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* [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
@ 2022-07-12 12:35 Dan Carpenter
  2022-07-12 13:46 ` Zach O'Keefe
  2022-07-12 17:02 ` Yang Shi
  0 siblings, 2 replies; 5+ messages in thread
From: Dan Carpenter @ 2022-07-12 12:35 UTC (permalink / raw)
  To: kbuild, Zach O'Keefe
  Cc: lkp, kbuild-all, linux-kernel, Andrew Morton,
	Linux Memory Management List

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
head:   0e9f775fb0b4adf1a4ef50ea156ead09a0fc5194
commit: 9f626ffb1d1c5c26b4a8e0fdffec784a5f773274 [284/293] mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220710/202207100715.TBIYQ4fc-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'

vim +/cc +2409 mm/khugepaged.c

9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2387  int madvise_collapse(struct vm_area_struct *vma, struct vm_area_struct **prev,
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2388  		     unsigned long start, unsigned long end)
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2389  {
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2390  	struct collapse_control *cc;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2391  	struct mm_struct *mm = vma->vm_mm;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2392  	unsigned long hstart, hend, addr;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2393  	int thps = 0, last_fail = SCAN_FAIL;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2394  	bool mmap_locked = true;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2395  
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2396  	BUG_ON(vma->vm_start > start);
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2397  	BUG_ON(vma->vm_end < end);
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2398  
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2399  	cc = kmalloc(sizeof(*cc), GFP_KERNEL);
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2400  	if (!cc)
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2401  		return -ENOMEM;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2402  	cc->is_khugepaged = false;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2403  	cc->last_target_node = NUMA_NO_NODE;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2404  
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2405  	*prev = vma;
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2406  
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2407  	/* TODO: Support file/shmem */
9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2408  	if (!vma->anon_vma || !vma_is_anonymous(vma))
9f626ffb1d1c5c Zach O'Keefe 2022-07-06 @2409  		return -EINVAL;

kfree(cc);?


-- 
0-DAY CI Kernel Test Service
https://01.org/lkp



^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
  2022-07-12 12:35 [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc' Dan Carpenter
@ 2022-07-12 13:46 ` Zach O'Keefe
  2022-07-12 17:02 ` Yang Shi
  1 sibling, 0 replies; 5+ messages in thread
From: Zach O'Keefe @ 2022-07-12 13:46 UTC (permalink / raw)
  To: Dan Carpenter
  Cc: kbuild, lkp, kbuild-all, linux-kernel, Andrew Morton,
	Linux Memory Management List

On Jul 12 15:35, Dan Carpenter wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
> head:   0e9f775fb0b4adf1a4ef50ea156ead09a0fc5194
> commit: 9f626ffb1d1c5c26b4a8e0fdffec784a5f773274 [284/293] mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse
> config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220710/202207100715.TBIYQ4fc-lkp@intel.com/config)
> compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
> 
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> 
> smatch warnings:
> mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
> 
> vim +/cc +2409 mm/khugepaged.c
> 
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2387  int madvise_collapse(struct vm_area_struct *vma, struct vm_area_struct **prev,
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2388  		     unsigned long start, unsigned long end)
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2389  {
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2390  	struct collapse_control *cc;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2391  	struct mm_struct *mm = vma->vm_mm;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2392  	unsigned long hstart, hend, addr;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2393  	int thps = 0, last_fail = SCAN_FAIL;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2394  	bool mmap_locked = true;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2395  
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2396  	BUG_ON(vma->vm_start > start);
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2397  	BUG_ON(vma->vm_end < end);
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2398  
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2399  	cc = kmalloc(sizeof(*cc), GFP_KERNEL);
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2400  	if (!cc)
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2401  		return -ENOMEM;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2402  	cc->is_khugepaged = false;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2403  	cc->last_target_node = NUMA_NO_NODE;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2404  
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2405  	*prev = vma;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2406  
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2407  	/* TODO: Support file/shmem */
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2408  	if (!vma->anon_vma || !vma_is_anonymous(vma))
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06 @2409  		return -EINVAL;
> 
> kfree(cc);?
> 
> 
> -- 
> 0-DAY CI Kernel Test Service
> https://01.org/lkp
> 

Yikes. Glad this was caught - my apologies here.

Thanks Dan/lkp!


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
  2022-07-12 12:35 [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc' Dan Carpenter
  2022-07-12 13:46 ` Zach O'Keefe
@ 2022-07-12 17:02 ` Yang Shi
  2022-07-13 14:24   ` Zach O'Keefe
  1 sibling, 1 reply; 5+ messages in thread
From: Yang Shi @ 2022-07-12 17:02 UTC (permalink / raw)
  To: Dan Carpenter
  Cc: kbuild, Zach O'Keefe, kernel test robot, kbuild-all,
	Linux Kernel Mailing List, Andrew Morton,
	Linux Memory Management List

On Tue, Jul 12, 2022 at 5:36 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
> head:   0e9f775fb0b4adf1a4ef50ea156ead09a0fc5194
> commit: 9f626ffb1d1c5c26b4a8e0fdffec784a5f773274 [284/293] mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse
> config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220710/202207100715.TBIYQ4fc-lkp@intel.com/config)
> compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
>
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
>
> smatch warnings:
> mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
>
> vim +/cc +2409 mm/khugepaged.c
>
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2387  int madvise_collapse(struct vm_area_struct *vma, struct vm_area_struct **prev,
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2388                 unsigned long start, unsigned long end)
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2389  {
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2390    struct collapse_control *cc;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2391    struct mm_struct *mm = vma->vm_mm;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2392    unsigned long hstart, hend, addr;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2393    int thps = 0, last_fail = SCAN_FAIL;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2394    bool mmap_locked = true;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2395
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2396    BUG_ON(vma->vm_start > start);
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2397    BUG_ON(vma->vm_end < end);
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2398
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2399    cc = kmalloc(sizeof(*cc), GFP_KERNEL);
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2400    if (!cc)
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2401            return -ENOMEM;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2402    cc->is_khugepaged = false;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2403    cc->last_target_node = NUMA_NO_NODE;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2404
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2405    *prev = vma;
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2406
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2407    /* TODO: Support file/shmem */
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2408    if (!vma->anon_vma || !vma_is_anonymous(vma))
> 9f626ffb1d1c5c Zach O'Keefe 2022-07-06 @2409            return -EINVAL;

It seems better to move the cc kmalloc after the anonymous vma check?

>
> kfree(cc);?
>
>
> --
> 0-DAY CI Kernel Test Service
> https://01.org/lkp
>
>


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
  2022-07-12 17:02 ` Yang Shi
@ 2022-07-13 14:24   ` Zach O'Keefe
  2022-07-13 19:04     ` Yang Shi
  0 siblings, 1 reply; 5+ messages in thread
From: Zach O'Keefe @ 2022-07-13 14:24 UTC (permalink / raw)
  To: Yang Shi
  Cc: Dan Carpenter, kbuild, kernel test robot, kbuild-all,
	Linux Kernel Mailing List, Andrew Morton,
	Linux Memory Management List

On Jul 12 10:02, Yang Shi wrote:
> On Tue, Jul 12, 2022 at 5:36 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> >
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
> > head:   0e9f775fb0b4adf1a4ef50ea156ead09a0fc5194
> > commit: 9f626ffb1d1c5c26b4a8e0fdffec784a5f773274 [284/293] mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse
> > config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220710/202207100715.TBIYQ4fc-lkp@intel.com/config)
> > compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
> >
> > If you fix the issue, kindly add following tag where applicable
> > Reported-by: kernel test robot <lkp@intel.com>
> > Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> >
> > smatch warnings:
> > mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
> >
> > vim +/cc +2409 mm/khugepaged.c
> >
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2387  int madvise_collapse(struct vm_area_struct *vma, struct vm_area_struct **prev,
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2388                 unsigned long start, unsigned long end)
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2389  {
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2390    struct collapse_control *cc;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2391    struct mm_struct *mm = vma->vm_mm;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2392    unsigned long hstart, hend, addr;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2393    int thps = 0, last_fail = SCAN_FAIL;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2394    bool mmap_locked = true;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2395
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2396    BUG_ON(vma->vm_start > start);
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2397    BUG_ON(vma->vm_end < end);
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2398
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2399    cc = kmalloc(sizeof(*cc), GFP_KERNEL);
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2400    if (!cc)
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2401            return -ENOMEM;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2402    cc->is_khugepaged = false;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2403    cc->last_target_node = NUMA_NO_NODE;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2404
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2405    *prev = vma;
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2406
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2407    /* TODO: Support file/shmem */
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2408    if (!vma->anon_vma || !vma_is_anonymous(vma))
> > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06 @2409            return -EINVAL;
> 
> It seems better to move the cc kmalloc after the anonymous vma check?
>

Agreed - something I only noticed when fixing this. I've cleaned up some
ordering here, now looks like:

---8<---
	BUG_ON(vma->vm_start > start);
	BUG_ON(vma->vm_end < end);

	*prev = vma;

        /* TODO: Support file/shmem */
        if (!vma->anon_vma || !vma_is_anonymous(vma))
                return -EINVAL;

	if (!hugepage_vma_check(vma, vma->vm_flags, false, false, false))
		return -EINVAL;

	cc = kmalloc(sizeof(*cc), GFP_KERNEL);
	if (!cc)
		return -ENOMEM;
	cc->is_khugepaged = false;
	cc->last_target_node = NUMA_NO_NODE;

	mmgrab(mm);
	lru_add_drain_all();

	hstart = (start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
	hend = end & HPAGE_PMD_MASK;

	for (addr = hstart; addr < hend; addr += HPAGE_PMD_SIZE) {
---8<---
out_nolock:
	mmap_assert_locked(mm);
	mmdrop(mm);
	kfree(cc);
---8<---

> >
> > kfree(cc);?
> >
> >
> > --
> > 0-DAY CI Kernel Test Service
> > https://01.org/lkp
> >
> >


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
  2022-07-13 14:24   ` Zach O'Keefe
@ 2022-07-13 19:04     ` Yang Shi
  0 siblings, 0 replies; 5+ messages in thread
From: Yang Shi @ 2022-07-13 19:04 UTC (permalink / raw)
  To: Zach O'Keefe
  Cc: Dan Carpenter, kbuild, kernel test robot, kbuild-all,
	Linux Kernel Mailing List, Andrew Morton,
	Linux Memory Management List

On Wed, Jul 13, 2022 at 7:24 AM Zach O'Keefe <zokeefe@google.com> wrote:
>
> On Jul 12 10:02, Yang Shi wrote:
> > On Tue, Jul 12, 2022 at 5:36 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> > >
> > > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
> > > head:   0e9f775fb0b4adf1a4ef50ea156ead09a0fc5194
> > > commit: 9f626ffb1d1c5c26b4a8e0fdffec784a5f773274 [284/293] mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse
> > > config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220710/202207100715.TBIYQ4fc-lkp@intel.com/config)
> > > compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
> > >
> > > If you fix the issue, kindly add following tag where applicable
> > > Reported-by: kernel test robot <lkp@intel.com>
> > > Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> > >
> > > smatch warnings:
> > > mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc'
> > >
> > > vim +/cc +2409 mm/khugepaged.c
> > >
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2387  int madvise_collapse(struct vm_area_struct *vma, struct vm_area_struct **prev,
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2388                 unsigned long start, unsigned long end)
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2389  {
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2390    struct collapse_control *cc;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2391    struct mm_struct *mm = vma->vm_mm;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2392    unsigned long hstart, hend, addr;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2393    int thps = 0, last_fail = SCAN_FAIL;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2394    bool mmap_locked = true;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2395
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2396    BUG_ON(vma->vm_start > start);
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2397    BUG_ON(vma->vm_end < end);
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2398
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2399    cc = kmalloc(sizeof(*cc), GFP_KERNEL);
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2400    if (!cc)
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2401            return -ENOMEM;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2402    cc->is_khugepaged = false;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2403    cc->last_target_node = NUMA_NO_NODE;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2404
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2405    *prev = vma;
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2406
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2407    /* TODO: Support file/shmem */
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06  2408    if (!vma->anon_vma || !vma_is_anonymous(vma))
> > > 9f626ffb1d1c5c Zach O'Keefe 2022-07-06 @2409            return -EINVAL;
> >
> > It seems better to move the cc kmalloc after the anonymous vma check?
> >
>
> Agreed - something I only noticed when fixing this. I've cleaned up some
> ordering here, now looks like:
>
> ---8<---
>         BUG_ON(vma->vm_start > start);
>         BUG_ON(vma->vm_end < end);
>
>         *prev = vma;
>
>         /* TODO: Support file/shmem */
>         if (!vma->anon_vma || !vma_is_anonymous(vma))
>                 return -EINVAL;
>
>         if (!hugepage_vma_check(vma, vma->vm_flags, false, false, false))
>                 return -EINVAL;
>
>         cc = kmalloc(sizeof(*cc), GFP_KERNEL);
>         if (!cc)
>                 return -ENOMEM;
>         cc->is_khugepaged = false;
>         cc->last_target_node = NUMA_NO_NODE;
>
>         mmgrab(mm);
>         lru_add_drain_all();
>
>         hstart = (start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
>         hend = end & HPAGE_PMD_MASK;
>
>         for (addr = hstart; addr < hend; addr += HPAGE_PMD_SIZE) {
> ---8<---
> out_nolock:
>         mmap_assert_locked(mm);
>         mmdrop(mm);
>         kfree(cc);
> ---8<---

Looks good to me.

>
> > >
> > > kfree(cc);?
> > >
> > >
> > > --
> > > 0-DAY CI Kernel Test Service
> > > https://01.org/lkp
> > >
> > >


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2022-07-13 19:04 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-12 12:35 [akpm-mm:mm-unstable 284/293] mm/khugepaged.c:2409 madvise_collapse() warn: possible memory leak of 'cc' Dan Carpenter
2022-07-12 13:46 ` Zach O'Keefe
2022-07-12 17:02 ` Yang Shi
2022-07-13 14:24   ` Zach O'Keefe
2022-07-13 19:04     ` Yang Shi

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