From: Chris Wilson chris@chris-wilson.co.uk

[ Upstream commit 119c53d2d4044c59c450c4f5a568d80b9d861856 ]

drm_gem_dumb_map_offset() now exists and does everything vgem_gem_dump_map does and *ought* to do.

In particular, vgem_gem_dumb_map() was trying to reject mmapping an imported dmabuf by checking the existence of obj->filp. Unfortunately, we always allocated an obj->filp, even if unused for an imported dmabuf. Instead, the drm_gem_dumb_map_offset(), since commit 90378e589192 ("drm/gem: drm_gem_dumb_map_offset(): reject dma-buf"), uses the obj->import_attach to reject such invalid mmaps.

This prevents vgem from allowing userspace mmapping the dumb handle and attempting to incorrectly fault in remote pages belonging to another device, where there may not even be a struct page.

v2: Use the default drm_gem_dumb_map_offset() callback

Fixes: af33a9190d02 ("drm/vgem: Enable dmabuf import interfaces") Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch Cc: stable@vger.kernel.org # v4.13+ Link: https://patchwork.freedesktop.org/patch/msgid/20200708154911.21236-1-chris@c... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/vgem/vgem_drv.c | 27 --------------------------- 1 file changed, 27 deletions(-)

diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index aa592277d5108..67037eb9a80ee 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -220,32 +220,6 @@ static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev, return 0; }

-static int vgem_gem_dumb_map(struct drm_file *file, struct drm_device *dev, - uint32_t handle, uint64_t *offset) -{ - struct drm_gem_object *obj; - int ret; - - obj = drm_gem_object_lookup(file, handle); - if (!obj) - return -ENOENT; - - if (!obj->filp) { - ret = -EINVAL; - goto unref; - } - - ret = drm_gem_create_mmap_offset(obj); - if (ret) - goto unref; - - *offset = drm_vma_node_offset_addr(&obj->vma_node); -unref: - drm_gem_object_put_unlocked(obj); - - return ret; -} - static struct drm_ioctl_desc vgem_ioctls[] = { DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_AUTH|DRM_RENDER_ALLOW), DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_AUTH|DRM_RENDER_ALLOW), @@ -439,7 +413,6 @@ static struct drm_driver vgem_driver = { .fops = &vgem_driver_fops,

.dumb_create = vgem_gem_dumb_create, - .dumb_map_offset = vgem_gem_dumb_map,

.prime_handle_to_fd = drm_gem_prime_handle_to_fd, .prime_fd_to_handle = drm_gem_prime_fd_to_handle,

From: Hugh Dickins hughd@google.com

[ Upstream commit bbe98f9cadff58cdd6a4acaeba0efa8565dabe65 ]

Move collapse_huge_page()'s mmget_still_valid() check into khugepaged_test_exit() itself. collapse_huge_page() is used for anon THP only, and earned its mmget_still_valid() check because it inserts a huge pmd entry in place of the page table's pmd entry; whereas collapse_file()'s retract_page_tables() or collapse_pte_mapped_thp() merely clears the page table's pmd entry. But core dumping without mmap lock must have been as open to mistaking a racily cleared pmd entry for a page table at physical page 0, as exit_mmap() was. And we certainly have no interest in mapping as a THP once dumping core.

Fixes: 59ea6d06cfa9 ("coredump: fix race condition between collapse_huge_page() and core dumping") Signed-off-by: Hugh Dickins hughd@google.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Cc: Andrea Arcangeli aarcange@redhat.com Cc: Song Liu songliubraving@fb.com Cc: Mike Kravetz mike.kravetz@oracle.com Cc: Kirill A. Shutemov kirill.shutemov@linux.intel.com Cc: stable@vger.kernel.org [4.8+] Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008021217020.27773@eggly.anvils Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- mm/khugepaged.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 04b4c38d0c184..a1b7475c05d04 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -394,7 +394,7 @@ static void insert_to_mm_slots_hash(struct mm_struct *mm,

static inline int khugepaged_test_exit(struct mm_struct *mm) { - return atomic_read(&mm->mm_users) == 0; + return atomic_read(&mm->mm_users) == 0 || !mmget_still_valid(mm); }

int __khugepaged_enter(struct mm_struct *mm) @@ -1006,9 +1006,6 @@ static void collapse_huge_page(struct mm_struct *mm, * handled by the anon_vma lock + PG_lock. */ down_write(&mm->mmap_sem); - result = SCAN_ANY_PROCESS; - if (!mmget_still_valid(mm)) - goto out; result = hugepage_vma_revalidate(mm, address, &vma); if (result) goto out;

From: Christophe Leroy christophe.leroy@c-s.fr

[ Upstream commit 0e36b0d12501e278686634712975b785bae11641 ]

Commit a7a9dcd882a67 ("powerpc: Avoid taking a data miss on every userspace instruction miss") has shown that limiting the read of faulting instruction to likely cases improves performance.

This patch goes further into this direction by limiting the read of the faulting instruction to the only cases where it is likely needed.

On an MPC885, with the same benchmark app as in the commit referred above, we see a reduction of about 3900 dTLB misses (approx 3%):

Before the patch: Performance counter stats for './fault 500' (10 runs):

683033312 cpu-cycles ( +- 0.03% ) 134538 dTLB-load-misses ( +- 0.03% ) 46099 iTLB-load-misses ( +- 0.02% ) 19681 faults ( +- 0.02% )

5.389747878 seconds time elapsed ( +- 0.06% )

With the patch:

Performance counter stats for './fault 500' (10 runs):

682112862 cpu-cycles ( +- 0.03% ) 130619 dTLB-load-misses ( +- 0.03% ) 46073 iTLB-load-misses ( +- 0.05% ) 19681 faults ( +- 0.01% )

5.381342641 seconds time elapsed ( +- 0.07% )

The proper work of the huge stack expansion was tested with the following app:

int main(int argc, char **argv) { char buf[1024 * 1025];

sprintf(buf, "Hello world !\n"); printf(buf);

exit(0); }

Signed-off-by: Christophe Leroy christophe.leroy@c-s.fr Reviewed-by: Nicholas Piggin npiggin@gmail.com [mpe: Add include of pagemap.h to fix build errors] Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/mm/fault.c | 50 ++++++++++++++++++++++++++++------------- 1 file changed, 34 insertions(+), 16 deletions(-)

diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 5fc8a010fdf07..998c77e600a43 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -22,6 +22,7 @@ #include <linux/errno.h> #include <linux/string.h> #include <linux/types.h> +#include <linux/pagemap.h> #include <linux/ptrace.h> #include <linux/mman.h> #include <linux/mm.h> @@ -66,15 +67,11 @@ static inline bool notify_page_fault(struct pt_regs *regs) }

/* - * Check whether the instruction at regs->nip is a store using + * Check whether the instruction inst is a store using * an update addressing form which will update r1. */ -static bool store_updates_sp(struct pt_regs *regs) +static bool store_updates_sp(unsigned int inst) { - unsigned int inst; - - if (get_user(inst, (unsigned int __user *)regs->nip)) - return false; /* check for 1 in the rA field */ if (((inst >> 16) & 0x1f) != 1) return false; @@ -228,8 +225,8 @@ static bool bad_kernel_fault(bool is_exec, unsigned long error_code, }

static bool bad_stack_expansion(struct pt_regs *regs, unsigned long address, - struct vm_area_struct *vma, - bool store_update_sp) + struct vm_area_struct *vma, unsigned int flags, + bool *must_retry) { /* * N.B. The POWER/Open ABI allows programs to access up to @@ -241,6 +238,7 @@ static bool bad_stack_expansion(struct pt_regs *regs, unsigned long address, * expand to 1MB without further checks. */ if (address + 0x100000 < vma->vm_end) { + unsigned int __user *nip = (unsigned int __user *)regs->nip; /* get user regs even if this fault is in kernel mode */ struct pt_regs *uregs = current->thread.regs; if (uregs == NULL) @@ -258,8 +256,22 @@ static bool bad_stack_expansion(struct pt_regs *regs, unsigned long address, * between the last mapped region and the stack will * expand the stack rather than segfaulting. */ - if (address + 2048 < uregs->gpr[1] && !store_update_sp) - return true; + if (address + 2048 >= uregs->gpr[1]) + return false; + + if ((flags & FAULT_FLAG_WRITE) && (flags & FAULT_FLAG_USER) && + access_ok(VERIFY_READ, nip, sizeof(*nip))) { + unsigned int inst; + int res; + + pagefault_disable(); + res = __get_user_inatomic(inst, nip); + pagefault_enable(); + if (!res) + return !store_updates_sp(inst); + *must_retry = true; + } + return true; } return false; } @@ -392,7 +404,7 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, int is_user = user_mode(regs); int is_write = page_fault_is_write(error_code); int fault, major = 0; - bool store_update_sp = false; + bool must_retry = false;

if (notify_page_fault(regs)) return 0; @@ -439,9 +451,6 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, * can result in fault, which will cause a deadlock when called with * mmap_sem held */ - if (is_write && is_user) - store_update_sp = store_updates_sp(regs); - if (is_user) flags |= FAULT_FLAG_USER; if (is_write) @@ -488,8 +497,17 @@ retry: return bad_area(regs, address);

/* The stack is being expanded, check if it's valid */ - if (unlikely(bad_stack_expansion(regs, address, vma, store_update_sp))) - return bad_area(regs, address); + if (unlikely(bad_stack_expansion(regs, address, vma, flags, + &must_retry))) { + if (!must_retry) + return bad_area(regs, address); + + up_read(&mm->mmap_sem); + if (fault_in_pages_readable((const char __user *)regs->nip, + sizeof(unsigned int))) + return bad_area_nosemaphore(regs, address); + goto retry; + }

/* Try to expand it */ if (unlikely(expand_stack(vma, address)))

From: Marcos Paulo de Souza mpdesouza@suse.com

[ Upstream commit c0c907a47dccf2cf26251a8fb4a8e7a3bf79ce84 ]

The functions will be used outside of export.c and super.c to allow resolving subvolume name from a given id, eg. for subvolume deletion by id ioctl.

Signed-off-by: Marcos Paulo de Souza mpdesouza@suse.com Reviewed-by: David Sterba dsterba@suse.com [ split from the next patch ] Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/ctree.h | 2 ++ fs/btrfs/export.c | 8 ++++---- fs/btrfs/export.h | 5 +++++ fs/btrfs/super.c | 8 ++++---- 4 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 5412b12491cb8..de951987fd23d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3262,6 +3262,8 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size); int btrfs_parse_options(struct btrfs_fs_info *info, char *options, unsigned long new_flags); int btrfs_sync_fs(struct super_block *sb, int wait); +char *btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, + u64 subvol_objectid);

static inline __printf(2, 3) void btrfs_no_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...) diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c index 3aeb5770f8965..b6ce765aa7f33 100644 --- a/fs/btrfs/export.c +++ b/fs/btrfs/export.c @@ -56,9 +56,9 @@ static int btrfs_encode_fh(struct inode *inode, u32 *fh, int *max_len, return type; }

-static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid, - u64 root_objectid, u32 generation, - int check_generation) +struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid, + u64 root_objectid, u32 generation, + int check_generation) { struct btrfs_fs_info *fs_info = btrfs_sb(sb); struct btrfs_root *root; @@ -151,7 +151,7 @@ static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh, return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1); }

-static struct dentry *btrfs_get_parent(struct dentry *child) +struct dentry *btrfs_get_parent(struct dentry *child) { struct inode *dir = d_inode(child); struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); diff --git a/fs/btrfs/export.h b/fs/btrfs/export.h index 91b3908e7c549..15db024621414 100644 --- a/fs/btrfs/export.h +++ b/fs/btrfs/export.h @@ -17,4 +17,9 @@ struct btrfs_fid { u64 parent_root_objectid; } __attribute__ ((packed));

+struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid, + u64 root_objectid, u32 generation, + int check_generation); +struct dentry *btrfs_get_parent(struct dentry *child); + #endif diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 17a8463ef35c1..ca95e57b60ee1 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -939,8 +939,8 @@ out: return error; }

-static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, - u64 subvol_objectid) +char *btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, + u64 subvol_objectid) { struct btrfs_root *root = fs_info->tree_root; struct btrfs_root *fs_root; @@ -1427,8 +1427,8 @@ static struct dentry *mount_subvol(const char *subvol_name, u64 subvol_objectid, goto out; } } - subvol_name = get_subvol_name_from_objectid(btrfs_sb(mnt->mnt_sb), - subvol_objectid); + subvol_name = btrfs_get_subvol_name_from_objectid( + btrfs_sb(mnt->mnt_sb), subvol_objectid); if (IS_ERR(subvol_name)) { root = ERR_CAST(subvol_name); subvol_name = NULL;

From: Nikolay Borisov nborisov@suse.com

[ Upstream commit cecc8d9038d164eda61fbcd72520975a554ea63e ]

This label is only executed if compress_file_range fails to create an inline extent. So move its code in the semantically related inline extent handling branch. No functional changes.

Signed-off-by: Nikolay Borisov nborisov@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/inode.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 57908ee964a20..dc520749f51db 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -629,7 +629,14 @@ cont: btrfs_free_reserved_data_space_noquota(inode, start, end - start + 1); - goto free_pages_out; + + for (i = 0; i < nr_pages; i++) { + WARN_ON(pages[i]->mapping); + put_page(pages[i]); + } + kfree(pages); + + return; } }

@@ -708,13 +715,6 @@ cleanup_and_bail_uncompressed: *num_added += 1;

return; - -free_pages_out: - for (i = 0; i < nr_pages; i++) { - WARN_ON(pages[i]->mapping); - put_page(pages[i]); - } - kfree(pages); }

static void free_async_extent_pages(struct async_extent *async_extent)

From: Josef Bacik josef@toxicpanda.com

Dave hit this splat during testing btrfs/078:

====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc6-default+ #1191 Not tainted ------------------------------------------------------ kswapd0/75 is trying to acquire lock: ffffa040e9d04ff8 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs]

but task is already holding lock: ffffffff8b0c8040 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (fs_reclaim){+.+.}-{0:0}: __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 fs_reclaim_acquire.part.0+0x25/0x30 __kmalloc_track_caller+0x49/0x330 kstrdup+0x2e/0x60 __kernfs_new_node.constprop.0+0x44/0x250 kernfs_new_node+0x25/0x50 kernfs_create_link+0x34/0xa0 sysfs_do_create_link_sd+0x5e/0xd0 btrfs_sysfs_add_devices_dir+0x65/0x100 [btrfs] btrfs_init_new_device+0x44c/0x12b0 [btrfs] btrfs_ioctl+0xc3c/0x25c0 [btrfs] ksys_ioctl+0x68/0xa0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0xe0 entry_SYSCALL_64_after_hwframe+0x44/0xa9

-> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 __mutex_lock+0xa0/0xaf0 btrfs_chunk_alloc+0x137/0x3e0 [btrfs] find_free_extent+0xb44/0xfb0 [btrfs] btrfs_reserve_extent+0x9b/0x180 [btrfs] btrfs_alloc_tree_block+0xc1/0x350 [btrfs] alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs] __btrfs_cow_block+0x143/0x7a0 [btrfs] btrfs_cow_block+0x15f/0x310 [btrfs] push_leaf_right+0x150/0x240 [btrfs] split_leaf+0x3cd/0x6d0 [btrfs] btrfs_search_slot+0xd14/0xf70 [btrfs] btrfs_insert_empty_items+0x64/0xc0 [btrfs] __btrfs_commit_inode_delayed_items+0xb2/0x840 [btrfs] btrfs_async_run_delayed_root+0x10e/0x1d0 [btrfs] btrfs_work_helper+0x2f9/0x650 [btrfs] process_one_work+0x22c/0x600 worker_thread+0x50/0x3b0 kthread+0x137/0x150 ret_from_fork+0x1f/0x30

-> #0 (&delayed_node->mutex){+.+.}-{3:3}: check_prev_add+0x98/0xa20 validate_chain+0xa8c/0x2a00 __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 __mutex_lock+0xa0/0xaf0 __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] btrfs_evict_inode+0x3bf/0x560 [btrfs] evict+0xd6/0x1c0 dispose_list+0x48/0x70 prune_icache_sb+0x54/0x80 super_cache_scan+0x121/0x1a0 do_shrink_slab+0x175/0x420 shrink_slab+0xb1/0x2e0 shrink_node+0x192/0x600 balance_pgdat+0x31f/0x750 kswapd+0x206/0x510 kthread+0x137/0x150 ret_from_fork+0x1f/0x30

other info that might help us debug this:

Chain exists of: &delayed_node->mutex --> &fs_info->chunk_mutex --> fs_reclaim

Possible unsafe locking scenario:

CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&fs_info->chunk_mutex); lock(fs_reclaim); lock(&delayed_node->mutex);

*** DEADLOCK ***

3 locks held by kswapd0/75: #0: ffffffff8b0c8040 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 #1: ffffffff8b0b50b8 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x54/0x2e0 #2: ffffa040e057c0e8 (&type->s_umount_key#26){++++}-{3:3}, at: trylock_super+0x16/0x50

stack backtrace: CPU: 2 PID: 75 Comm: kswapd0 Not tainted 5.8.0-rc6-default+ #1191 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x16f/0x190 check_prev_add+0x98/0xa20 validate_chain+0xa8c/0x2a00 __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] __mutex_lock+0xa0/0xaf0 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] ? __lock_acquire+0x56f/0xaa0 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] ? lock_acquire+0xa3/0x440 ? btrfs_evict_inode+0x138/0x560 [btrfs] ? btrfs_evict_inode+0x2fe/0x560 [btrfs] ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] btrfs_evict_inode+0x3bf/0x560 [btrfs] evict+0xd6/0x1c0 dispose_list+0x48/0x70 prune_icache_sb+0x54/0x80 super_cache_scan+0x121/0x1a0 do_shrink_slab+0x175/0x420 shrink_slab+0xb1/0x2e0 shrink_node+0x192/0x600 balance_pgdat+0x31f/0x750 kswapd+0x206/0x510 ? _raw_spin_unlock_irqrestore+0x3e/0x50 ? finish_wait+0x90/0x90 ? balance_pgdat+0x750/0x750 kthread+0x137/0x150 ? kthread_stop+0x2a0/0x2a0 ret_from_fork+0x1f/0x30

This is because we're holding the chunk_mutex while adding this device and adding its sysfs entries. We actually hold different locks in different places when calling this function, the dev_replace semaphore for instance in dev replace, so instead of moving this call around simply wrap it's operations in NOFS.

CC: stable@vger.kernel.org # 4.14+ Reported-by: David Sterba dsterba@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com --- fs/btrfs/sysfs.c | 4 ++++ 1 file changed, 4 insertions(+)

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index f05341bda1d14..383546ff62f04 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -25,6 +25,7 @@ #include <linux/bug.h> #include <linux/genhd.h> #include <linux/debugfs.h> +#include <linux/sched/mm.h>

#include "ctree.h" #include "disk-io.h" @@ -749,7 +750,9 @@ int btrfs_sysfs_add_device_link(struct btrfs_fs_devices *fs_devices, { int error = 0; struct btrfs_device *dev; + unsigned int nofs_flag;

+ nofs_flag = memalloc_nofs_save(); list_for_each_entry(dev, &fs_devices->devices, dev_list) { struct hd_struct *disk; struct kobject *disk_kobj; @@ -768,6 +771,7 @@ int btrfs_sysfs_add_device_link(struct btrfs_fs_devices *fs_devices, if (error) break; } + memalloc_nofs_restore(nofs_flag);

return error; }

From: Wei Yongjun weiyongjun1@huawei.com

commit 71e843295c680898959b22dc877ae3839cc22470 upstream.

kmemleak report memory leak as follows:

unreferenced object 0x607ee4e5f948 (size 8): comm "syz-executor.1", pid 2098, jiffies 4295031601 (age 288.468s) hex dump (first 8 bytes): 00 00 00 00 00 00 00 00 ........ backtrace: relay_open kernel/relay.c:583 [inline] relay_open+0xb6/0x970 kernel/relay.c:563 do_blk_trace_setup+0x4a8/0xb20 kernel/trace/blktrace.c:557 __blk_trace_setup+0xb6/0x150 kernel/trace/blktrace.c:597 blk_trace_ioctl+0x146/0x280 kernel/trace/blktrace.c:738 blkdev_ioctl+0xb2/0x6a0 block/ioctl.c:613 block_ioctl+0xe5/0x120 fs/block_dev.c:1871 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x170/0x1ce fs/ioctl.c:739 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9

'chan->buf' is malloced in relay_open() by alloc_percpu() but not free while destroy the relay channel. Fix it by adding free_percpu() before return from relay_destroy_channel().

Fixes: 017c59c042d0 ("relay: Use per CPU constructs for the relay channel buffer pointers") Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: Wei Yongjun weiyongjun1@huawei.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Reviewed-by: Chris Wilson chris@chris-wilson.co.uk Cc: Al Viro viro@zeniv.linux.org.uk Cc: Michael Ellerman mpe@ellerman.id.au Cc: David Rientjes rientjes@google.com Cc: Michel Lespinasse walken@google.com Cc: Daniel Axtens dja@axtens.net Cc: Thomas Gleixner tglx@linutronix.de Cc: Akash Goel akash.goel@intel.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20200817122826.48518-1-weiyongjun1@huawei.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- kernel/relay.c | 1 + 1 file changed, 1 insertion(+)

--- a/kernel/relay.c +++ b/kernel/relay.c @@ -196,6 +196,7 @@ free_buf: static void relay_destroy_channel(struct kref *kref) { struct rchan *chan = container_of(kref, struct rchan, kref); + free_percpu(chan->buf); kfree(chan); }

From: Charan Teja Reddy charante@codeaurora.org

commit 88e8ac11d2ea3acc003cf01bb5a38c8aa76c3cfd upstream.

The following race is observed with the repeated online, offline and a delay between two successive online of memory blocks of movable zone.

P1 P2

Online the first memory block in the movable zone. The pcp struct values are initialized to default values,i.e., pcp->high = 0 & pcp->batch = 1.

Allocate the pages from the movable zone.

Try to Online the second memory block in the movable zone thus it entered the online_pages() but yet to call zone_pcp_update(). This process is entered into the exit path thus it tries to release the order-0 pages to pcp lists through free_unref_page_commit(). As pcp->high = 0, pcp->count = 1 proceed to call the function free_pcppages_bulk(). Update the pcp values thus the new pcp values are like, say, pcp->high = 378, pcp->batch = 63. Read the pcp's batch value using READ_ONCE() and pass the same to free_pcppages_bulk(), pcp values passed here are, batch = 63, count = 1.

Since num of pages in the pcp lists are less than ->batch, then it will stuck in while(list_empty(list)) loop with interrupts disabled thus a core hung.

Avoid this by ensuring free_pcppages_bulk() is called with proper count of pcp list pages.

The mentioned race is some what easily reproducible without [1] because pcp's are not updated for the first memory block online and thus there is a enough race window for P2 between alloc+free and pcp struct values update through onlining of second memory block.

With [1], the race still exists but it is very narrow as we update the pcp struct values for the first memory block online itself.

This is not limited to the movable zone, it could also happen in cases with the normal zone (e.g., hotplug to a node that only has DMA memory, or no other memory yet).

[1]: https://patchwork.kernel.org/patch/11696389/

Fixes: 5f8dcc21211a ("page-allocator: split per-cpu list into one-list-per-migrate-type") Signed-off-by: Charan Teja Reddy charante@codeaurora.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Acked-by: David Hildenbrand david@redhat.com Acked-by: David Rientjes rientjes@google.com Acked-by: Michal Hocko mhocko@suse.com Cc: Michal Hocko mhocko@suse.com Cc: Vlastimil Babka vbabka@suse.cz Cc: Vinayak Menon vinmenon@codeaurora.org Cc: stable@vger.kernel.org [2.6+] Link: http://lkml.kernel.org/r/1597150703-19003-1-git-send-email-charante@codeauro... Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- mm/page_alloc.c | 5 +++++ 1 file changed, 5 insertions(+)

--- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1114,6 +1114,11 @@ static void free_pcppages_bulk(struct zo spin_lock(&zone->lock); isolated_pageblocks = has_isolate_pageblock(zone);

+ /* + * Ensure proper count is passed which otherwise would stuck in the + * below while (list_empty(list)) loop. + */ + count = min(pcp->count, count); while (count) { struct page *page; struct list_head *list;

From: zhangyi (F) yi.zhang@huawei.com

commit ef3f5830b859604eda8723c26d90ab23edc027a4 upstream.

jbd2_write_superblock() is under the buffer lock of journal superblock before ending that superblock write, so add a missing unlock_buffer() in in the error path before submitting buffer.

Fixes: 742b06b5628f ("jbd2: check superblock mapped prior to committing") Signed-off-by: zhangyi (F) yi.zhang@huawei.com Reviewed-by: Ritesh Harjani riteshh@linux.ibm.com Cc: stable@kernel.org Link: https://lore.kernel.org/r/20200620061948.2049579-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- fs/jbd2/journal.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1356,8 +1356,10 @@ static int jbd2_write_superblock(journal int ret;

/* Buffer got discarded which means block device got invalidated */ - if (!buffer_mapped(bh)) + if (!buffer_mapped(bh)) { + unlock_buffer(bh); return -EIO; + }

trace_jbd2_write_superblock(journal, write_flags); if (!(journal->j_flags & JBD2_BARRIER))

From: Lukas Wunner lukas@wunner.de

[ Upstream commit ddf75be47ca748f8b12d28ac64d624354fddf189 ]

CONFIG_OF_DYNAMIC and CONFIG_ACPI allow adding SPI devices at runtime using a DeviceTree overlay or DSDT patch. CONFIG_SPI_SLAVE allows the same via sysfs.

But there are no precautions to prevent adding a device below a controller that's being removed. Such a device is unusable and may not even be able to unbind cleanly as it becomes inaccessible once the controller has been torn down. E.g. it is then impossible to quiesce the device's interrupt.

of_spi_notify() and acpi_spi_notify() do hold a ref on the controller, but otherwise run lockless against spi_unregister_controller().

Fix by holding the spi_add_lock in spi_unregister_controller() and bailing out of spi_add_device() if the controller has been unregistered concurrently.

Fixes: ce79d54ae447 ("spi/of: Add OF notifier handler") Signed-off-by: Lukas Wunner lukas@wunner.de Cc: stable@vger.kernel.org # v3.19+ Cc: Geert Uytterhoeven geert+renesas@glider.be Cc: Octavian Purdila octavian.purdila@intel.com Cc: Pantelis Antoniou pantelis.antoniou@konsulko.com Link: https://lore.kernel.org/r/a8c3205088a969dc8410eec1eba9aface60f36af.159645103... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/Kconfig | 3 +++ drivers/spi/spi.c | 21 ++++++++++++++++++++- 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index a75f2a2cf7805..4b6a1629969f3 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -827,4 +827,7 @@ config SPI_SLAVE_SYSTEM_CONTROL

endif # SPI_SLAVE

+config SPI_DYNAMIC + def_bool ACPI || OF_DYNAMIC || SPI_SLAVE + endif # SPI diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 49eee894f51d4..ab6a4f85bcde7 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -428,6 +428,12 @@ static LIST_HEAD(spi_controller_list); */ static DEFINE_MUTEX(board_lock);

+/* + * Prevents addition of devices with same chip select and + * addition of devices below an unregistering controller. + */ +static DEFINE_MUTEX(spi_add_lock); + /** * spi_alloc_device - Allocate a new SPI device * @ctlr: Controller to which device is connected @@ -506,7 +512,6 @@ static int spi_dev_check(struct device *dev, void *data) */ int spi_add_device(struct spi_device *spi) { - static DEFINE_MUTEX(spi_add_lock); struct spi_controller *ctlr = spi->controller; struct device *dev = ctlr->dev.parent; int status; @@ -534,6 +539,13 @@ int spi_add_device(struct spi_device *spi) goto done; }

+ /* Controller may unregister concurrently */ + if (IS_ENABLED(CONFIG_SPI_DYNAMIC) && + !device_is_registered(&ctlr->dev)) { + status = -ENODEV; + goto done; + } + if (ctlr->cs_gpios) spi->cs_gpio = ctlr->cs_gpios[spi->chip_select];

@@ -2265,6 +2277,10 @@ void spi_unregister_controller(struct spi_controller *ctlr) struct spi_controller *found; int id = ctlr->bus_num;

+ /* Prevent addition of new devices, unregister existing ones */ + if (IS_ENABLED(CONFIG_SPI_DYNAMIC)) + mutex_lock(&spi_add_lock); + device_for_each_child(&ctlr->dev, NULL, __unregister);

/* First make sure that this controller was ever added */ @@ -2285,6 +2301,9 @@ void spi_unregister_controller(struct spi_controller *ctlr) if (found == ctlr) idr_remove(&spi_master_idr, id); mutex_unlock(&board_lock); + + if (IS_ENABLED(CONFIG_SPI_DYNAMIC)) + mutex_unlock(&spi_add_lock); } EXPORT_SYMBOL_GPL(spi_unregister_controller);

From: Chuhong Yuan hslester96@gmail.com

[ Upstream commit fc0456458df8b3421dba2a5508cd817fbc20ea71 ]

budget_register() has no error handling after its failure. Add the missed undo functions for error handling to fix it.

Signed-off-by: Chuhong Yuan hslester96@gmail.com Signed-off-by: Sean Young sean@mess.org Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/pci/ttpci/budget-core.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/media/pci/ttpci/budget-core.c b/drivers/media/pci/ttpci/budget-core.c index 97499b2af7144..20524376b83be 100644 --- a/drivers/media/pci/ttpci/budget-core.c +++ b/drivers/media/pci/ttpci/budget-core.c @@ -383,20 +383,25 @@ static int budget_register(struct budget *budget) ret = dvbdemux->dmx.add_frontend(&dvbdemux->dmx, &budget->hw_frontend);

if (ret < 0) - return ret; + goto err_release_dmx;

budget->mem_frontend.source = DMX_MEMORY_FE; ret = dvbdemux->dmx.add_frontend(&dvbdemux->dmx, &budget->mem_frontend); if (ret < 0) - return ret; + goto err_release_dmx;

ret = dvbdemux->dmx.connect_frontend(&dvbdemux->dmx, &budget->hw_frontend); if (ret < 0) - return ret; + goto err_release_dmx;

dvb_net_init(&budget->dvb_adapter, &budget->dvb_net, &dvbdemux->dmx);

return 0; + +err_release_dmx: + dvb_dmxdev_release(&budget->dmxdev); + dvb_dmx_release(&budget->demux); + return ret; }

static void budget_unregister(struct budget *budget)

From: Evgeny Novikov novikov@ispras.ru

[ Upstream commit 9c487b0b0ea7ff22127fe99a7f67657d8730ff94 ]

If platform_driver_register() fails within vpss_init() resources are not cleaned up. The patch fixes this issue by introducing the corresponding error handling.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Evgeny Novikov novikov@ispras.ru Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/platform/davinci/vpss.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/media/platform/davinci/vpss.c b/drivers/media/platform/davinci/vpss.c index 2ee4cd9e6d80f..d984f45c03149 100644 --- a/drivers/media/platform/davinci/vpss.c +++ b/drivers/media/platform/davinci/vpss.c @@ -514,19 +514,31 @@ static void vpss_exit(void)

static int __init vpss_init(void) { + int ret; + if (!request_mem_region(VPSS_CLK_CTRL, 4, "vpss_clock_control")) return -EBUSY;

oper_cfg.vpss_regs_base2 = ioremap(VPSS_CLK_CTRL, 4); if (unlikely(!oper_cfg.vpss_regs_base2)) { - release_mem_region(VPSS_CLK_CTRL, 4); - return -ENOMEM; + ret = -ENOMEM; + goto err_ioremap; }

writel(VPSS_CLK_CTRL_VENCCLKEN | - VPSS_CLK_CTRL_DACCLKEN, oper_cfg.vpss_regs_base2); + VPSS_CLK_CTRL_DACCLKEN, oper_cfg.vpss_regs_base2); + + ret = platform_driver_register(&vpss_driver); + if (ret) + goto err_pd_register; + + return 0;

- return platform_driver_register(&vpss_driver); +err_pd_register: + iounmap(oper_cfg.vpss_regs_base2); +err_ioremap: + release_mem_region(VPSS_CLK_CTRL, 4); + return ret; } subsys_initcall(vpss_init); module_exit(vpss_exit);

From: Greg Ungerer gerg@linux-m68k.org

[ Upstream commit bdee0e793cea10c516ff48bf3ebb4ef1820a116b ]

The Cache Control Register (CACR) of the ColdFire V3 has bits that control high level caching functions, and also enable/disable the use of the alternate stack pointer register (the EUSP bit) to provide separate supervisor and user stack pointer registers. The code as it is today will blindly clear the EUSP bit on cache actions like invalidation. So it is broken for this case - and that will result in failed booting (interrupt entry and exit processing will be completely hosed).

This only affects ColdFire V3 parts that support the alternate stack register (like the 5329 for example) - generally speaking new parts do, older parts don't. It has no impact on ColdFire V3 parts with the single stack pointer, like the 5307 for example.

Fix the cache bit defines used, so they maintain the EUSP bit when carrying out cache actions through the CACR register.

Signed-off-by: Greg Ungerer gerg@linux-m68k.org Signed-off-by: Sasha Levin sashal@kernel.org --- arch/m68k/include/asm/m53xxacr.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/m68k/include/asm/m53xxacr.h b/arch/m68k/include/asm/m53xxacr.h index 9138a624c5c81..692f90e7fecc1 100644 --- a/arch/m68k/include/asm/m53xxacr.h +++ b/arch/m68k/include/asm/m53xxacr.h @@ -89,9 +89,9 @@ * coherency though in all cases. And for copyback caches we will need * to push cached data as well. */ -#define CACHE_INIT CACR_CINVA -#define CACHE_INVALIDATE CACR_CINVA -#define CACHE_INVALIDATED CACR_CINVA +#define CACHE_INIT (CACHE_MODE + CACR_CINVA - CACR_EC) +#define CACHE_INVALIDATE (CACHE_MODE + CACR_CINVA) +#define CACHE_INVALIDATED (CACHE_MODE + CACR_CINVA)

#define ACR0_MODE ((CONFIG_RAMBASE & 0xff000000) + \ (0x000f0000) + \

From: Zhe Li lizhe67@huawei.com

[ Upstream commit 798b7347e4f29553db4b996393caf12f5b233daf ]

The log of UAF problem is listed below. BUG: KASAN: use-after-free in jffs2_rmdir+0xa4/0x1cc [jffs2] at addr c1f165fc Read of size 4 by task rm/8283 ============================================================================= BUG kmalloc-32 (Tainted: P B O ): kasan: bad access detected -----------------------------------------------------------------------------

INFO: Allocated in 0xbbbbbbbb age=3054364 cpu=0 pid=0 0xb0bba6ef jffs2_write_dirent+0x11c/0x9c8 [jffs2] __slab_alloc.isra.21.constprop.25+0x2c/0x44 __kmalloc+0x1dc/0x370 jffs2_write_dirent+0x11c/0x9c8 [jffs2] jffs2_do_unlink+0x328/0x5fc [jffs2] jffs2_rmdir+0x110/0x1cc [jffs2] vfs_rmdir+0x180/0x268 do_rmdir+0x2cc/0x300 ret_from_syscall+0x0/0x3c INFO: Freed in 0x205b age=3054364 cpu=0 pid=0 0x2e9173 jffs2_add_fd_to_list+0x138/0x1dc [jffs2] jffs2_add_fd_to_list+0x138/0x1dc [jffs2] jffs2_garbage_collect_dirent.isra.3+0x21c/0x288 [jffs2] jffs2_garbage_collect_live+0x16bc/0x1800 [jffs2] jffs2_garbage_collect_pass+0x678/0x11d4 [jffs2] jffs2_garbage_collect_thread+0x1e8/0x3b0 [jffs2] kthread+0x1a8/0x1b0 ret_from_kernel_thread+0x5c/0x64 Call Trace: [c17ddd20] [c02452d4] kasan_report.part.0+0x298/0x72c (unreliable) [c17ddda0] [d2509680] jffs2_rmdir+0xa4/0x1cc [jffs2] [c17dddd0] [c026da04] vfs_rmdir+0x180/0x268 [c17dde00] [c026f4e4] do_rmdir+0x2cc/0x300 [c17ddf40] [c001a658] ret_from_syscall+0x0/0x3c

The root cause is that we don't get "jffs2_inode_info.sem" before we scan list "jffs2_inode_info.dents" in function jffs2_rmdir. This patch add codes to get "jffs2_inode_info.sem" before we scan "jffs2_inode_info.dents" to slove the UAF problem.

Signed-off-by: Zhe Li lizhe67@huawei.com Reviewed-by: Hou Tao houtao1@huawei.com Signed-off-by: Richard Weinberger richard@nod.at Signed-off-by: Sasha Levin sashal@kernel.org --- fs/jffs2/dir.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c index e5a6deb38e1e1..f4a5ec92f5dc7 100644 --- a/fs/jffs2/dir.c +++ b/fs/jffs2/dir.c @@ -590,10 +590,14 @@ static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry) int ret; uint32_t now = get_seconds();

+ mutex_lock(&f->sem); for (fd = f->dents ; fd; fd = fd->next) { - if (fd->ino) + if (fd->ino) { + mutex_unlock(&f->sem); return -ENOTEMPTY; + } } + mutex_unlock(&f->sem);

ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name, dentry->d_name.len, f, now);

From: Javed Hasan jhasan@marvell.com

[ Upstream commit ec007ef40abb6a164d148b0dc19789a7a2de2cc8 ]

In fc_disc_gpn_id_resp(), skb is supposed to get freed in all cases except for PTR_ERR. However, in some cases it didn't.

This fix is to call fc_frame_free(fp) before function returns.

Link: https://lore.kernel.org/r/20200729081824.30996-2-jhasan@marvell.com Reviewed-by: Girish Basrur gbasrur@marvell.com Reviewed-by: Santosh Vernekar svernekar@marvell.com Reviewed-by: Saurav Kashyap skashyap@marvell.com Reviewed-by: Shyam Sundar ssundar@marvell.com Signed-off-by: Javed Hasan jhasan@marvell.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/libfc/fc_disc.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/libfc/fc_disc.c b/drivers/scsi/libfc/fc_disc.c index 28b50ab2fbb01..62f83cc151b22 100644 --- a/drivers/scsi/libfc/fc_disc.c +++ b/drivers/scsi/libfc/fc_disc.c @@ -605,8 +605,12 @@ static void fc_disc_gpn_id_resp(struct fc_seq *sp, struct fc_frame *fp,

if (PTR_ERR(fp) == -FC_EX_CLOSED) goto out; - if (IS_ERR(fp)) - goto redisc; + if (IS_ERR(fp)) { + mutex_lock(&disc->disc_mutex); + fc_disc_restart(disc); + mutex_unlock(&disc->disc_mutex); + goto out; + }

cp = fc_frame_payload_get(fp, sizeof(*cp)); if (!cp) @@ -633,7 +637,7 @@ static void fc_disc_gpn_id_resp(struct fc_seq *sp, struct fc_frame *fp, new_rdata->disc_id = disc->disc_id; fc_rport_login(new_rdata); } - goto out; + goto free_fp; } rdata->disc_id = disc->disc_id; mutex_unlock(&rdata->rp_mutex); @@ -650,6 +654,8 @@ redisc: fc_disc_restart(disc); mutex_unlock(&disc->disc_mutex); } +free_fp: + fc_frame_free(fp); out: kref_put(&rdata->kref, fc_rport_destroy); if (!IS_ERR(fp))

From: Eiichi Tsukata devel@etsukata.com

[ Upstream commit 96cf2a2c75567ff56195fe3126d497a2e7e4379f ]

If xfs_sysfs_init is called with parent_kobj == NULL, UBSAN shows the following warning:

UBSAN: null-ptr-deref in ./fs/xfs/xfs_sysfs.h:37:23 member access within null pointer of type 'struct xfs_kobj' Call Trace: dump_stack+0x10e/0x195 ubsan_type_mismatch_common+0x241/0x280 __ubsan_handle_type_mismatch_v1+0x32/0x40 init_xfs_fs+0x12b/0x28f do_one_initcall+0xdd/0x1d0 do_initcall_level+0x151/0x1b6 do_initcalls+0x50/0x8f do_basic_setup+0x29/0x2b kernel_init_freeable+0x19f/0x20b kernel_init+0x11/0x1e0 ret_from_fork+0x22/0x30

Fix it by checking parent_kobj before the code accesses its member.

Signed-off-by: Eiichi Tsukata devel@etsukata.com Reviewed-by: Darrick J. Wong darrick.wong@oracle.com [darrick: minor whitespace edits] Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/xfs/xfs_sysfs.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_sysfs.h b/fs/xfs/xfs_sysfs.h index d04637181ef21..980c9429abec5 100644 --- a/fs/xfs/xfs_sysfs.h +++ b/fs/xfs/xfs_sysfs.h @@ -44,9 +44,11 @@ xfs_sysfs_init( struct xfs_kobj *parent_kobj, const char *name) { + struct kobject *parent; + + parent = parent_kobj ? &parent_kobj->kobject : NULL; init_completion(&kobj->complete); - return kobject_init_and_add(&kobj->kobject, ktype, - &parent_kobj->kobject, "%s", name); + return kobject_init_and_add(&kobj->kobject, ktype, parent, "%s", name); }

static inline void

From: Eric Sandeen sandeen@redhat.com

[ Upstream commit 5872331b3d91820e14716632ebb56b1399b34fe1 ]

If for any reason a directory passed to do_split() does not have enough active entries to exceed half the size of the block, we can end up iterating over all "count" entries without finding a split point.

In this case, count == move, and split will be zero, and we will attempt a negative index into map[].

Guard against this by detecting this case, and falling back to split-to-half-of-count instead; in this case we will still have plenty of space (> half blocksize) in each split block.

Fixes: ef2b02d3e617 ("ext34: ensure do_split leaves enough free space in both blocks") Signed-off-by: Eric Sandeen sandeen@redhat.com Reviewed-by: Andreas Dilger adilger@dilger.ca Reviewed-by: Jan Kara jack@suse.cz Link: https://lore.kernel.org/r/f53e246b-647c-64bb-16ec-135383c70ad7@redhat.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ext4/namei.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index ed17edb31e22f..3f999053457b6 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1741,7 +1741,7 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, blocksize, hinfo, map); map -= count; dx_sort_map(map, count); - /* Split the existing block in the middle, size-wise */ + /* Ensure that neither split block is over half full */ size = 0; move = 0; for (i = count-1; i >= 0; i--) { @@ -1751,8 +1751,18 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, size += map[i].size; move++; } - /* map index at which we will split */ - split = count - move; + /* + * map index at which we will split + * + * If the sum of active entries didn't exceed half the block size, just + * split it in half by count; each resulting block will have at least + * half the space free. + */ + if (i > 0) + split = count - move; + else + split = count/2; + hash2 = map[split].hash; continued = hash2 == map[split - 1].hash; dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",

From: Grzegorz Szczurek grzegorzx.szczurek@intel.com

[ Upstream commit 5b6d4a7f20b09c47ca598760f6dafd554af8b6d5 ]

Fix the reason of crashing system by add waiting time to finish reset recovery process before starting remove driver procedure. Now VSI is releasing if VSI is not in reset recovery mode. Without this fix it was possible to start remove driver if other processing command need reset recovery procedure which resulted in null pointer dereference. VSI used by the ethtool process has been cleared by remove driver process.

[ 6731.508665] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 6731.508668] #PF: supervisor read access in kernel mode [ 6731.508670] #PF: error_code(0x0000) - not-present page [ 6731.508671] PGD 0 P4D 0 [ 6731.508674] Oops: 0000 [#1] SMP PTI [ 6731.508679] Hardware name: Intel Corporation S2600WT2R/S2600WT2R, BIOS SE5C610.86B.01.01.0021.032120170601 03/21/2017 [ 6731.508694] RIP: 0010:i40e_down+0x252/0x310 [i40e] [ 6731.508696] Code: c7 78 de fa c0 e8 61 02 3a c1 66 83 bb f6 0c 00 00 00 0f 84 bf 00 00 00 45 31 e4 45 31 ff eb 03 41 89 c7 48 8b 83 98 0c 00 00 <4a> 8b 3c 20 e8 a5 79 02 00 48 83 bb d0 0c 00 00 00 74 10 48 8b 83 [ 6731.508698] RSP: 0018:ffffb75ac7b3faf0 EFLAGS: 00010246 [ 6731.508700] RAX: 0000000000000000 RBX: ffff9c9874bd5000 RCX: 0000000000000007 [ 6731.508701] RDX: 0000000000000000 RSI: 0000000000000096 RDI: ffff9c987f4d9780 [ 6731.508703] RBP: ffffb75ac7b3fb30 R08: 0000000000005b60 R09: 0000000000000004 [ 6731.508704] R10: ffffb75ac64fbd90 R11: 0000000000000001 R12: 0000000000000000 [ 6731.508706] R13: ffff9c97a08e0000 R14: ffff9c97a08e0a68 R15: 0000000000000000 [ 6731.508708] FS: 00007f2617cd2740(0000) GS:ffff9c987f4c0000(0000) knlGS:0000000000000000 [ 6731.508710] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6731.508711] CR2: 0000000000000000 CR3: 0000001e765c4006 CR4: 00000000003606e0 [ 6731.508713] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 6731.508714] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 6731.508715] Call Trace: [ 6731.508734] i40e_vsi_close+0x84/0x90 [i40e] [ 6731.508742] i40e_quiesce_vsi.part.98+0x3c/0x40 [i40e] [ 6731.508749] i40e_pf_quiesce_all_vsi+0x55/0x60 [i40e] [ 6731.508757] i40e_prep_for_reset+0x59/0x130 [i40e] [ 6731.508765] i40e_reconfig_rss_queues+0x5a/0x120 [i40e] [ 6731.508774] i40e_set_channels+0xda/0x170 [i40e] [ 6731.508778] ethtool_set_channels+0xe9/0x150 [ 6731.508781] dev_ethtool+0x1b94/0x2920 [ 6731.508805] dev_ioctl+0xc2/0x590 [ 6731.508811] sock_do_ioctl+0xae/0x150 [ 6731.508813] sock_ioctl+0x34f/0x3c0 [ 6731.508821] ksys_ioctl+0x98/0xb0 [ 6731.508828] __x64_sys_ioctl+0x1a/0x20 [ 6731.508831] do_syscall_64+0x57/0x1c0 [ 6731.508835] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 4b8164467b85 ("i40e: Add common function for finding VSI by type") Signed-off-by: Grzegorz Szczurek grzegorzx.szczurek@intel.com Signed-off-by: Arkadiusz Kubalewski arkadiusz.kubalewski@intel.com Tested-by: Aaron Brown aaron.f.brown@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/i40e/i40e_main.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index aa2b446d6ad0f..f4475cbf8ce86 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -11822,6 +11822,9 @@ static void i40e_remove(struct pci_dev *pdev) i40e_write_rx_ctl(hw, I40E_PFQF_HENA(0), 0); i40e_write_rx_ctl(hw, I40E_PFQF_HENA(1), 0);

+ while (test_bit(__I40E_RESET_RECOVERY_PENDING, pf->state)) + usleep_range(1000, 2000); + /* no more scheduling of any task */ set_bit(__I40E_SUSPENDED, pf->state); set_bit(__I40E_DOWN, pf->state);

From: Jarod Wilson jarod@redhat.com

[ Upstream commit 4ca0d9ac3fd8f9f90b72a15d8da2aca3ffb58418 ]

Broadcast mode bonds transmit a copy of all traffic simultaneously out of all interfaces, so the "speed" of the bond isn't really the aggregate of all interfaces, but rather, the speed of the slowest active interface.

Also, the type of the speed field is u32, not unsigned long, so adjust that accordingly, as required to make min() function here without complaining about mismatching types.

Fixes: bb5b052f751b ("bond: add support to read speed and duplex via ethtool") CC: Jay Vosburgh j.vosburgh@gmail.com CC: Veaceslav Falico vfalico@gmail.com CC: Andy Gospodarek andy@greyhouse.net CC: "David S. Miller" davem@davemloft.net CC: netdev@vger.kernel.org Acked-by: Jay Vosburgh jay.vosburgh@canonical.com Signed-off-by: Jarod Wilson jarod@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/bonding/bond_main.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 1f867e275408e..9ddbafdca3b05 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -4156,13 +4156,23 @@ static netdev_tx_t bond_start_xmit(struct sk_buff *skb, struct net_device *dev) return ret; }

+static u32 bond_mode_bcast_speed(struct slave *slave, u32 speed) +{ + if (speed == 0 || speed == SPEED_UNKNOWN) + speed = slave->speed; + else + speed = min(speed, slave->speed); + + return speed; +} + static int bond_ethtool_get_link_ksettings(struct net_device *bond_dev, struct ethtool_link_ksettings *cmd) { struct bonding *bond = netdev_priv(bond_dev); - unsigned long speed = 0; struct list_head *iter; struct slave *slave; + u32 speed = 0;

cmd->base.duplex = DUPLEX_UNKNOWN; cmd->base.port = PORT_OTHER; @@ -4174,8 +4184,13 @@ static int bond_ethtool_get_link_ksettings(struct net_device *bond_dev, */ bond_for_each_slave(bond, slave, iter) { if (bond_slave_can_tx(slave)) { - if (slave->speed != SPEED_UNKNOWN) - speed += slave->speed; + if (slave->speed != SPEED_UNKNOWN) { + if (BOND_MODE(bond) == BOND_MODE_BROADCAST) + speed = bond_mode_bcast_speed(slave, + speed); + else + speed += slave->speed; + } if (cmd->base.duplex == DUPLEX_UNKNOWN && slave->duplex != DUPLEX_UNKNOWN) cmd->base.duplex = slave->duplex;

From: Srinivas Kandagatla srinivas.kandagatla@linaro.org

[ Upstream commit ff69c97ef84c9f7795adb49e9f07c9adcdd0c288 ]

For some reason interrupt set and clear register offsets are not set correctly. This patch corrects them!

Fixes: 585e881e5b9e ("ASoC: codecs: Add msm8916-wcd analog codec") Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org Tested-by: Stephan Gerhold stephan@gerhold.net Reviewed-by: Stephan Gerhold stephan@gerhold.net Link: https://lore.kernel.org/r/20200811103452.20448-1-srinivas.kandagatla@linaro.... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- sound/soc/codecs/msm8916-wcd-analog.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/msm8916-wcd-analog.c b/sound/soc/codecs/msm8916-wcd-analog.c index 3633eb30dd135..4f949ad50d6a7 100644 --- a/sound/soc/codecs/msm8916-wcd-analog.c +++ b/sound/soc/codecs/msm8916-wcd-analog.c @@ -16,8 +16,8 @@

#define CDC_D_REVISION1 (0xf000) #define CDC_D_PERPH_SUBTYPE (0xf005) -#define CDC_D_INT_EN_SET (0x015) -#define CDC_D_INT_EN_CLR (0x016) +#define CDC_D_INT_EN_SET (0xf015) +#define CDC_D_INT_EN_CLR (0xf016) #define MBHC_SWITCH_INT BIT(7) #define MBHC_MIC_ELECTRICAL_INS_REM_DET BIT(6) #define MBHC_BUTTON_PRESS_DET BIT(5)

From: Alex Williamson alex.williamson@redhat.com

[ Upstream commit aae7a75a821a793ed6b8ad502a5890fb8e8f172d ]

The vfio_iommu_replay() function does not currently unwind on error, yet it does pin pages, perform IOMMU mapping, and modify the vfio_dma structure to indicate IOMMU mapping. The IOMMU mappings are torn down when the domain is destroyed, but the other actions go on to cause trouble later. For example, the iommu->domain_list can be empty if we only have a non-IOMMU backed mdev attached. We don't currently check if the list is empty before getting the first entry in the list, which leads to a bogus domain pointer. If a vfio_dma entry is erroneously marked as iommu_mapped, we'll attempt to use that bogus pointer to retrieve the existing physical page addresses.

This is the scenario that uncovered this issue, attempting to hot-add a vfio-pci device to a container with an existing mdev device and DMA mappings, one of which could not be pinned, causing a failure adding the new group to the existing container and setting the conditions for a subsequent attempt to explode.

To resolve this, we can first check if the domain_list is empty so that we can reject replay of a bogus domain, should we ever encounter this inconsistent state again in the future. The real fix though is to add the necessary unwind support, which means cleaning up the current pinning if an IOMMU mapping fails, then walking back through the r-b tree of DMA entries, reading from the IOMMU which ranges are mapped, and unmapping and unpinning those ranges. To be able to do this, we also defer marking the DMA entry as IOMMU mapped until all entries are processed, in order to allow the unwind to know the disposition of each entry.

Fixes: a54eb55045ae ("vfio iommu type1: Add support for mediated devices") Reported-by: Zhiyi Guo zhguo@redhat.com Tested-by: Zhiyi Guo zhguo@redhat.com Reviewed-by: Cornelia Huck cohuck@redhat.com Signed-off-by: Alex Williamson alex.williamson@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/vfio/vfio_iommu_type1.c | 71 ++++++++++++++++++++++++++++++--- 1 file changed, 66 insertions(+), 5 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 35a3750a6ddd3..f22425501bc16 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -1086,13 +1086,16 @@ static int vfio_bus_type(struct device *dev, void *data) static int vfio_iommu_replay(struct vfio_iommu *iommu, struct vfio_domain *domain) { - struct vfio_domain *d; + struct vfio_domain *d = NULL; struct rb_node *n; unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; int ret;

/* Arbitrarily pick the first domain in the list for lookups */ - d = list_first_entry(&iommu->domain_list, struct vfio_domain, next); + if (!list_empty(&iommu->domain_list)) + d = list_first_entry(&iommu->domain_list, + struct vfio_domain, next); + n = rb_first(&iommu->dma_list);

for (; n; n = rb_next(n)) { @@ -1110,6 +1113,11 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, phys_addr_t p; dma_addr_t i;

+ if (WARN_ON(!d)) { /* mapped w/o a domain?! */ + ret = -EINVAL; + goto unwind; + } + phys = iommu_iova_to_phys(d->domain, iova);

if (WARN_ON(!phys)) { @@ -1139,7 +1147,7 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, if (npage <= 0) { WARN_ON(!npage); ret = (int)npage; - return ret; + goto unwind; }

phys = pfn << PAGE_SHIFT; @@ -1148,14 +1156,67 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,

ret = iommu_map(domain->domain, iova, phys, size, dma->prot | domain->prot); - if (ret) - return ret; + if (ret) { + if (!dma->iommu_mapped) + vfio_unpin_pages_remote(dma, iova, + phys >> PAGE_SHIFT, + size >> PAGE_SHIFT, + true); + goto unwind; + }

iova += size; } + } + + /* All dmas are now mapped, defer to second tree walk for unwind */ + for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) { + struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node); + dma->iommu_mapped = true; } + return 0; + +unwind: + for (; n; n = rb_prev(n)) { + struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node); + dma_addr_t iova; + + if (dma->iommu_mapped) { + iommu_unmap(domain->domain, dma->iova, dma->size); + continue; + } + + iova = dma->iova; + while (iova < dma->iova + dma->size) { + phys_addr_t phys, p; + size_t size; + dma_addr_t i; + + phys = iommu_iova_to_phys(domain->domain, iova); + if (!phys) { + iova += PAGE_SIZE; + continue; + } + + size = PAGE_SIZE; + p = phys + size; + i = iova + size; + while (i < dma->iova + dma->size && + p == iommu_iova_to_phys(domain->domain, i)) { + size += PAGE_SIZE; + p += PAGE_SIZE; + i += PAGE_SIZE; + } + + iommu_unmap(domain->domain, iova, size); + vfio_unpin_pages_remote(dma, iova, phys >> PAGE_SHIFT, + size >> PAGE_SHIFT, true); + } + } + + return ret; }

/*

From: Haiyang Zhang haiyangz@microsoft.com

[ Upstream commit c3d897e01aef8ddc43149e4d661b86f823e3aae7 ]

netvsc_vf_xmit() / dev_queue_xmit() will call VF NIC’s ndo_select_queue or netdev_pick_tx() again. They will use skb_get_rx_queue() to get the queue number, so the “skb->queue_mapping - 1” will be used. This may cause the last queue of VF not been used.

Use skb_record_rx_queue() here, so that the skb_get_rx_queue() called later will get the correct queue number, and VF will be able to use all queues.

Fixes: b3bf5666a510 ("hv_netvsc: defer queue selection to VF") Signed-off-by: Haiyang Zhang haiyangz@microsoft.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/hyperv/netvsc_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 10c3480c2da89..dbc6c9ed1c8f8 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -500,7 +500,7 @@ static int netvsc_vf_xmit(struct net_device *net, struct net_device *vf_netdev, int rc;

skb->dev = vf_netdev; - skb->queue_mapping = qdisc_skb_cb(skb)->slave_dev_queue_mapping; + skb_record_rx_queue(skb, qdisc_skb_cb(skb)->slave_dev_queue_mapping);

rc = dev_queue_xmit(skb); if (likely(rc == NET_XMIT_SUCCESS || rc == NET_XMIT_CN)) {

From: Vasant Hegde hegdevasant@linux.vnet.ibm.com

commit 90a9b102eddf6a3f987d15f4454e26a2532c1c98 upstream.

As per PAPR we have to look for both EPOW sensor value and event modifier to identify the type of event and take appropriate action.

In LoPAPR v1.1 section 10.2.2 includes table 136 "EPOW Action Codes":

SYSTEM_SHUTDOWN 3

The system must be shut down. An EPOW-aware OS logs the EPOW error log information, then schedules the system to be shut down to begin after an OS defined delay internal (default is 10 minutes.)

Then in section 10.3.2.2.8 there is table 146 "Platform Event Log Format, Version 6, EPOW Section", which includes the "EPOW Event Modifier":

For EPOW sensor value = 3 0x01 = Normal system shutdown with no additional delay 0x02 = Loss of utility power, system is running on UPS/Battery 0x03 = Loss of system critical functions, system should be shutdown 0x04 = Ambient temperature too high All other values = reserved

We have a user space tool (rtas_errd) on LPAR to monitor for EPOW_SHUTDOWN_ON_UPS. Once it gets an event it initiates shutdown after predefined time. It also starts monitoring for any new EPOW events. If it receives "Power restored" event before predefined time it will cancel the shutdown. Otherwise after predefined time it will shutdown the system.

Commit 79872e35469b ("powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown") changed our handling of the "on UPS/Battery" case, to immediately shutdown the system. This breaks existing setups that rely on the userspace tool to delay shutdown and let the system run on the UPS.

Fixes: 79872e35469b ("powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown") Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Vasant Hegde hegdevasant@linux.vnet.ibm.com [mpe: Massage change log and add PAPR references] Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20200820061844.306460-1-hegdevasant@linux.vnet.ibm... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/powerpc/platforms/pseries/ras.c | 1 - 1 file changed, 1 deletion(-)

--- a/arch/powerpc/platforms/pseries/ras.c +++ b/arch/powerpc/platforms/pseries/ras.c @@ -115,7 +115,6 @@ static void handle_system_shutdown(char case EPOW_SHUTDOWN_ON_UPS: pr_emerg("Loss of system power detected. System is running on" " UPS/battery. Check RTAS error log for details\n"); - orderly_poweroff(true); break;

case EPOW_SHUTDOWN_LOSS_OF_CRITICAL_FUNCTIONS:

From: Al Viro viro@zeniv.linux.org.uk

commit 52c479697c9b73f628140dcdfcd39ea302d05482 upstream.

Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Marc Zyngier maz@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/eventpoll.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)

--- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -2099,10 +2099,8 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, in mutex_lock(&epmutex); if (is_file_epoll(tf.file)) { error = -ELOOP; - if (ep_loop_check(ep, tf.file) != 0) { - clear_tfile_check_list(); + if (ep_loop_check(ep, tf.file) != 0) goto error_tgt_fput; - } } else { get_file(tf.file); list_add(&tf.file->f_tfile_llink, @@ -2131,8 +2129,6 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, in error = ep_insert(ep, &epds, tf.file, fd, full_check); } else error = -EEXIST; - if (full_check) - clear_tfile_check_list(); break; case EPOLL_CTL_DEL: if (epi) @@ -2155,8 +2151,10 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, in mutex_unlock(&ep->mtx);

error_tgt_fput: - if (full_check) + if (full_check) { + clear_tfile_check_list(); mutex_unlock(&epmutex); + }

fdput(tf); error_fput:

From: Juergen Gross jgross@suse.com

For support of long running hypercalls xen_maybe_preempt_hcall() is calling cond_resched() in case a hypercall marked as preemptible has been interrupted.

Normally this is no problem, as only hypercalls done via some ioctl()s are marked to be preemptible. In rare cases when during such a preemptible hypercall an interrupt occurs and any softirq action is started from irq_exit(), a further hypercall issued by the softirq handler will be regarded to be preemptible, too. This might lead to rescheduling in spite of the softirq handler potentially having set preempt_disable(), leading to splats like:

BUG: sleeping function called from invalid context at drivers/xen/preempt.c:37 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 20775, name: xl INFO: lockdep is turned off. CPU: 1 PID: 20775 Comm: xl Tainted: G D W 5.4.46-1_prgmr_debug.el7.x86_64 #1 Call Trace: <IRQ> dump_stack+0x8f/0xd0 ___might_sleep.cold.76+0xb2/0x103 xen_maybe_preempt_hcall+0x48/0x70 xen_do_hypervisor_callback+0x37/0x40 RIP: e030:xen_hypercall_xen_version+0xa/0x20 Code: ... RSP: e02b:ffffc900400dcc30 EFLAGS: 00000246 RAX: 000000000004000d RBX: 0000000000000200 RCX: ffffffff8100122a RDX: ffff88812e788000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff83ee3ad0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: ffff8881824aa0b0 R13: 0000000865496000 R14: 0000000865496000 R15: ffff88815d040000 ? xen_hypercall_xen_version+0xa/0x20 ? xen_force_evtchn_callback+0x9/0x10 ? check_events+0x12/0x20 ? xen_restore_fl_direct+0x1f/0x20 ? _raw_spin_unlock_irqrestore+0x53/0x60 ? debug_dma_sync_single_for_cpu+0x91/0xc0 ? _raw_spin_unlock_irqrestore+0x53/0x60 ? xen_swiotlb_sync_single_for_cpu+0x3d/0x140 ? mlx4_en_process_rx_cq+0x6b6/0x1110 [mlx4_en] ? mlx4_en_poll_rx_cq+0x64/0x100 [mlx4_en] ? net_rx_action+0x151/0x4a0 ? __do_softirq+0xed/0x55b ? irq_exit+0xea/0x100 ? xen_evtchn_do_upcall+0x2c/0x40 ? xen_do_hypervisor_callback+0x29/0x40 </IRQ> ? xen_hypercall_domctl+0xa/0x20 ? xen_hypercall_domctl+0x8/0x20 ? privcmd_ioctl+0x221/0x990 [xen_privcmd] ? do_vfs_ioctl+0xa5/0x6f0 ? ksys_ioctl+0x60/0x90 ? trace_hardirqs_off_thunk+0x1a/0x20 ? __x64_sys_ioctl+0x16/0x20 ? do_syscall_64+0x62/0x250 ? entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fix that by testing preempt_count() before calling cond_resched().

In kernel 5.8 this can't happen any more due to the entry code rework (more than 100 patches, so not a candidate for backporting).

The issue was introduced in kernel 4.3, so this patch should go into all stable kernels in [4.3 ... 5.7].

Reported-by: Sarah Newman srn@prgmr.com Fixes: 0fa2f5cb2b0ecd8 ("sched/preempt, xen: Use need_resched() instead of should_resched()") Cc: Sarah Newman srn@prgmr.com Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross jgross@suse.com Tested-by: Chris Brannon cmb@prgmr.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/xen/preempt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/xen/preempt.c +++ b/drivers/xen/preempt.c @@ -31,7 +31,7 @@ EXPORT_SYMBOL_GPL(xen_in_preemptible_hca asmlinkage __visible void xen_maybe_preempt_hcall(void) { if (unlikely(__this_cpu_read(xen_in_preemptible_hcall) - && need_resched())) { + && need_resched() && !preempt_count())) { /* * Clear flag as we may be rescheduled on a different * cpu.