If vm_map_ram(page, 0, 0) would cause panic by vmap_pages_range_noflush, so
change IS_ERR to IS_ERR_OR_NULL to fix this.
Signed-off-by: Hailong.Liu <[email protected]>
---
mm/vmalloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index d12a17fc0c17..109732006cf7 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2387,7 +2387,7 @@ void *vm_map_ram(struct page **pages, unsigned int
count, int node)
if (likely(count <= VMAP_MAX_ALLOC)) {
mem = vb_alloc(size, GFP_KERNEL);
- if (IS_ERR(mem))
+ if (IS_ERR_OR_NULL(mem))
return NULL;
addr = (unsigned long)mem;
} else {
--
2.34.1
On Wed, Feb 28, 2024 at 10:34 PM Barry Song <[email protected]> wrote:
>
> On Wed, Feb 28, 2024 at 9:51 PM 刘海龙(LaoLiu) <[email protected]> wrote:
> >
> > If vm_map_ram(page, 0, 0) would cause panic by vmap_pages_range_noflush, so
> > change IS_ERR to IS_ERR_OR_NULL to fix this.
> >
> > Signed-off-by: Hailong.Liu <[email protected]>
> > ---
> > mm/vmalloc.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> > index d12a17fc0c17..109732006cf7 100644
> > --- a/mm/vmalloc.c
> > +++ b/mm/vmalloc.c
> > @@ -2387,7 +2387,7 @@ void *vm_map_ram(struct page **pages, unsigned int
> > count, int node)
> >
> > if (likely(count <= VMAP_MAX_ALLOC)) {
> > mem = vb_alloc(size, GFP_KERNEL);
> > - if (IS_ERR(mem))
> > + if (IS_ERR_OR_NULL(mem))
>
> it seems the only case for vb_alloc to return NULL is size = 0, isn't
> it a bug of
> caller?
what about the below?
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 25a8df497255..640157221c95 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2834,6 +2834,9 @@ void *vm_map_ram(struct page **pages, unsigned
int count, int node)
unsigned long addr;
void *mem;
+ if (unlikely(count == 0))
+ return NULL;
+
if (likely(count <= VMAP_MAX_ALLOC)) {
mem = vb_alloc(size, GFP_KERNEL);
if (IS_ERR(mem))
>
> > return NULL;
> > addr = (unsigned long)mem;
> > } else {
> > --
> > 2.34.1
Thanks
Barry
On Wed, Feb 28, 2024 at 9:51 PM 刘海龙(LaoLiu) <[email protected]> wrote:
>
> If vm_map_ram(page, 0, 0) would cause panic by vmap_pages_range_noflush, so
> change IS_ERR to IS_ERR_OR_NULL to fix this.
>
> Signed-off-by: Hailong.Liu <[email protected]>
> ---
> mm/vmalloc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index d12a17fc0c17..109732006cf7 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -2387,7 +2387,7 @@ void *vm_map_ram(struct page **pages, unsigned int
> count, int node)
>
> if (likely(count <= VMAP_MAX_ALLOC)) {
> mem = vb_alloc(size, GFP_KERNEL);
> - if (IS_ERR(mem))
> + if (IS_ERR_OR_NULL(mem))
it seems the only case for vb_alloc to return NULL is size = 0, isn't
it a bug of
caller?
> return NULL;
> addr = (unsigned long)mem;
> } else {
> --
> 2.34.1
Thanks
Barry
On 2024/2/28 17:34, Barry Song wrote:
> On Wed, Feb 28, 2024 at 9:51 PM 刘海龙(LaoLiu) <[email protected]> wrote:
>>
>> If vm_map_ram(page, 0, 0) would cause panic by vmap_pages_range_noflush, so
>> change IS_ERR to IS_ERR_OR_NULL to fix this.
>>
>> Signed-off-by: Hailong.Liu <[email protected]>
>> ---
>> mm/vmalloc.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
>> index d12a17fc0c17..109732006cf7 100644
>> --- a/mm/vmalloc.c
>> +++ b/mm/vmalloc.c
>> @@ -2387,7 +2387,7 @@ void *vm_map_ram(struct page **pages, unsigned int
>> count, int node)
>>
>> if (likely(count <= VMAP_MAX_ALLOC)) {
>> mem = vb_alloc(size, GFP_KERNEL);
>> - if (IS_ERR(mem))
>> + if (IS_ERR_OR_NULL(mem))
>
> it seems the only case for vb_alloc to return NULL is size = 0, isn't
> it a bug of
> caller?
vb_alloc had already checked the size == 0, so it should be return NULL
to caller or not panic here.
In fact, we encounter z_erofs_lz4_decompress issue.
[54032.383633][T25392] vmap_pages_range_noflush+0x790/0x8f8
[54032.383637][T25392] vm_map_ram+0x1c8/0x10b0
[54032.383642][T25392] z_erofs_lz4_decompress+0x60/0x1e8
[54032.383648][T25392] z_erofs_decompress_pcluster+0x624/0x9fc
[54032.383653][T25392] z_erofs_decompress_kickoff+0x18c/0x224
[54032.383658][T25392] z_erofs_decompressqueue_endio+0x1a8/0x1e0
[54032.383663][T25392] bio_endio+0x188/0x47c
[54032.383667][T25392] clone_endio+0x1a0/0x550
[54032.383674][T25392] bio_endio+0x14c/0x47c
[54032.383678][T25392] verity_work.60258+0x7c/0x13c
[54032.383682][T25392] process_one_work+0x1b8/0xa98
[54032.383687][T25392] worker_thread+0x160/0x6c0
[54032.383691][T25392] kthread+0x15c/0x1d0
[54032.383696][T25392] ret_from_fork+0x10/0x20
z_erofs_lz4_decompress has checked the return value, so it's reasonable
to return NULL if size == 0.
Brs,
Hailong.
>
>> return NULL;
>> addr = (unsigned long)mem;
>> } else {
>> --
>> 2.34.1
>
> Thanks
> Barry
On Wed, Feb 28, 2024 at 11:02 PM 刘海龙(LaoLiu) <[email protected]> wrote:
>
> On 2024/2/28 17:34, Barry Song wrote:
> > On Wed, Feb 28, 2024 at 9:51 PM 刘海龙(LaoLiu) <[email protected]> wrote:
> >>
> >> If vm_map_ram(page, 0, 0) would cause panic by vmap_pages_range_noflush, so
> >> change IS_ERR to IS_ERR_OR_NULL to fix this.
> >>
> >> Signed-off-by: Hailong.Liu <[email protected]>
> >> ---
> >> mm/vmalloc.c | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> >> index d12a17fc0c17..109732006cf7 100644
> >> --- a/mm/vmalloc.c
> >> +++ b/mm/vmalloc.c
> >> @@ -2387,7 +2387,7 @@ void *vm_map_ram(struct page **pages, unsigned int
> >> count, int node)
> >>
> >> if (likely(count <= VMAP_MAX_ALLOC)) {
> >> mem = vb_alloc(size, GFP_KERNEL);
> >> - if (IS_ERR(mem))
> >> + if (IS_ERR_OR_NULL(mem))
> >
> > it seems the only case for vb_alloc to return NULL is size = 0, isn't
> > it a bug of
> > caller?
> vb_alloc had already checked the size == 0, so it should be return NULL
> to caller or not panic here.
>
> In fact, we encounter z_erofs_lz4_decompress issue.
>
> [54032.383633][T25392] vmap_pages_range_noflush+0x790/0x8f8
> [54032.383637][T25392] vm_map_ram+0x1c8/0x10b0
> [54032.383642][T25392] z_erofs_lz4_decompress+0x60/0x1e8
> [54032.383648][T25392] z_erofs_decompress_pcluster+0x624/0x9fc
> [54032.383653][T25392] z_erofs_decompress_kickoff+0x18c/0x224
> [54032.383658][T25392] z_erofs_decompressqueue_endio+0x1a8/0x1e0
> [54032.383663][T25392] bio_endio+0x188/0x47c
> [54032.383667][T25392] clone_endio+0x1a0/0x550
> [54032.383674][T25392] bio_endio+0x14c/0x47c
> [54032.383678][T25392] verity_work.60258+0x7c/0x13c
> [54032.383682][T25392] process_one_work+0x1b8/0xa98
> [54032.383687][T25392] worker_thread+0x160/0x6c0
> [54032.383691][T25392] kthread+0x15c/0x1d0
> [54032.383696][T25392] ret_from_fork+0x10/0x20
>
> z_erofs_lz4_decompress has checked the return value, so it's reasonable
> to return NULL if size == 0.
I agree. but there is no reason to activate a WARN_ON in vb_alloc as
obviously it doesn't like it. so fix it earlier.
I even feel z_erofs_lz4_decompress is a better place than vm_map_ram
according to your description. but at least vm_map_ram is better than
checking a vb_alloc's ret after it gives a parameter obviously hated and
causes complaints.
>
> Brs,
> Hailong.
> >
> >> return NULL;
> >> addr = (unsigned long)mem;
> >> } else {
> >> --
> >> 2.34.1
> >
Thanks
Barry