From: Xiongfeng Wang wangxiongfeng2@huawei.com
Offering: HULK hulk inclusion category: bugfix bugzilla: 174524 https://gitee.com/openeuler/kernel/issues/I4DDEL
-------------------------------------------------
When I added might_sleep() in down_timeout(), I got the following Calltrace:
[ 8.775671] BUG: sleeping function called from invalid context at kernel/locking/semaphore.c:160 [ 8.777070] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 14, name: cpuhp/0 [ 8.778474] CPU: 0 PID: 14 Comm: cpuhp/0 Not tainted 5.10.0-06616-g1fcfee258bd9-dirty #416 [ 8.782067] Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 [ 8.783452] Call trace: [ 8.783878] dump_backtrace+0x0/0x1c0 [ 8.784512] show_stack+0x18/0x68 [ 8.784976] dump_stack+0xd8/0x134 [ 8.785428] ___might_sleep+0x108/0x170 [ 8.785928] __might_sleep+0x54/0x90 [ 8.786425] down_timeout+0x30/0x88 [ 8.786918] acpi_os_wait_semaphore+0x70/0xb8 [ 8.787483] acpi_ut_acquire_mutex+0x4c/0xb8 [ 8.788016] acpi_get_table+0x38/0xc4 [ 8.788521] acpi_find_last_cache_level+0x94/0x178 [ 8.789088] _init_cache_level+0xd0/0xe0 [ 8.789563] generic_exec_single+0xa0/0x100 [ 8.790122] smp_call_function_single+0x160/0x1e0 [ 8.790714] init_cache_level+0x38/0x60 [ 8.791247] cacheinfo_cpu_online+0x30/0x898 [ 8.791880] cpuhp_invoke_callback+0x88/0x258 [ 8.792707] cpuhp_thread_fun+0xd8/0x170 [ 8.793231] smpboot_thread_fn+0x194/0x290 [ 8.793838] kthread+0x15c/0x160 [ 8.794273] ret_from_fork+0x10/0x34
It is because generic_exec_single() will disable local irq before calling _init_cache_level(). _init_cache_level() use acpi_get_table() to get the PPTT table, but this function could schedule out.
To fix this issue, we use a static pointer to record the mapped PPTT table in the first beginning. Later, we use that pointer to reference the PPTT table in acpi_find_last_cache_level(). We also modify other functions in pptt.c to use the pointer to reference PPTT table.
Signed-off-by: Xiongfeng Wang wangxiongfeng2@huawei.com Reviewed-by: Hanjun Guo guohanjun@huawei.com Signed-off-by: Chen Jun chenjun102@huawei.com --- arch/arm64/kernel/topology.c | 6 ++- drivers/acpi/pptt.c | 83 +++++++++++++++--------------------- include/linux/acpi.h | 1 + 3 files changed, 41 insertions(+), 49 deletions(-)
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 7a487976ce8b..19cedf882a6b 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -90,11 +90,15 @@ static bool __init acpi_cpu_is_threaded(int cpu) */ int __init parse_acpi_topology(void) { - int cpu, topology_id; + int cpu, topology_id, ret;
if (acpi_disabled) return 0;
+ ret = acpi_pptt_init(); + if (ret) + return ret; + for_each_possible_cpu(cpu) { int i, cache_id;
diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index 8eddddc5afcc..20bd584f2516 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -21,6 +21,9 @@ #include <linux/cacheinfo.h> #include <acpi/processor.h>
+/* Root pointer to the mapped PPTT table */ +static struct acpi_table_header *pptt_table; + static struct acpi_subtable_header *fetch_pptt_subtable(struct acpi_table_header *table_hdr, u32 pptt_ref) { @@ -667,19 +670,13 @@ static int topology_get_acpi_cpu_tag(struct acpi_table_header *table,
static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) { - struct acpi_table_header *table; - acpi_status status; int retval;
- status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); + if (!pptt_table) return -ENOENT; - } - retval = topology_get_acpi_cpu_tag(table, cpu, level, flag); + retval = topology_get_acpi_cpu_tag(pptt_table, cpu, level, flag); pr_debug("Topology Setup ACPI CPU %d, level %d ret = %d\n", cpu, level, retval); - acpi_put_table(table);
return retval; } @@ -699,26 +696,19 @@ static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) */ static int check_acpi_cpu_flag(unsigned int cpu, int rev, u32 flag) { - struct acpi_table_header *table; - acpi_status status; u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); struct acpi_pptt_processor *cpu_node = NULL; int ret = -ENOENT;
- status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); - return ret; - } + if (!pptt_table) + return -ENOENT;
- if (table->revision >= rev) - cpu_node = acpi_find_processor_node(table, acpi_cpu_id); + if (pptt_table->revision >= rev) + cpu_node = acpi_find_processor_node(pptt_table, acpi_cpu_id);
if (cpu_node) ret = (cpu_node->flags & flag) != 0;
- acpi_put_table(table); - return ret; }
@@ -735,20 +725,14 @@ static int check_acpi_cpu_flag(unsigned int cpu, int rev, u32 flag) int acpi_find_last_cache_level(unsigned int cpu) { u32 acpi_cpu_id; - struct acpi_table_header *table; int number_of_levels = 0; - acpi_status status;
pr_debug("Cache Setup find last level CPU=%d\n", cpu);
acpi_cpu_id = get_acpi_id_for_cpu(cpu); - status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); - } else { - number_of_levels = acpi_find_cache_levels(table, acpi_cpu_id); - acpi_put_table(table); - } + if (pptt_table) + number_of_levels = acpi_find_cache_levels(pptt_table, acpi_cpu_id); + pr_debug("Cache Setup find last level level=%d\n", number_of_levels);
return number_of_levels; @@ -769,21 +753,14 @@ int acpi_find_last_cache_level(unsigned int cpu) */ int cache_setup_acpi(unsigned int cpu) { - struct acpi_table_header *table; - acpi_status status; - pr_debug("Cache Setup ACPI CPU %d\n", cpu);
- status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); + if (!pptt_table) return -ENOENT; - }
- cache_setup_acpi_cpu(table, cpu); - acpi_put_table(table); + cache_setup_acpi_cpu(pptt_table, cpu);
- return status; + return 0; }
/** @@ -835,27 +812,20 @@ int find_acpi_cpu_topology(unsigned int cpu, int level) */ int find_acpi_cpu_cache_topology(unsigned int cpu, int level) { - struct acpi_table_header *table; struct acpi_pptt_cache *found_cache; - acpi_status status; u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); struct acpi_pptt_processor *cpu_node = NULL; int ret = -1;
- status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); - if (ACPI_FAILURE(status)) { - acpi_pptt_warn_missing(); + if (!pptt_table) return -ENOENT; - }
- found_cache = acpi_find_cache_node(table, acpi_cpu_id, + found_cache = acpi_find_cache_node(pptt_table, acpi_cpu_id, CACHE_TYPE_UNIFIED, level, &cpu_node); if (found_cache) - ret = ACPI_PTR_DIFF(cpu_node, table); - - acpi_put_table(table); + ret = ACPI_PTR_DIFF(cpu_node, pptt_table);
return ret; } @@ -904,3 +874,20 @@ int find_acpi_cpu_topology_hetero_id(unsigned int cpu) return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, ACPI_PPTT_ACPI_IDENTICAL); } + +int __init acpi_pptt_init(void) +{ + acpi_status status; + + /* + * pptt_table will be used at runtime after acpi_pptt_init, so we don't + * need to call acpi_put_table() to release the PPTT table mapping. + */ + status = acpi_get_table(ACPI_SIG_PPTT, 0, &pptt_table); + if (ACPI_FAILURE(status)) { + acpi_pptt_warn_missing(); + return -ENOENT; + } + + return 0; +} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index f43dba853c25..a3db177329c2 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1347,6 +1347,7 @@ static inline int lpit_read_residency_count_address(u64 *address) #endif
#ifdef CONFIG_ACPI_PPTT +int acpi_pptt_init(void); int acpi_pptt_cpu_is_thread(unsigned int cpu); int find_acpi_cpu_topology(unsigned int cpu, int level); int find_acpi_cpu_topology_package(unsigned int cpu);