module: fix module loading failure of large kernel modules for parisc

When creating the final layout of a kernel module in memory, allow the module loader to reserve some additional memory in front of a given section. This is currently only needed for the parisc port which needs to put the stub entries there to fulfill the 17/22bit PCREL relocations with large kernel modules like xfs. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (renamed fn)

module: fix module loading failure of large kernel modules for parisc
When creating the final layout of a kernel module in memory, allow the module loader to reserve some additional memory in front of a given section. This is currently only needed for the parisc port which needs to put the stub entries there to fulfill the 17/22bit PCREL relocations with large kernel modules like xfs. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (renamed fn)
Helge Deller · Rusty Russell
1 parent d1e99d7ae4
Showing 2 changed files with 16 additions and 3 deletions Side-by-side Diff
include/linux/moduleloader.h
kernel/module.c
@@ -13,6 +13,9 @@
 			      char *secstrings,
 			      struct module *mod);
  
+/* Additional bytes needed by arch in front of individual sections */
+unsigned int arch_mod_section_prepend(struct module *mod, unsigned int section);
+
 /* Allocator used for allocating struct module, core sections and init
    sections.  Returns NULL on failure. */
 void *module_alloc(unsigned long size);
@@ -1578,11 +1578,21 @@
 	return ret;
 }
  
+/* Additional bytes needed by arch in front of individual sections */
+unsigned int __weak arch_mod_section_prepend(struct module *mod,
+					     unsigned int section)
+{
+	/* default implementation just returns zero */
+	return 0;
+}
+
 /* Update size with this section: return offset. */
-static long get_offset(unsigned int *size, Elf_Shdr *sechdr)
+static long get_offset(struct module *mod, unsigned int *size,
+		       Elf_Shdr *sechdr, unsigned int section)
 {
 	long ret;
  
+	*size += arch_mod_section_prepend(mod, section);
 	ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
 	*size = ret + sechdr->sh_size;
 	return ret;
@@ -1622,7 +1632,7 @@
 			    || strncmp(secstrings + s->sh_name,
 				       ".init", 5) == 0)
 				continue;
-			s->sh_entsize = get_offset(&mod->core_size, s);
+			s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
 			DEBUGP("\t%s\n", secstrings + s->sh_name);
 		}
 		if (m == 0)
@@ -1640,7 +1650,7 @@
 			    || strncmp(secstrings + s->sh_name,
 				       ".init", 5) != 0)
 				continue;
-			s->sh_entsize = (get_offset(&mod->init_size, s)
+			s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
 					 | INIT_OFFSET_MASK);
 			DEBUGP("\t%s\n", secstrings + s->sh_name);
 		}
...	...	@@ -13,6 +13,9 @@
13	13	char *secstrings,
14	14	struct module *mod);
15	15
	16	+/* Additional bytes needed by arch in front of individual sections */
	17	+unsigned int arch_mod_section_prepend(struct module *mod, unsigned int section);
	18	+
16	19	/* Allocator used for allocating struct module, core sections and init
17	20	sections. Returns NULL on failure. */
18	21	void *module_alloc(unsigned long size);
...	...	@@ -1578,11 +1578,21 @@
1578	1578	return ret;
1579	1579	}
1580	1580
	1581	+/* Additional bytes needed by arch in front of individual sections */
	1582	+unsigned int __weak arch_mod_section_prepend(struct module *mod,
	1583	+ unsigned int section)
	1584	+{
	1585	+ /* default implementation just returns zero */
	1586	+ return 0;
	1587	+}
	1588	+
1581	1589	/* Update size with this section: return offset. */
1582		-static long get_offset(unsigned int size, Elf_Shdr sechdr)
	1590	+static long get_offset(struct module mod, unsigned int size,
	1591	+ Elf_Shdr *sechdr, unsigned int section)
1583	1592	{
1584	1593	long ret;
1585	1594
	1595	+ *size += arch_mod_section_prepend(mod, section);
1586	1596	ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1587	1597	*size = ret + sechdr->sh_size;
1588	1598	return ret;
...	...	@@ -1622,7 +1632,7 @@
1622	1632	\|\| strncmp(secstrings + s->sh_name,
1623	1633	".init", 5) == 0)
1624	1634	continue;
1625		- s->sh_entsize = get_offset(&mod->core_size, s);
	1635	+ s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1626	1636	DEBUGP("\t%s\n", secstrings + s->sh_name);
1627	1637	}
1628	1638	if (m == 0)
...	...	@@ -1640,7 +1650,7 @@
1640	1650	\|\| strncmp(secstrings + s->sh_name,
1641	1651	".init", 5) != 0)
1642	1652	continue;
1643		- s->sh_entsize = (get_offset(&mod->init_size, s)
	1653	+ s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1644	1654	\| INIT_OFFSET_MASK);
1645	1655	DEBUGP("\t%s\n", secstrings + s->sh_name);
1646	1656	}