Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-16 17:12:06 +00:00
Code Issues Packages Projects Releases Wiki Activity

powerpc/kprobes: Fix jprobes on ABI v2 (LE)

Browse Source 
In commit 721aeaa9 "Build little endian ppc64 kernel with ABIv2", we
missed some updates required in the kprobes code to make jprobes work
when the kernel is built with ABI v2.

Firstly update arch_deref_entry_point() to do the right thing. Now that
we have added ppc_global_function_entry() we can just always use that, it
will do the right thing for 32 & 64 bit and ABI v1 & v2.

Secondly we need to update the code that sets up the register state before
calling the jprobe handler. On ABI v1 we setup r2 to hold the TOC, on ABI
v2 we need to populate r12 with the function entry point address.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Michael Ellerman 2014-06-23 13:23:31 +10:00 committed by Benjamin Herrenschmidt
parent 072c4c018e
commit 2f0143c91d
1 changed files with 6 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
arch/powerpc/kernel/kprobes.c
View File

@ -32,6 +32,7 @@
#include <linux/module.h>
#include <linux/kdebug.h>
#include <linux/slab.h>
#include <asm/code-patching.h>
#include <asm/cacheflush.h>
#include <asm/sstep.h>
#include <asm/uaccess.h>
@ -491,12 +492,10 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
return ret;
}
#ifdef CONFIG_PPC64
unsigned long arch_deref_entry_point(void *entry)
{
return ((func_descr_t *)entry)->entry;
return ppc_global_function_entry(entry);
}
#endif
int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
{
@ -508,7 +507,11 @@ int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
/* setup return addr to the jprobe handler routine */
regs->nip = arch_deref_entry_point(jp->entry);
#ifdef CONFIG_PPC64
#if defined(_CALL_ELF) && _CALL_ELF == 2
regs->gpr[12] = (unsigned long)jp->entry;
#else
regs->gpr[2] = (unsigned long)(((func_descr_t *)jp->entry)->toc);
#endif
#endif
return 1;