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-rw-r--r--arch/arm/kernel/armksyms.c4
-rw-r--r--arch/arm/kernel/module-plts.c87
-rw-r--r--arch/arm/kernel/module.lds1
-rw-r--r--arch/arm/kernel/setup.c10
-rw-r--r--arch/arm/kernel/smccc-call.S14
-rw-r--r--arch/arm/kernel/traps.c28
6 files changed, 97 insertions, 47 deletions
diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c
index 7e45f69a0ddc..8e8d20cdbce7 100644
--- a/arch/arm/kernel/armksyms.c
+++ b/arch/arm/kernel/armksyms.c
@@ -178,6 +178,6 @@ EXPORT_SYMBOL(__pv_offset);
#endif
#ifdef CONFIG_HAVE_ARM_SMCCC
-EXPORT_SYMBOL(arm_smccc_smc);
-EXPORT_SYMBOL(arm_smccc_hvc);
+EXPORT_SYMBOL(__arm_smccc_smc);
+EXPORT_SYMBOL(__arm_smccc_hvc);
#endif
diff --git a/arch/arm/kernel/module-plts.c b/arch/arm/kernel/module-plts.c
index 3a5cba90c971..3d0c2e4dda1d 100644
--- a/arch/arm/kernel/module-plts.c
+++ b/arch/arm/kernel/module-plts.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ * Copyright (C) 2014-2017 Linaro Ltd. <ard.biesheuvel@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@@ -31,9 +31,17 @@ struct plt_entries {
u32 lit[PLT_ENT_COUNT];
};
+static bool in_init(const struct module *mod, unsigned long loc)
+{
+ return loc - (u32)mod->init_layout.base < mod->init_layout.size;
+}
+
u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val)
{
- struct plt_entries *plt = (struct plt_entries *)mod->arch.plt->sh_addr;
+ struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
+ &mod->arch.init;
+
+ struct plt_entries *plt = (struct plt_entries *)pltsec->plt->sh_addr;
int idx = 0;
/*
@@ -41,9 +49,9 @@ u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val)
* relocations are sorted, this will be the last entry we allocated.
* (if one exists).
*/
- if (mod->arch.plt_count > 0) {
- plt += (mod->arch.plt_count - 1) / PLT_ENT_COUNT;
- idx = (mod->arch.plt_count - 1) % PLT_ENT_COUNT;
+ if (pltsec->plt_count > 0) {
+ plt += (pltsec->plt_count - 1) / PLT_ENT_COUNT;
+ idx = (pltsec->plt_count - 1) % PLT_ENT_COUNT;
if (plt->lit[idx] == val)
return (u32)&plt->ldr[idx];
@@ -53,8 +61,8 @@ u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val)
plt++;
}
- mod->arch.plt_count++;
- BUG_ON(mod->arch.plt_count * PLT_ENT_SIZE > mod->arch.plt->sh_size);
+ pltsec->plt_count++;
+ BUG_ON(pltsec->plt_count * PLT_ENT_SIZE > pltsec->plt->sh_size);
if (!idx)
/* Populate a new set of entries */
@@ -129,7 +137,7 @@ static bool duplicate_rel(Elf32_Addr base, const Elf32_Rel *rel, int num)
/* Count how many PLT entries we may need */
static unsigned int count_plts(const Elf32_Sym *syms, Elf32_Addr base,
- const Elf32_Rel *rel, int num)
+ const Elf32_Rel *rel, int num, Elf32_Word dstidx)
{
unsigned int ret = 0;
const Elf32_Sym *s;
@@ -144,13 +152,17 @@ static unsigned int count_plts(const Elf32_Sym *syms, Elf32_Addr base,
case R_ARM_THM_JUMP24:
/*
* We only have to consider branch targets that resolve
- * to undefined symbols. This is not simply a heuristic,
- * it is a fundamental limitation, since the PLT itself
- * is part of the module, and needs to be within range
- * as well, so modules can never grow beyond that limit.
+ * to symbols that are defined in a different section.
+ * This is not simply a heuristic, it is a fundamental
+ * limitation, since there is no guaranteed way to emit
+ * PLT entries sufficiently close to the branch if the
+ * section size exceeds the range of a branch
+ * instruction. So ignore relocations against defined
+ * symbols if they live in the same section as the
+ * relocation target.
*/
s = syms + ELF32_R_SYM(rel[i].r_info);
- if (s->st_shndx != SHN_UNDEF)
+ if (s->st_shndx == dstidx)
break;
/*
@@ -161,7 +173,12 @@ static unsigned int count_plts(const Elf32_Sym *syms, Elf32_Addr base,
* So we need to support them, but there is no need to
* take them into consideration when trying to optimize
* this code. So let's only check for duplicates when
- * the addend is zero.
+ * the addend is zero. (Note that calls into the core
+ * module via init PLT entries could involve section
+ * relative symbol references with non-zero addends, for
+ * which we may end up emitting duplicates, but the init
+ * PLT is released along with the rest of the .init
+ * region as soon as module loading completes.)
*/
if (!is_zero_addend_relocation(base, rel + i) ||
!duplicate_rel(base, rel, i))
@@ -174,7 +191,8 @@ static unsigned int count_plts(const Elf32_Sym *syms, Elf32_Addr base,
int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
char *secstrings, struct module *mod)
{
- unsigned long plts = 0;
+ unsigned long core_plts = 0;
+ unsigned long init_plts = 0;
Elf32_Shdr *s, *sechdrs_end = sechdrs + ehdr->e_shnum;
Elf32_Sym *syms = NULL;
@@ -184,13 +202,15 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
*/
for (s = sechdrs; s < sechdrs_end; ++s) {
if (strcmp(".plt", secstrings + s->sh_name) == 0)
- mod->arch.plt = s;
+ mod->arch.core.plt = s;
+ else if (strcmp(".init.plt", secstrings + s->sh_name) == 0)
+ mod->arch.init.plt = s;
else if (s->sh_type == SHT_SYMTAB)
syms = (Elf32_Sym *)s->sh_addr;
}
- if (!mod->arch.plt) {
- pr_err("%s: module PLT section missing\n", mod->name);
+ if (!mod->arch.core.plt || !mod->arch.init.plt) {
+ pr_err("%s: module PLT section(s) missing\n", mod->name);
return -ENOEXEC;
}
if (!syms) {
@@ -213,16 +233,29 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
/* sort by type and symbol index */
sort(rels, numrels, sizeof(Elf32_Rel), cmp_rel, NULL);
- plts += count_plts(syms, dstsec->sh_addr, rels, numrels);
+ if (strncmp(secstrings + dstsec->sh_name, ".init", 5) != 0)
+ core_plts += count_plts(syms, dstsec->sh_addr, rels,
+ numrels, s->sh_info);
+ else
+ init_plts += count_plts(syms, dstsec->sh_addr, rels,
+ numrels, s->sh_info);
}
- mod->arch.plt->sh_type = SHT_NOBITS;
- mod->arch.plt->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
- mod->arch.plt->sh_addralign = L1_CACHE_BYTES;
- mod->arch.plt->sh_size = round_up(plts * PLT_ENT_SIZE,
- sizeof(struct plt_entries));
- mod->arch.plt_count = 0;
-
- pr_debug("%s: plt=%x\n", __func__, mod->arch.plt->sh_size);
+ mod->arch.core.plt->sh_type = SHT_NOBITS;
+ mod->arch.core.plt->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
+ mod->arch.core.plt->sh_addralign = L1_CACHE_BYTES;
+ mod->arch.core.plt->sh_size = round_up(core_plts * PLT_ENT_SIZE,
+ sizeof(struct plt_entries));
+ mod->arch.core.plt_count = 0;
+
+ mod->arch.init.plt->sh_type = SHT_NOBITS;
+ mod->arch.init.plt->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
+ mod->arch.init.plt->sh_addralign = L1_CACHE_BYTES;
+ mod->arch.init.plt->sh_size = round_up(init_plts * PLT_ENT_SIZE,
+ sizeof(struct plt_entries));
+ mod->arch.init.plt_count = 0;
+
+ pr_debug("%s: plt=%x, init.plt=%x\n", __func__,
+ mod->arch.core.plt->sh_size, mod->arch.init.plt->sh_size);
return 0;
}
diff --git a/arch/arm/kernel/module.lds b/arch/arm/kernel/module.lds
index 05881e2b414c..eacb5c67f61e 100644
--- a/arch/arm/kernel/module.lds
+++ b/arch/arm/kernel/module.lds
@@ -1,3 +1,4 @@
SECTIONS {
.plt : { BYTE(0) }
+ .init.plt : { BYTE(0) }
}
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 34e3f3c45634..f4e54503afa9 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -81,7 +81,7 @@ __setup("fpe=", fpe_setup);
extern void init_default_cache_policy(unsigned long);
extern void paging_init(const struct machine_desc *desc);
extern void early_paging_init(const struct machine_desc *);
-extern void sanity_check_meminfo(void);
+extern void adjust_lowmem_bounds(void);
extern enum reboot_mode reboot_mode;
extern void setup_dma_zone(const struct machine_desc *desc);
@@ -1093,8 +1093,14 @@ void __init setup_arch(char **cmdline_p)
setup_dma_zone(mdesc);
xen_early_init();
efi_init();
- sanity_check_meminfo();
+ /*
+ * Make sure the calculation for lowmem/highmem is set appropriately
+ * before reserving/allocating any mmeory
+ */
+ adjust_lowmem_bounds();
arm_memblock_init(mdesc);
+ /* Memory may have been removed so recalculate the bounds. */
+ adjust_lowmem_bounds();
early_ioremap_reset();
diff --git a/arch/arm/kernel/smccc-call.S b/arch/arm/kernel/smccc-call.S
index 2e48b674aab1..e5d43066b889 100644
--- a/arch/arm/kernel/smccc-call.S
+++ b/arch/arm/kernel/smccc-call.S
@@ -46,17 +46,19 @@ UNWIND( .fnend)
/*
* void smccc_smc(unsigned long a0, unsigned long a1, unsigned long a2,
* unsigned long a3, unsigned long a4, unsigned long a5,
- * unsigned long a6, unsigned long a7, struct arm_smccc_res *res)
+ * unsigned long a6, unsigned long a7, struct arm_smccc_res *res,
+ * struct arm_smccc_quirk *quirk)
*/
-ENTRY(arm_smccc_smc)
+ENTRY(__arm_smccc_smc)
SMCCC SMCCC_SMC
-ENDPROC(arm_smccc_smc)
+ENDPROC(__arm_smccc_smc)
/*
* void smccc_hvc(unsigned long a0, unsigned long a1, unsigned long a2,
* unsigned long a3, unsigned long a4, unsigned long a5,
- * unsigned long a6, unsigned long a7, struct arm_smccc_res *res)
+ * unsigned long a6, unsigned long a7, struct arm_smccc_res *res,
+ * struct arm_smccc_quirk *quirk)
*/
-ENTRY(arm_smccc_hvc)
+ENTRY(__arm_smccc_hvc)
SMCCC SMCCC_HVC
-ENDPROC(arm_smccc_hvc)
+ENDPROC(__arm_smccc_hvc)
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 9688ec0c6ef4..1b304897aa12 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -152,30 +152,26 @@ static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
set_fs(fs);
}
-static void dump_instr(const char *lvl, struct pt_regs *regs)
+static void __dump_instr(const char *lvl, struct pt_regs *regs)
{
unsigned long addr = instruction_pointer(regs);
const int thumb = thumb_mode(regs);
const int width = thumb ? 4 : 8;
- mm_segment_t fs;
char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
int i;
/*
- * We need to switch to kernel mode so that we can use __get_user
- * to safely read from kernel space. Note that we now dump the
- * code first, just in case the backtrace kills us.
+ * Note that we now dump the code first, just in case the backtrace
+ * kills us.
*/
- fs = get_fs();
- set_fs(KERNEL_DS);
for (i = -4; i < 1 + !!thumb; i++) {
unsigned int val, bad;
if (thumb)
- bad = __get_user(val, &((u16 *)addr)[i]);
+ bad = get_user(val, &((u16 *)addr)[i]);
else
- bad = __get_user(val, &((u32 *)addr)[i]);
+ bad = get_user(val, &((u32 *)addr)[i]);
if (!bad)
p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ",
@@ -186,8 +182,20 @@ static void dump_instr(const char *lvl, struct pt_regs *regs)
}
}
printk("%sCode: %s\n", lvl, str);
+}
- set_fs(fs);
+static void dump_instr(const char *lvl, struct pt_regs *regs)
+{
+ mm_segment_t fs;
+
+ if (!user_mode(regs)) {
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+ __dump_instr(lvl, regs);
+ set_fs(fs);
+ } else {
+ __dump_instr(lvl, regs);
+ }
}
#ifdef CONFIG_ARM_UNWIND
generated by cgit v1.2.3 (git 2.0.4) at 2024-08-18 07:32:21 +0000