| Message ID | 20230815023426.15076-1-jiansheng.wu@unisoc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/8] Spi: sprd-adi: Getting panic reason before reboot | expand |
On 2023-08-15 10:34:19+0800, Jiansheng Wu wrote: > Registered adi_panic_event to panic_notifier_list, that is used to > get panic reason and judge restart causes before system reboot. > It's can improve reboot reasons from panic. > > Signed-off-by: Jiansheng Wu <jiansheng.wu@unisoc.com> > --- > drivers/spi/spi-sprd-adi.c | 46 ++++++++++++++++++++++++++++++++++---- > 1 file changed, 42 insertions(+), 4 deletions(-) > > diff --git a/drivers/spi/spi-sprd-adi.c b/drivers/spi/spi-sprd-adi.c > index 22e39c4c12c4..dd00d63a3cd0 100644 > --- a/drivers/spi/spi-sprd-adi.c > +++ b/drivers/spi/spi-sprd-adi.c > @@ -12,6 +12,7 @@ > #include <linux/module.h> > #include <linux/of.h> > #include <linux/of_device.h> > +#include <linux/panic_notifier.h> > #include <linux/platform_device.h> > #include <linux/reboot.h> > #include <linux/spi/spi.h> > @@ -128,6 +129,8 @@ > #define WDG_LOAD_MASK GENMASK(15, 0) > #define WDG_UNLOCK_KEY 0xe551 > > +#define PANIC_REASON_LEN_MAX 20 > + > struct sprd_adi_wdg { > u32 base; > u32 rst_sts; > @@ -155,6 +158,31 @@ struct sprd_adi { > const struct sprd_adi_data *data; > }; > > +static char *panic_reason; > +static int adi_panic_event(struct notifier_block *self, unsigned long val, void *reason) > +{ > + if (reason == NULL) > + return 0; > + > + if (strlen(reason) < PANIC_REASON_LEN_MAX) > + memcpy(panic_reason, reason, strlen(reason)); > + else > + memcpy(panic_reason, reason, PANIC_REASON_LEN_MAX); This will truncate the trailing '\0'. The string logic below will be invalid on a non-null-terminated byte array. strscpy() would avoid the issue. > + > + return 0; > +} > + > +static struct notifier_block adi_panic_event_nb = { > + .notifier_call = adi_panic_event, > + .priority = INT_MAX, > +}; > + > +static int adi_get_panic_reason_init(void) > +{ > + atomic_notifier_chain_register(&panic_notifier_list, &adi_panic_event_nb); > + return 0; > +} > + > static int sprd_adi_check_addr(struct sprd_adi *sadi, u32 reg) > { > if (reg >= sadi->data->slave_addr_size) { > @@ -378,9 +406,15 @@ static int sprd_adi_restart(struct notifier_block *this, unsigned long mode, > restart_handler); > u32 val, reboot_mode = 0; > > - if (!cmd) > - reboot_mode = HWRST_STATUS_NORMAL; > - else if (!strncmp(cmd, "recovery", 8)) > + if (!cmd) { > + if (strlen(panic_reason)) { > + reboot_mode = HWRST_STATUS_PANIC; > + if (strstr(panic_reason, "tospanic")) > + reboot_mode = HWRST_STATUS_SECURITY; > + } else { > + reboot_mode = HWRST_STATUS_NORMAL; > + } > + } else if (!strncmp(cmd, "recovery", 8)) > reboot_mode = HWRST_STATUS_RECOVERY; > else if (!strncmp(cmd, "alarm", 5)) > reboot_mode = HWRST_STATUS_ALARM; > @@ -520,6 +554,10 @@ static int sprd_adi_probe(struct platform_device *pdev) > u16 num_chipselect; > int ret; > > + panic_reason = devm_kzalloc(&pdev->dev, (sizeof(char))*PANIC_REASON_LEN_MAX, GFP_KERNEL); sizeof(char) is guaranteed to be 1 by the C standard. It seems weird to devm_alloc() something that will be stored in a static buffer. If multiple devices are bound to the driver the results will be weird. Also if the device is unbound the notifier won't be unregistered and panic_mode will point to freed memory. > + if (!panic_reason) > + return -ENOMEM; > + > if (!np) { > dev_err(&pdev->dev, "can not find the adi bus node\n"); > return -ENODEV; > @@ -573,7 +611,7 @@ static int sprd_adi_probe(struct platform_device *pdev) > } > > sprd_adi_hw_init(sadi); > - > + adi_get_panic_reason_init(); Why drop the empty line? > if (sadi->data->wdg_rst) > sadi->data->wdg_rst(sadi); > > -- > 2.17.1 >
On Tue, Aug 15, 2023 at 10:34:19AM +0800, Jiansheng Wu wrote: > + if (strlen(reason) < PANIC_REASON_LEN_MAX) > + memcpy(panic_reason, reason, strlen(reason)); > + else > + memcpy(panic_reason, reason, PANIC_REASON_LEN_MAX); There's length limited strcpy() variants for this.
diff --git a/drivers/spi/spi-sprd-adi.c b/drivers/spi/spi-sprd-adi.c index 22e39c4c12c4..dd00d63a3cd0 100644 --- a/drivers/spi/spi-sprd-adi.c +++ b/drivers/spi/spi-sprd-adi.c @@ -12,6 +12,7 @@ #include <linux/module.h> #include <linux/of.h> #include <linux/of_device.h> +#include <linux/panic_notifier.h> #include <linux/platform_device.h> #include <linux/reboot.h> #include <linux/spi/spi.h> @@ -128,6 +129,8 @@ #define WDG_LOAD_MASK GENMASK(15, 0) #define WDG_UNLOCK_KEY 0xe551 +#define PANIC_REASON_LEN_MAX 20 + struct sprd_adi_wdg { u32 base; u32 rst_sts; @@ -155,6 +158,31 @@ struct sprd_adi { const struct sprd_adi_data *data; }; +static char *panic_reason; +static int adi_panic_event(struct notifier_block *self, unsigned long val, void *reason) +{ + if (reason == NULL) + return 0; + + if (strlen(reason) < PANIC_REASON_LEN_MAX) + memcpy(panic_reason, reason, strlen(reason)); + else + memcpy(panic_reason, reason, PANIC_REASON_LEN_MAX); + + return 0; +} + +static struct notifier_block adi_panic_event_nb = { + .notifier_call = adi_panic_event, + .priority = INT_MAX, +}; + +static int adi_get_panic_reason_init(void) +{ + atomic_notifier_chain_register(&panic_notifier_list, &adi_panic_event_nb); + return 0; +} + static int sprd_adi_check_addr(struct sprd_adi *sadi, u32 reg) { if (reg >= sadi->data->slave_addr_size) { @@ -378,9 +406,15 @@ static int sprd_adi_restart(struct notifier_block *this, unsigned long mode, restart_handler); u32 val, reboot_mode = 0; - if (!cmd) - reboot_mode = HWRST_STATUS_NORMAL; - else if (!strncmp(cmd, "recovery", 8)) + if (!cmd) { + if (strlen(panic_reason)) { + reboot_mode = HWRST_STATUS_PANIC; + if (strstr(panic_reason, "tospanic")) + reboot_mode = HWRST_STATUS_SECURITY; + } else { + reboot_mode = HWRST_STATUS_NORMAL; + } + } else if (!strncmp(cmd, "recovery", 8)) reboot_mode = HWRST_STATUS_RECOVERY; else if (!strncmp(cmd, "alarm", 5)) reboot_mode = HWRST_STATUS_ALARM; @@ -520,6 +554,10 @@ static int sprd_adi_probe(struct platform_device *pdev) u16 num_chipselect; int ret; + panic_reason = devm_kzalloc(&pdev->dev, (sizeof(char))*PANIC_REASON_LEN_MAX, GFP_KERNEL); + if (!panic_reason) + return -ENOMEM; + if (!np) { dev_err(&pdev->dev, "can not find the adi bus node\n"); return -ENODEV; @@ -573,7 +611,7 @@ static int sprd_adi_probe(struct platform_device *pdev) } sprd_adi_hw_init(sadi); - + adi_get_panic_reason_init(); if (sadi->data->wdg_rst) sadi->data->wdg_rst(sadi);
Registered adi_panic_event to panic_notifier_list, that is used to get panic reason and judge restart causes before system reboot. It's can improve reboot reasons from panic. Signed-off-by: Jiansheng Wu <jiansheng.wu@unisoc.com> --- drivers/spi/spi-sprd-adi.c | 46 ++++++++++++++++++++++++++++++++++---- 1 file changed, 42 insertions(+), 4 deletions(-)