[v1][PATCH 3/6] book3e/kgdb: update thread's dbcr0
From: Tiejun Chen <hidden>
Date: 2012-12-20 09:09:08
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
gdb always need to generate a single step properly to invoke a kgdb state. But with lazy interrupt, book3e can't always trigger a debug exception with a single step since the current is blocked for handling those pending exception, then we miss that expected dbcr configuration at last to generate a debug exception. So here we also update thread's dbcr0 to make sure the current can go back with that missed dbcr0 configuration. Signed-off-by: Tiejun Chen <redacted> --- arch/powerpc/kernel/kgdb.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index c470a40..516b44b 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c@@ -426,8 +426,18 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code, /* set the trace bit if we're stepping */ if (remcom_in_buffer[0] == 's') { #ifdef CONFIG_PPC_ADV_DEBUG_REGS +#ifdef CONFIG_PPC_BOOK3E + /* With lazy interrut we have to update thread dbcr0 here + * to make sure we can set debug properly at last to invoke + * kgdb again to work well. + */ + current->thread.dbcr0 = + mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM; + mtspr(SPRN_DBCR0, current->thread.dbcr0); +#else mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM); +#endif linux_regs->msr |= MSR_DE; #else linux_regs->msr |= MSR_SE;
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1.7.9.5