.
@@ -83,11 +85,14 @@ static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
 #define set_pte(pteptr, pteval)			\
 	do {					\
 		*(pteptr) = (pteval);		\
-		barrier();			\
+		mb();				\
 	} while(0)
 
 #define set_pte_at(mm, addr, pteptr, pteval)	\
 	do {					\
+		if (pte_present(pteval) &&	\
+		    pte_user(pteval))		\
+			__update_cache(pteval);	\
 		*(pteptr) = (pteval);		\
 		purge_tlb_entries(mm, addr);	\
 	} while (0)
@@ -303,6 +308,7 @@ extern unsigned long *empty_zero_page;
 
 #define pte_none(x)     (pte_val(x) == 0)
 #define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
+#define pte_user(x)	(pte_val(x) & _PAGE_USER)
 #define pte_clear(mm, addr, xp)  set_pte_at(mm, addr, xp, __pte(0))
 
 #define pmd_flag(x)	(pmd_val(x) & PxD_FLAG_MASK)
@@ -410,7 +416,7 @@ extern void paging_init (void);
 
 #define PG_dcache_dirty         PG_arch_1
 
-extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
+#define update_mmu_cache(vms,addr,ptep) __update_cache(*ptep)
 
 /* Encode and de-code a swap entry */
 

arch/parisc/kernel/cache.c

@@ -83,9 +83,9 @@ EXPORT_SYMBOL(flush_cache_all_local);
 #define pfn_va(pfn)	__va(PFN_PHYS(pfn))
 
 void
-update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
+__update_cache(pte_t pte)
 {
-	unsigned long pfn = pte_pfn(*ptep);
+	unsigned long pfn = pte_pfn(pte);
 	struct page *page;
 
 	/* We don't have pte special.  As a result, we can be called with

arch/parisc/kernel/entry.S

@@ -1805,7 +1805,7 @@ syscall_restore:
 
 	/* Are we being ptraced? */
 	LDREG	TASK_TI_FLAGS(%r1),%r19
-	ldi	_TIF_SYSCALL_TRACE_MASK,%r2
+	ldi	_TIF_SINGLESTEP|_TIF_BLOCKSTEP,%r2
 	and,COND(=)	%r19,%r2,%r0
 	b,n	syscall_restore_rfi
 

arch/parisc/kernel/stacktrace.c

@@ -8,6 +8,7 @@
  *
  *  TODO: Userspace stacktrace (CONFIG_USER_STACKTRACE_SUPPORT)
  */
+#include <linux/kernel.h>
 #include <linux/stacktrace.h>
 
 #include <asm/unwind.h>

arch/parisc/kernel/vmlinux.lds.S

@@ -57,6 +57,8 @@ SECTIONS
 {
 	. = KERNEL_BINARY_TEXT_START;
 
+	_stext = .;	/* start of kernel text, includes init code & data */
+
 	__init_begin = .;
 	HEAD_TEXT_SECTION
 	MLONGCALL_DISCARD(INIT_TEXT_SECTION(8))
@@ -80,7 +82,6 @@ SECTIONS
 	/* freed after init ends here */
 
 	_text = .;		/* Text and read-only data */
-	_stext = .;
 	MLONGCALL_KEEP(INIT_TEXT_SECTION(8))
 	.text ALIGN(PAGE_SIZE) : {
 		TEXT_TEXT