[PATCH 2/2] PPC_BOOK3E/KGDB: support kgdb kernel space
From: Tiejun Chen <hidden>
Date: 2012-10-17 10:50:35
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
We can support KGDB with current debug exception for BOOK3E, so we should initial specific dbg_kstack to avoid overwriting other thing. Signed-off-by: Tiejun Chen <redacted> --- arch/powerpc/kernel/exceptions-64e.S | 4 ++++ arch/powerpc/kernel/paca.c | 10 ++++++++++ 2 files changed, 14 insertions(+)
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 4684e33..ed5862d 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S@@ -539,11 +539,15 @@ kernel_dbg_exc: rfdi /* Normal debug exception */ +#ifndef CONFIG_KGDB /* XXX We only handle coming from userspace for now since we can't * quite save properly an interrupted kernel state yet */ 1: andi. r14,r11,MSR_PR; /* check for userspace again */ beq kernel_dbg_exc; /* if from kernel mode */ +#else +1: +#endif /* Now we mash up things to make it look like we are coming on a * normal exception
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
index cd6da85..28a5141 100644
--- a/arch/powerpc/kernel/paca.c
+++ b/arch/powerpc/kernel/paca.c@@ -122,6 +122,13 @@ EXPORT_SYMBOL(paca); struct paca_struct boot_paca; +void *debug_kstack; +static void allocate_dbg_kstack(unsigned long limit) +{ + debug_kstack = __va(memblock_alloc_base(THREAD_SIZE, + THREAD_SIZE, limit)); +} + void __init initialise_paca(struct paca_struct *new_paca, int cpu) { /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB
@@ -133,6 +140,7 @@ void __init initialise_paca(struct paca_struct *new_paca, int cpu) new_paca->lppaca_ptr = new_lppaca(cpu); #else new_paca->kernel_pgd = swapper_pg_dir; + new_paca->dbg_kstack = debug_kstack; #endif new_paca->lock_token = 0x8000; new_paca->paca_index = cpu;
@@ -192,6 +200,8 @@ void __init allocate_pacas(void) allocate_lppacas(nr_cpu_ids, limit); + allocate_dbg_kstack(limit); + /* Can't use for_each_*_cpu, as they aren't functional yet */ for (cpu = 0; cpu < nr_cpu_ids; cpu++) initialise_paca(&paca[cpu], cpu);
--
1.7.9.5