| Message ID | 1352962777-24407-6-git-send-email-wency@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
2012/11/15 15:59, Wen Congyang wrote: > We eject the memory device even if it is in use. It is very dangerous, > and it will cause the kernel to be panicked. > > CC: David Rientjes <rientjes@google.com> > CC: Jiang Liu <liuj97@gmail.com> > CC: Len Brown <len.brown@intel.com> > CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> > CC: Paul Mackerras <paulus@samba.org> > CC: Christoph Lameter <cl@linux.com> > Cc: Minchan Kim <minchan.kim@gmail.com> > CC: Andrew Morton <akpm@linux-foundation.org> > CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> > CC: Rafael J. Wysocki <rjw@sisk.pl> > CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> > --- Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Thanks, Yasuaki Ishimatsu > drivers/acpi/acpi_memhotplug.c | 42 +++++++++++++++++++++++++++++++++--------- > 1 file changed, 33 insertions(+), 9 deletions(-) > > diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c > index e52ad5d..f7e3007 100644 > --- a/drivers/acpi/acpi_memhotplug.c > +++ b/drivers/acpi/acpi_memhotplug.c > @@ -78,6 +78,7 @@ struct acpi_memory_info { > unsigned short caching; /* memory cache attribute */ > unsigned short write_protect; /* memory read/write attribute */ > unsigned int enabled:1; > + unsigned int failed:1; > }; > > struct acpi_memory_device { > @@ -257,9 +258,23 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) > node = memory_add_physaddr_to_nid(info->start_addr); > > result = add_memory(node, info->start_addr, info->length); > - if (result) > + > + /* > + * If the memory block has been used by the kernel, add_memory() > + * returns -EEXIST. If add_memory() returns the other error, it > + * means that this memory block is not used by the kernel. > + */ > + if (result && result != -EEXIST) { > + info->failed = 1; > continue; > - info->enabled = 1; > + } > + > + if (!result) > + info->enabled = 1; > + /* > + * Add num_enable even if add_memory() returns -EEXIST, so the > + * device is bound to this driver. > + */ > num_enabled++; > } > if (!num_enabled) { > @@ -280,21 +295,30 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) > > static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device) > { > - int result; > + int result = 0; > struct acpi_memory_info *info, *n; > > list_for_each_entry_safe(info, n, &mem_device->res_list, list) { > - if (info->enabled) { > - result = remove_memory(info->start_addr, info->length); > - if (result) > - return result; > - } > + if (info->failed) > + /* The kernel does not use this memory block */ > + continue; > + > + if (!info->enabled) > + /* > + * The kernel uses this memory block, but it may be not > + * managed by us. > + */ > + return -EBUSY; > + > + result = remove_memory(info->start_addr, info->length); > + if (result) > + return result; > > list_del(&info->list); > kfree(info); > } > > - return 0; > + return result; > } > > static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data) > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 15 Nov 2012, Wen Congyang wrote: > We eject the memory device even if it is in use. It is very dangerous, > and it will cause the kernel to be panicked. > > CC: David Rientjes <rientjes@google.com> > CC: Jiang Liu <liuj97@gmail.com> > CC: Len Brown <len.brown@intel.com> > CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> > CC: Paul Mackerras <paulus@samba.org> > CC: Christoph Lameter <cl@linux.com> > Cc: Minchan Kim <minchan.kim@gmail.com> > CC: Andrew Morton <akpm@linux-foundation.org> > CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> > CC: Rafael J. Wysocki <rjw@sisk.pl> > CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Thanks for adding the comment about why num_enabled is incremented for -EEXIST. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
2012/11/15 Wen Congyang <wency@cn.fujitsu.com> > > We eject the memory device even if it is in use. It is very dangerous, > and it will cause the kernel to be panicked. > > CC: David Rientjes <rientjes@google.com> > CC: Jiang Liu <liuj97@gmail.com> > CC: Len Brown <len.brown@intel.com> > CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> > CC: Paul Mackerras <paulus@samba.org> > CC: Christoph Lameter <cl@linux.com> > Cc: Minchan Kim <minchan.kim@gmail.com> > CC: Andrew Morton <akpm@linux-foundation.org> > CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> > CC: Rafael J. Wysocki <rjw@sisk.pl> > CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> > --- > drivers/acpi/acpi_memhotplug.c | 42 +++++++++++++++++++++++++++++++++--------- > 1 file changed, 33 insertions(+), 9 deletions(-) > > diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c > index e52ad5d..f7e3007 100644 > --- a/drivers/acpi/acpi_memhotplug.c > +++ b/drivers/acpi/acpi_memhotplug.c > @@ -78,6 +78,7 @@ struct acpi_memory_info { > unsigned short caching; /* memory cache attribute */ > unsigned short write_protect; /* memory read/write attribute */ > unsigned int enabled:1; > + unsigned int failed:1; > }; > > struct acpi_memory_device { > @@ -257,9 +258,23 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) > node = memory_add_physaddr_to_nid(info->start_addr); > > result = add_memory(node, info->start_addr, info->length); > - if (result) > + > + /* > + * If the memory block has been used by the kernel, add_memory() > + * returns -EEXIST. If add_memory() returns the other error, it > + * means that this memory block is not used by the kernel. > + */ > + if (result && result != -EEXIST) { > + info->failed = 1; > continue; > - info->enabled = 1; > + } > + > + if (!result) > + info->enabled = 1; Hi Congyang, If a memory device booting with the system, the info->enable will equal to 0, and can not be hot-removed in acpi_memory_remove_memory(), right? Thanks, Jianguo Wu > > + /* > + * Add num_enable even if add_memory() returns -EEXIST, so the > + * device is bound to this driver. > + */ > num_enabled++; > } > if (!num_enabled) { > @@ -280,21 +295,30 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) > > static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device) > { > - int result; > + int result = 0; > struct acpi_memory_info *info, *n; > > list_for_each_entry_safe(info, n, &mem_device->res_list, list) { > - if (info->enabled) { > - result = remove_memory(info->start_addr, info->length); > - if (result) > - return result; > - } > + if (info->failed) > + /* The kernel does not use this memory block */ > + continue; > + > + if (!info->enabled) > + /* > + * The kernel uses this memory block, but it may be not > + * managed by us. > + */ > + return -EBUSY; > + > + result = remove_memory(info->start_addr, info->length); > + if (result) > + return result; > > list_del(&info->list); > kfree(info); > } > > - return 0; > + return result; > } > > static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data) > -- > 1.8.0 > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c index e52ad5d..f7e3007 100644 --- a/drivers/acpi/acpi_memhotplug.c +++ b/drivers/acpi/acpi_memhotplug.c @@ -78,6 +78,7 @@ struct acpi_memory_info { unsigned short caching; /* memory cache attribute */ unsigned short write_protect; /* memory read/write attribute */ unsigned int enabled:1; + unsigned int failed:1; }; struct acpi_memory_device { @@ -257,9 +258,23 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) node = memory_add_physaddr_to_nid(info->start_addr); result = add_memory(node, info->start_addr, info->length); - if (result) + + /* + * If the memory block has been used by the kernel, add_memory() + * returns -EEXIST. If add_memory() returns the other error, it + * means that this memory block is not used by the kernel. + */ + if (result && result != -EEXIST) { + info->failed = 1; continue; - info->enabled = 1; + } + + if (!result) + info->enabled = 1; + /* + * Add num_enable even if add_memory() returns -EEXIST, so the + * device is bound to this driver. + */ num_enabled++; } if (!num_enabled) { @@ -280,21 +295,30 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device) { - int result; + int result = 0; struct acpi_memory_info *info, *n; list_for_each_entry_safe(info, n, &mem_device->res_list, list) { - if (info->enabled) { - result = remove_memory(info->start_addr, info->length); - if (result) - return result; - } + if (info->failed) + /* The kernel does not use this memory block */ + continue; + + if (!info->enabled) + /* + * The kernel uses this memory block, but it may be not + * managed by us. + */ + return -EBUSY; + + result = remove_memory(info->start_addr, info->length); + if (result) + return result; list_del(&info->list); kfree(info); } - return 0; + return result; } static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
We eject the memory device even if it is in use. It is very dangerous, and it will cause the kernel to be panicked. CC: David Rientjes <rientjes@google.com> CC: Jiang Liu <liuj97@gmail.com> CC: Len Brown <len.brown@intel.com> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: Paul Mackerras <paulus@samba.org> CC: Christoph Lameter <cl@linux.com> Cc: Minchan Kim <minchan.kim@gmail.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> CC: Rafael J. Wysocki <rjw@sisk.pl> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> --- drivers/acpi/acpi_memhotplug.c | 42 +++++++++++++++++++++++++++++++++--------- 1 file changed, 33 insertions(+), 9 deletions(-)