From: Sasha Levin <sashal@kernel•org>
To: linux-kernel@vger•kernel.org, stable@vger•kernel.org
Cc: Scott Wood <oss@buserror•net>,
linuxppc-dev@lists•ozlabs.org, Sasha Levin <sashal@kernel•org>
Subject: [PATCH AUTOSEL 4.14 076/127] powerpc/83xx: handle machine check caused by watchdog timer
Date: Fri, 22 Nov 2019 00:54:54 -0500 [thread overview]
Message-ID: <20191122055544.3299-75-sashal@kernel.org> (raw)
In-Reply-To: <20191122055544.3299-1-sashal@kernel.org>
From: Christophe Leroy <christophe.leroy@c-s•fr>
[ Upstream commit 0deae39cec6dab3a66794f3e9e83ca4dc30080f1 ]
When the watchdog timer is set in interrupt mode, it causes a
machine check when it times out. The purpose of this mode is to
ease debugging, not to crash the kernel and reboot the machine.
This patch implements a special handling for that, in order to not
crash the kernel if the watchdog times out while in interrupt or
within the idle task.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s•fr>
[scottwood: added missing #include]
Signed-off-by: Scott Wood <oss@buserror•net>
Signed-off-by: Sasha Levin <sashal@kernel•org>
---
arch/powerpc/include/asm/cputable.h | 1 +
arch/powerpc/include/asm/reg.h | 2 ++
arch/powerpc/kernel/cputable.c | 10 ++++++----
arch/powerpc/platforms/83xx/misc.c | 17 +++++++++++++++++
4 files changed, 26 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h
index 7e3ccf21830e6..e4451b30d7e32 100644
--- a/arch/powerpc/include/asm/cputable.h
+++ b/arch/powerpc/include/asm/cputable.h
@@ -45,6 +45,7 @@ extern int machine_check_e500(struct pt_regs *regs);
extern int machine_check_e200(struct pt_regs *regs);
extern int machine_check_47x(struct pt_regs *regs);
int machine_check_8xx(struct pt_regs *regs);
+int machine_check_83xx(struct pt_regs *regs);
extern void cpu_down_flush_e500v2(void);
extern void cpu_down_flush_e500mc(void);
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index b779f3ccd4126..05f3c2b3aa0ec 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -733,6 +733,8 @@
#define SRR1_PROGTRAP 0x00020000 /* Trap */
#define SRR1_PROGADDR 0x00010000 /* SRR0 contains subsequent addr */
+#define SRR1_MCE_MCP 0x00080000 /* Machine check signal caused interrupt */
+
#define SPRN_HSRR0 0x13A /* Save/Restore Register 0 */
#define SPRN_HSRR1 0x13B /* Save/Restore Register 1 */
#define HSRR1_DENORM 0x00100000 /* Denorm exception */
diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c
index 760872916013d..da4b0e3792380 100644
--- a/arch/powerpc/kernel/cputable.c
+++ b/arch/powerpc/kernel/cputable.c
@@ -1185,6 +1185,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.machine_check = machine_check_generic,
.platform = "ppc603",
},
+#ifdef CONFIG_PPC_83xx
{ /* e300c1 (a 603e core, plus some) on 83xx */
.pvr_mask = 0x7fff0000,
.pvr_value = 0x00830000,
@@ -1195,7 +1196,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.cpu_setup = __setup_cpu_603,
- .machine_check = machine_check_generic,
+ .machine_check = machine_check_83xx,
.platform = "ppc603",
},
{ /* e300c2 (an e300c1 core, plus some, minus FPU) on 83xx */
@@ -1209,7 +1210,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.cpu_setup = __setup_cpu_603,
- .machine_check = machine_check_generic,
+ .machine_check = machine_check_83xx,
.platform = "ppc603",
},
{ /* e300c3 (e300c1, plus one IU, half cache size) on 83xx */
@@ -1223,7 +1224,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.cpu_setup = __setup_cpu_603,
- .machine_check = machine_check_generic,
+ .machine_check = machine_check_83xx,
.num_pmcs = 4,
.oprofile_cpu_type = "ppc/e300",
.oprofile_type = PPC_OPROFILE_FSL_EMB,
@@ -1240,12 +1241,13 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.cpu_setup = __setup_cpu_603,
- .machine_check = machine_check_generic,
+ .machine_check = machine_check_83xx,
.num_pmcs = 4,
.oprofile_cpu_type = "ppc/e300",
.oprofile_type = PPC_OPROFILE_FSL_EMB,
.platform = "ppc603",
},
+#endif
{ /* default match, we assume split I/D cache & TB (non-601)... */
.pvr_mask = 0x00000000,
.pvr_value = 0x00000000,
diff --git a/arch/powerpc/platforms/83xx/misc.c b/arch/powerpc/platforms/83xx/misc.c
index d75c9816a5c92..2b6589fe812dd 100644
--- a/arch/powerpc/platforms/83xx/misc.c
+++ b/arch/powerpc/platforms/83xx/misc.c
@@ -14,6 +14,7 @@
#include <linux/of_platform.h>
#include <linux/pci.h>
+#include <asm/debug.h>
#include <asm/io.h>
#include <asm/hw_irq.h>
#include <asm/ipic.h>
@@ -150,3 +151,19 @@ void __init mpc83xx_setup_arch(void)
mpc83xx_setup_pci();
}
+
+int machine_check_83xx(struct pt_regs *regs)
+{
+ u32 mask = 1 << (31 - IPIC_MCP_WDT);
+
+ if (!(regs->msr & SRR1_MCE_MCP) || !(ipic_get_mcp_status() & mask))
+ return machine_check_generic(regs);
+ ipic_clear_mcp_status(mask);
+
+ if (debugger_fault_handler(regs))
+ return 1;
+
+ die("Watchdog NMI Reset", regs, 0);
+
+ return 1;
+}
--
2.20.1
next prev parent reply other threads:[~2019-11-22 7:02 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20191122055544.3299-1-sashal@kernel.org>
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 053/127] powerpc/book3s/32: fix number of bats in p/v_block_mapped() Sasha Levin
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 054/127] powerpc/xmon: fix dump_segments() Sasha Levin
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 064/127] powerpc/perf: Fix unit_sel/cache_sel checks Sasha Levin
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 065/127] powerpc/prom: fix early DEBUG messages Sasha Levin
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 066/127] powerpc/mm: Make NULL pointer deferences explicit on bad page faults Sasha Levin
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 067/127] powerpc/44x/bamboo: Fix PCI range Sasha Levin
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 069/127] powerpc/powernv/eeh/npu: Fix uninitialized variables in opal_pci_eeh_freeze_status Sasha Levin
2019-11-22 5:54 ` Sasha Levin [this message]
2019-11-22 5:54 ` [PATCH AUTOSEL 4.14 077/127] powerpc/pseries: Fix node leak in update_lmb_associativity_index() Sasha Levin
2019-11-22 5:55 ` [PATCH AUTOSEL 4.14 090/127] net/wan/fsl_ucc_hdlc: Avoid double free in ucc_hdlc_probe() Sasha Levin
2019-11-22 5:55 ` [PATCH AUTOSEL 4.14 126/127] powerpc/pseries/dlpar: Fix a missing check in dlpar_parse_cc_property() Sasha Levin
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