search for: __copy_from_user

copy_from_user is pretty high on perf top profile, replacing it with __copy_from_user helps. It's also safe because we do access_ok checks during setup. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index ade0568..01701...

copy_from_user is pretty high on perf top profile, replacing it with __copy_from_user helps. It's also safe because we do access_ok checks during setup. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index ade0568..01701...

...>> arch/m68k/include/asm/uaccess_mm.h:368:2: warning: passing argument 2 of '__constant_copy_from_user' makes pointer from integer without a cast __constant_copy_from_user(to, from, n) : \ ^ >> arch/m68k/include/asm/uaccess_mm.h:379:37: note: in expansion of macro '__copy_from_user' #define copy_from_user(to, from, n) __copy_from_user(to, from, n) ^ drivers/gpu/drm/vc4/vc4_bo.c:502:6: note: in expansion of macro 'copy_from_user' if (copy_from_user(bo->base.vaddr, ^ arch/m68k/include/asm/uaccess_mm....

Use the newly added u64_to_user_pointer a bit more frequently. Signed-off-by: Joe Perches <joe at perches.com> --- drivers/gpu/drm/armada/armada_gem.c | 2 +- drivers/gpu/drm/nouveau/nouveau_gem.c | 7 ++++--- drivers/gpu/drm/tegra/drm.c | 15 ++++++++------- drivers/gpu/drm/vc4/vc4_bo.c | 4 ++-- drivers/gpu/drm/vc4/vc4_gem.c | 10 +++++-----

Use the newly added u64_to_user_pointer a bit more frequently. Signed-off-by: Joe Perches <joe at perches.com> --- drivers/gpu/drm/armada/armada_gem.c | 2 +- drivers/gpu/drm/nouveau/nouveau_gem.c | 7 ++++--- drivers/gpu/drm/tegra/drm.c | 15 ++++++++------- drivers/gpu/drm/vc4/vc4_bo.c | 4 ++-- drivers/gpu/drm/vc4/vc4_gem.c | 10 +++++-----

...rs/vhost/vhost.c b/drivers/vhost/vhost.c > index f44340b41494..b23d1b74c32f 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -824,34 +824,32 @@ static int vhost_copy_from_user(struct vhost_virtqueue *vq, void *to, > > if (!vq->iotlb) > return __copy_from_user(to, from, size); > - else { > - /* This function should be called after iotlb > - * prefetch, which means we're sure that vq > - * could be access through iotlb. So -EAGAIN should > - * not happen in this case. > - */ > - void __user *uaddr = vhost_vq_meta_fetch(v...

...: check the support of mergeable buffer outside the receive loop vhost-net: Unify the code of mergeable and big buffer handling vhost: lock receive queue, not the socket Krishna Kumar (1): vhost: Cleanup vhost.c and net.c Michael S. Tsirkin (2): vhost: copy_from_user -> __copy_from_user vhost-net: remove unlocked use of receive_queue drivers/vhost/net.c | 159 ++++++++----------------------------------------- drivers/vhost/vhost.c | 55 ++++++++++++----- 2 files changed, 64 insertions(+), 150 deletions(-)

...: check the support of mergeable buffer outside the receive loop vhost-net: Unify the code of mergeable and big buffer handling vhost: lock receive queue, not the socket Krishna Kumar (1): vhost: Cleanup vhost.c and net.c Michael S. Tsirkin (2): vhost: copy_from_user -> __copy_from_user vhost-net: remove unlocked use of receive_queue drivers/vhost/net.c | 159 ++++++++----------------------------------------- drivers/vhost/vhost.c | 55 ++++++++++++----- 2 files changed, 64 insertions(+), 150 deletions(-)

1: correct LDT checks 2: add address validity check to guest_map_l1e() 3: use {rd,wr}{fs,gs}base when available 4: check for canonical address before doing page walks Signed-off-by: Jan Beulich <jbeulich@suse.com>

...;vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { vq_err(vq, "Failed to read head: idx %d address %p\n", last_avail_idx, @@ -1450,7 +1450,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = __copy_from_user(&desc, vq->desc + i, sizeof desc); + ret = __copy_from_user_mm(vq->dev->mm, &desc, vq->desc + i, sizeof desc); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); @@ -1622,7 +1622,7 @@ static bool vhost_...

...;vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { vq_err(vq, "Failed to read head: idx %d address %p\n", last_avail_idx, @@ -1450,7 +1450,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = __copy_from_user(&desc, vq->desc + i, sizeof desc); + ret = __copy_from_user_mm(vq->dev->mm, &desc, vq->desc + i, sizeof desc); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); @@ -1622,7 +1622,7 @@ static bool vhost_...

While working on a database scaling problem using a SAP database test suite we discovered that these enterprise level large shared memory databases are very heavy users of mprotect(), to the extent that the performance overhead in current Xenolinux impacts scaling beyond a few cpus quite badly. A single cpu run under Xen has a nominal impact, but scaling out to 8 cpus results in a performance of

...copy_to_user(&shadow_linear_pg_table[va >> PAGE_SHIFT], + &zero, sizeof(zero))) { vmx_shadow_clear_state(ed->domain); return; } - if (__get_user(gpte, (unsigned long *) - &linear_pg_table[va >> PAGE_SHIFT])) { + if (__copy_from_user(&gpte, + &linear_pg_table[va >> PAGE_SHIFT], + sizeof(gpte))) { return; } l1pte_propagate_from_guest(ed->domain, &gpte, &spte); - if (__put_user(spte, (unsigned long *) - &shadow_linear_pg_table[va >> PAGE_SHIFT]))...

...) > + return NULL; > + > + len = sizeof(pkt->hdr); > + if (unlikely(vq->iov[0].iov_len != len)) { > + vq_err(vq, "Expecting pkt->hdr = %d, got %zu bytes\n", > + len, vq->iov[0].iov_len); > + kfree(pkt); > + return NULL; > + } > + ret = __copy_from_user(&pkt->hdr, vq->iov[0].iov_base, len); > + if (ret) { > + vq_err(vq, "Faulted on virtio_vsock_hdr\n"); > + kfree(pkt); > + return NULL; > + } > + > + pkt->len = pkt->hdr.len; > + pkt->off = 0; > + > + /* No payload */ > + if (!pkt->...

...) > + return NULL; > + > + len = sizeof(pkt->hdr); > + if (unlikely(vq->iov[0].iov_len != len)) { > + vq_err(vq, "Expecting pkt->hdr = %d, got %zu bytes\n", > + len, vq->iov[0].iov_len); > + kfree(pkt); > + return NULL; > + } > + ret = __copy_from_user(&pkt->hdr, vq->iov[0].iov_base, len); > + if (ret) { > + vq_err(vq, "Faulted on virtio_vsock_hdr\n"); > + kfree(pkt); > + return NULL; > + } > + > + pkt->len = pkt->hdr.len; > + pkt->off = 0; > + > + /* No payload */ > + if (!pkt->...

...dx & (vq->num - 1)]))) { > vq_err(vq, "Failed to read head: idx %d address %p\n", > last_avail_idx, > @@ -1450,7 +1450,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, > i, vq->num, head); > return -EINVAL; > } > - ret = __copy_from_user(&desc, vq->desc + i, sizeof desc); > + ret = __copy_from_user_mm(vq->dev->mm, &desc, vq->desc + i, sizeof desc); > if (unlikely(ret)) { > vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", > i, vq->desc + i); > @@ -1622,7 +162...

...kt = kzalloc(sizeof(*pkt), GFP_KERNEL); + if (!pkt) + return NULL; + + len = sizeof(pkt->hdr); + if (unlikely(vq->iov[0].iov_len != len)) { + vq_err(vq, "Expecting pkt->hdr = %d, got %zu bytes\n", + len, vq->iov[0].iov_len); + kfree(pkt); + return NULL; + } + ret = __copy_from_user(&pkt->hdr, vq->iov[0].iov_base, len); + if (ret) { + vq_err(vq, "Faulted on virtio_vsock_hdr\n"); + kfree(pkt); + return NULL; + } + + pkt->len = pkt->hdr.len; + pkt->off = 0; + + /* No payload */ + if (!pkt->len) + return pkt; + + /* The pkt is too big */ + if (...

...s(d, gpfn, PGT_snapshot); - l1_pgentry_t *snapshot; // could be L1s or L2s or ... + l1_pgentry_t *snapshot, gpte; // could be L1s or L2s or ... int entries_match; perfc_incrc(snapshot_entry_matches_calls); @@ -1916,10 +1916,14 @@ snapshot = map_domain_page(smfn); + if (__copy_from_user(&gpte, &guest_pt[index], + sizeof(gpte))) + return 0; + // This could probably be smarter, but this is sufficent for // our current needs. // - entries_match = !l1e_has_changed(guest_pt[index], snapshot[index], + entries_match = !l1e_has_c...

...6/include/asm/smap.h:stac Cyclomatic Complexity 1 arch/x86/include/asm/uaccess.h:set_fs Cyclomatic Complexity 1 arch/x86/include/asm/uaccess_32.h:raw_copy_to_user Cyclomatic Complexity 5 arch/x86/include/asm/uaccess_32.h:raw_copy_from_user Cyclomatic Complexity 1 include/linux/uaccess.h:__copy_from_user Cyclomatic Complexity 1 include/linux/uaccess.h:__copy_to_user Cyclomatic Complexity 2 include/linux/uaccess.h:copy_from_user Cyclomatic Complexity 2 include/linux/uaccess.h:copy_to_user Cyclomatic Complexity 4 include/linux/poll.h:poll_wait Cyclomatic Complexity 1 include/linux/poll...

...     show_execution_state(regs); > -        regs->eip = (unsigned long)eip; > -        return; > -    } > - > -    /* WARN, BUG or ASSERT: decode the filename pointer and line number. */ > +    /* Decode first pointer argument. */ >     if ( !is_kernel(eip) || >          __copy_from_user(&bug_str, eip, sizeof(bug_str)) || >          (bug_str.mov != 0xbc) ) >         goto die; > -    filename = bug_str(bug_str, eip); > +    p = bug_str(bug_str, eip); > +    if ( !is_kernel(p) ) > +        goto die; >     eip += sizeof(bug_str); > > -    if ( !is_kernel...