| Message ID | 20180921221705.6478-16-james.morse@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | APEI in_nmi() rework | expand |
On Fri, Sep 21, 2018 at 11:17:02PM +0100, James Morse wrote: > Each struct ghes has an worst-case sized buffer for storing the > estatus. If an error is being processed by ghes_proc() in process > context this buffer will be in use. If the error source then triggers > an NMI-like notification, the same buffer will be used by > _in_nmi_notify_one() to stage the estatus data, before > __process_error() copys it into a queued estatus entry. > > Merge __process_error()s work into _in_nmi_notify_one() so that > the queued estatus entry is used from the beginning. Use the > ghes_peek_estatus() so we know how much memory to allocate from > the ghes_estatus_pool before we read the records. > > Reported-by: Borislav Petkov <bp@suse.de> > Signed-off-by: James Morse <james.morse@arm.com> > --- > drivers/acpi/apei/ghes.c | 45 ++++++++++++++++++++-------------------- > 1 file changed, 22 insertions(+), 23 deletions(-) > > diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c > index 055176ed68ac..a0c10b60ad44 100644 > --- a/drivers/acpi/apei/ghes.c > +++ b/drivers/acpi/apei/ghes.c > @@ -722,40 +722,32 @@ static void ghes_print_queued_estatus(void) > } > } > > -/* Save estatus for further processing in IRQ context */ > -static void __process_error(struct ghes *ghes, > - struct acpi_hest_generic_status *ghes_estatus) > +static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) > { > + u64 buf_paddr; > + int sev, rc = 0; > u32 len, node_len; > struct ghes_estatus_node *estatus_node; > struct acpi_hest_generic_status *estatus; Please sort function local variables declaration in a reverse christmas tree order: <type> longest_variable_name; <type> shorter_var_name; <type> even_shorter; <type> i; > > - if (ghes_estatus_cached(ghes_estatus)) > - return; > + rc = ghes_peek_estatus(ghes, fixmap_idx, &buf_paddr, &len); Oh ok, maybe not prefix it with "__" - we're using it somewhere else. > + if (rc) > + return rc; > > - len = cper_estatus_len(ghes_estatus); > node_len = GHES_ESTATUS_NODE_LEN(len); > > estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); > if (!estatus_node) > - return; > + return -ENOMEM; > > estatus_node->ghes = ghes; > estatus_node->generic = ghes->generic; > estatus = GHES_ESTATUS_FROM_NODE(estatus_node); > - memcpy(estatus, ghes_estatus, len); > - llist_add(&estatus_node->llnode, &ghes_estatus_llist); > -} > - > -static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) > -{ > - int sev; > - u64 buf_paddr; > - struct acpi_hest_generic_status *estatus = ghes->estatus; > > - if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { > + if (__ghes_read_estatus(estatus, buf_paddr, len, fixmap_idx)) { > ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); > - return -ENOENT; > + rc = -ENOENT; > + goto no_work; > } > > sev = ghes_severity(estatus->error_severity); > @@ -764,13 +756,20 @@ static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) > __ghes_panic(ghes, estatus); > } > > - if (!buf_paddr) > - return 0; > - > - __process_error(ghes, estatus); > ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); > > - return 0; > + if (!buf_paddr || ghes_estatus_cached(estatus)) > + goto no_work; > + > + llist_add(&estatus_node->llnode, &ghes_estatus_llist); > + > + return rc; > + > +no_work: > + gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, > + node_len); Yeah, let it stick out.
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 055176ed68ac..a0c10b60ad44 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -722,40 +722,32 @@ static void ghes_print_queued_estatus(void) } } -/* Save estatus for further processing in IRQ context */ -static void __process_error(struct ghes *ghes, - struct acpi_hest_generic_status *ghes_estatus) +static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) { + u64 buf_paddr; + int sev, rc = 0; u32 len, node_len; struct ghes_estatus_node *estatus_node; struct acpi_hest_generic_status *estatus; - if (ghes_estatus_cached(ghes_estatus)) - return; + rc = ghes_peek_estatus(ghes, fixmap_idx, &buf_paddr, &len); + if (rc) + return rc; - len = cper_estatus_len(ghes_estatus); node_len = GHES_ESTATUS_NODE_LEN(len); estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); if (!estatus_node) - return; + return -ENOMEM; estatus_node->ghes = ghes; estatus_node->generic = ghes->generic; estatus = GHES_ESTATUS_FROM_NODE(estatus_node); - memcpy(estatus, ghes_estatus, len); - llist_add(&estatus_node->llnode, &ghes_estatus_llist); -} - -static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) -{ - int sev; - u64 buf_paddr; - struct acpi_hest_generic_status *estatus = ghes->estatus; - if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + if (__ghes_read_estatus(estatus, buf_paddr, len, fixmap_idx)) { ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); - return -ENOENT; + rc = -ENOENT; + goto no_work; } sev = ghes_severity(estatus->error_severity); @@ -764,13 +756,20 @@ static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) __ghes_panic(ghes, estatus); } - if (!buf_paddr) - return 0; - - __process_error(ghes, estatus); ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); - return 0; + if (!buf_paddr || ghes_estatus_cached(estatus)) + goto no_work; + + llist_add(&estatus_node->llnode, &ghes_estatus_llist); + + return rc; + +no_work: + gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, + node_len); + + return rc; } static int ghes_estatus_queue_notified(struct list_head *rcu_list,
Each struct ghes has an worst-case sized buffer for storing the estatus. If an error is being processed by ghes_proc() in process context this buffer will be in use. If the error source then triggers an NMI-like notification, the same buffer will be used by _in_nmi_notify_one() to stage the estatus data, before __process_error() copys it into a queued estatus entry. Merge __process_error()s work into _in_nmi_notify_one() so that the queued estatus entry is used from the beginning. Use the ghes_peek_estatus() so we know how much memory to allocate from the ghes_estatus_pool before we read the records. Reported-by: Borislav Petkov <bp@suse.de> Signed-off-by: James Morse <james.morse@arm.com> --- drivers/acpi/apei/ghes.c | 45 ++++++++++++++++++++-------------------- 1 file changed, 22 insertions(+), 23 deletions(-)