powerpc/32: Set user/kernel boundary at TASK_SIZE instead of PAGE_OFFSET
authorChristophe Leroy <christophe.leroy@csgroup.eu>
Mon, 29 Jun 2020 11:15:23 +0000 (11:15 +0000)
committerMichael Ellerman <mpe@ellerman.id.au>
Sun, 26 Jul 2020 14:01:30 +0000 (00:01 +1000)
User space stops at TASK_SIZE. At the moment, kernel space starts
at PAGE_OFFSET.

In order to use space between TASK_SIZE and PAGE_OFFSET for modules,
make TASK_SIZE the limit between user and kernel space.

Note that fault.c already considers TASK_SIZE as the boundary between
user and kernel space.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b38b52cd8dabbb56fbd6f9219d6f3cdccbb43b44.1593428200.git.christophe.leroy@csgroup.eu
arch/powerpc/include/asm/page.h
arch/powerpc/mm/ptdump/ptdump.c

index a63fe6f3a0ff81d0c29ae959a17c282a72213483..254687258f42b1673d4becc5ff213a32db18bb24 100644 (file)
@@ -255,8 +255,10 @@ static inline bool pfn_valid(unsigned long pfn)
  */
 #ifdef CONFIG_PPC_BOOK3E_64
 #define is_kernel_addr(x)      ((x) >= 0x8000000000000000ul)
-#else
+#elif defined(CONFIG_PPC_BOOK3S_64)
 #define is_kernel_addr(x)      ((x) >= PAGE_OFFSET)
+#else
+#define is_kernel_addr(x)      ((x) >= TASK_SIZE)
 #endif
 
 #ifndef CONFIG_PPC_BOOK3S_64
index de6e05ef871c1b732b3664ced8473ee01359c9b1..9d942136c7beed962107bdeb3e256da8f6a86700 100644 (file)
@@ -348,7 +348,11 @@ static void populate_markers(void)
 {
        int i = 0;
 
+#ifdef CONFIG_PPC64
        address_markers[i++].start_address = PAGE_OFFSET;
+#else
+       address_markers[i++].start_address = TASK_SIZE;
+#endif
        address_markers[i++].start_address = VMALLOC_START;
        address_markers[i++].start_address = VMALLOC_END;
 #ifdef CONFIG_PPC64
@@ -385,7 +389,7 @@ static int ptdump_show(struct seq_file *m, void *v)
        struct pg_state st = {
                .seq = m,
                .marker = address_markers,
-               .start_address = PAGE_OFFSET,
+               .start_address = IS_ENABLED(CONFIG_PPC64) ? PAGE_OFFSET : TASK_SIZE,
        };
 
 #ifdef CONFIG_PPC64
@@ -429,7 +433,7 @@ void ptdump_check_wx(void)
                .seq = NULL,
                .marker = address_markers,
                .check_wx = true,
-               .start_address = PAGE_OFFSET,
+               .start_address = IS_ENABLED(CONFIG_PPC64) ? PAGE_OFFSET : TASK_SIZE,
        };
 
 #ifdef CONFIG_PPC64