From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 21A0B2C0094 for ; Fri, 21 Dec 2012 05:41:58 +1100 (EST) Subject: Re: [v1][PATCH 3/6] book3e/kgdb: update thread's dbcr0 Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: text/plain; charset=us-ascii From: Kumar Gala In-Reply-To: <1355994510-11934-4-git-send-email-tiejun.chen@windriver.com> Date: Thu, 20 Dec 2012 12:41:53 -0600 Message-Id: References: <1355994510-11934-1-git-send-email-tiejun.chen@windriver.com> <1355994510-11934-4-git-send-email-tiejun.chen@windriver.com> To: Tiejun Chen Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, jason.wessel@windriver.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Dec 20, 2012, at 3:08 AM, Tiejun Chen wrote: > 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. >=20 > So here we also update thread's dbcr0 to make sure the current > can go back with that missed dbcr0 configuration. >=20 > Signed-off-by: Tiejun Chen > --- > arch/powerpc/kernel/kgdb.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) >=20 > 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] =3D=3D 's') { > #ifdef CONFIG_PPC_ADV_DEBUG_REGS > +#ifdef CONFIG_PPC_BOOK3E Should this really be CONFIG_PPC64 or CONFIG_PPC_BOOK3E_64? > + /* 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 =3D > + 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 Can we code this so we don't need the #else? > linux_regs->msr |=3D MSR_DE; > #else > linux_regs->msr |=3D MSR_SE; > --=20 > 1.7.9.5 >=20 > -- > To unsubscribe from this list: send the line "unsubscribe = linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/