Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755476Ab3JHOzu (ORCPT ); Tue, 8 Oct 2013 10:55:50 -0400 Received: from mail-qa0-f50.google.com ([209.85.216.50]:43540 "EHLO mail-qa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754095Ab3JHOzt (ORCPT ); Tue, 8 Oct 2013 10:55:49 -0400 Date: Tue, 8 Oct 2013 10:55:41 -0400 From: Jerome Glisse To: Christian =?iso-8859-1?Q?K=F6nig?= Cc: Maarten Lankhorst , Thomas Hellstrom , Peter Zijlstra , Daniel Vetter , intel-gfx , Linux Kernel Mailing List , dri-devel , Alex Deucher , Thomas Gleixner , Ingo Molnar Subject: Re: [RFC PATCH] drm/radeon: fixup locking inversion between mmap_sem and reservations Message-ID: <20131008145540.GB2355@gmail.com> References: <20130912150645.GZ31370@twins.programming.kicks-ass.net> <5231E18D.7070306@canonical.com> <5231EF5A.7010901@vmware.com> <52323734.4070908@canonical.com> <5232A39B.5040205@vmware.com> <52541350.5060807@canonical.com> <20131008143354.GA2355@gmail.com> <52541A7E.6050807@vodafone.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <52541A7E.6050807@vodafone.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12906 Lines: 350 On Tue, Oct 08, 2013 at 04:45:18PM +0200, Christian K?nig wrote: > Am 08.10.2013 16:33, schrieb Jerome Glisse: > >On Tue, Oct 08, 2013 at 04:14:40PM +0200, Maarten Lankhorst wrote: > >>Allocate and copy all kernel memory before doing reservations. This prevents a locking > >>inversion between mmap_sem and reservation_class, and allows us to drop the trylocking > >>in ttm_bo_vm_fault without upsetting lockdep. > >> > >>Signed-off-by: Maarten Lankhorst > >I would say NAK. Current code only allocate temporary page in AGP case. > >So AGP case is userspace -> temp page -> cs checker -> radeon ib. > > > >Non AGP is directly memcpy to radeon IB. > > > >Your patch allocate memory memcpy userspace to it and it will then be > >memcpy to IB. Which means you introduce an extra memcpy in the process > >not something we want. > > Totally agree. Additional to that there is no good reason to provide > anything else than anonymous system memory to the CS ioctl, so the > dependency between the mmap_sem and reservations are not really > clear to me. > > Christian. I think is that in other code path you take mmap_sem first then reserve bo. But here we reserve bo and then we take mmap_sem because of copy from user. Cheers, Jerome > > >Cheers, > >Jerome > > > >>--- > >>diff --git a/drivers/gpu/drm/radeon/r600_cs.c b/drivers/gpu/drm/radeon/r600_cs.c > >>index 01a3ec8..efa9bca 100644 > >>--- a/drivers/gpu/drm/radeon/r600_cs.c > >>+++ b/drivers/gpu/drm/radeon/r600_cs.c > >>@@ -2391,18 +2391,13 @@ int r600_cs_legacy(struct drm_device *dev, void *data, struct drm_file *filp, > >> ib_chunk = &parser.chunks[parser.chunk_ib_idx]; > >> parser.ib.length_dw = ib_chunk->length_dw; > >> *l = parser.ib.length_dw; > >>+ memcpy(ib, ib_chunk->kdata, ib_chunk->length_dw * 4); > >> r = r600_cs_parse(&parser); > >> if (r) { > >> DRM_ERROR("Invalid command stream !\n"); > >> r600_cs_parser_fini(&parser, r); > >> return r; > >> } > >>- r = radeon_cs_finish_pages(&parser); > >>- if (r) { > >>- DRM_ERROR("Invalid command stream !\n"); > >>- r600_cs_parser_fini(&parser, r); > >>- return r; > >>- } > >> r600_cs_parser_fini(&parser, r); > >> return r; > >> } > >>diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h > >>index e067024..c52bb5e 100644 > >>--- a/drivers/gpu/drm/radeon/radeon.h > >>+++ b/drivers/gpu/drm/radeon/radeon.h > >>@@ -983,12 +983,7 @@ struct radeon_cs_reloc { > >> struct radeon_cs_chunk { > >> uint32_t chunk_id; > >> uint32_t length_dw; > >>- int kpage_idx[2]; > >>- uint32_t *kpage[2]; > >> uint32_t *kdata; > >>- void __user *user_ptr; > >>- int last_copied_page; > >>- int last_page_index; > >> }; > >> struct radeon_cs_parser { > >>@@ -1027,8 +1022,13 @@ struct radeon_cs_parser { > >> struct radeon_sa_bo *cpu_sema; > >> }; > >>-extern int radeon_cs_finish_pages(struct radeon_cs_parser *p); > >>-extern u32 radeon_get_ib_value(struct radeon_cs_parser *p, int idx); > >>+static inline u32 radeon_get_ib_value(struct radeon_cs_parser *p, int idx) > >>+{ > >>+ struct radeon_cs_chunk *ibc = &p->chunks[p->chunk_ib_idx]; > >>+ > >>+ return ibc->kdata[idx]; > >>+} > >>+ > >> struct radeon_cs_packet { > >> unsigned idx; > >>diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c > >>index 7d7322e..98d8898 100644 > >>--- a/drivers/gpu/drm/radeon/radeon_cs.c > >>+++ b/drivers/gpu/drm/radeon/radeon_cs.c > >>@@ -217,9 +217,7 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data) > >> return -EFAULT; > >> } > >> p->chunks[i].length_dw = user_chunk.length_dw; > >>- p->chunks[i].kdata = NULL; > >> p->chunks[i].chunk_id = user_chunk.chunk_id; > >>- p->chunks[i].user_ptr = (void __user *)(unsigned long)user_chunk.chunk_data; > >> if (p->chunks[i].chunk_id == RADEON_CHUNK_ID_RELOCS) { > >> p->chunk_relocs_idx = i; > >> } > >>@@ -242,25 +240,22 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data) > >> return -EINVAL; > >> } > >>- cdata = (uint32_t *)(unsigned long)user_chunk.chunk_data; > >>- if ((p->chunks[i].chunk_id == RADEON_CHUNK_ID_RELOCS) || > >>- (p->chunks[i].chunk_id == RADEON_CHUNK_ID_FLAGS)) { > >>- size = p->chunks[i].length_dw * sizeof(uint32_t); > >>- p->chunks[i].kdata = kmalloc(size, GFP_KERNEL); > >>- if (p->chunks[i].kdata == NULL) { > >>- return -ENOMEM; > >>- } > >>- if (DRM_COPY_FROM_USER(p->chunks[i].kdata, > >>- p->chunks[i].user_ptr, size)) { > >>- return -EFAULT; > >>- } > >>- if (p->chunks[i].chunk_id == RADEON_CHUNK_ID_FLAGS) { > >>- p->cs_flags = p->chunks[i].kdata[0]; > >>- if (p->chunks[i].length_dw > 1) > >>- ring = p->chunks[i].kdata[1]; > >>- if (p->chunks[i].length_dw > 2) > >>- priority = (s32)p->chunks[i].kdata[2]; > >>- } > >>+ size = p->chunks[i].length_dw; > >>+ p->chunks[i].kdata = drm_malloc_ab(size, sizeof(uint32_t)); > >>+ size *= sizeof(uint32_t); > >>+ if (p->chunks[i].kdata == NULL) { > >>+ return -ENOMEM; > >>+ } > >>+ cdata = (void __user *)(unsigned long)user_chunk.chunk_data; > >>+ if (DRM_COPY_FROM_USER(p->chunks[i].kdata, cdata, size)) { > >>+ return -EFAULT; > >>+ } > >>+ if (p->chunks[i].chunk_id == RADEON_CHUNK_ID_FLAGS) { > >>+ p->cs_flags = p->chunks[i].kdata[0]; > >>+ if (p->chunks[i].length_dw > 1) > >>+ ring = p->chunks[i].kdata[1]; > >>+ if (p->chunks[i].length_dw > 2) > >>+ priority = (s32)p->chunks[i].kdata[2]; > >> } > >> } > >>@@ -283,34 +278,6 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data) > >> } > >> } > >>- /* deal with non-vm */ > >>- if ((p->chunk_ib_idx != -1) && > >>- ((p->cs_flags & RADEON_CS_USE_VM) == 0) && > >>- (p->chunks[p->chunk_ib_idx].chunk_id == RADEON_CHUNK_ID_IB)) { > >>- if (p->chunks[p->chunk_ib_idx].length_dw > (16 * 1024)) { > >>- DRM_ERROR("cs IB too big: %d\n", > >>- p->chunks[p->chunk_ib_idx].length_dw); > >>- return -EINVAL; > >>- } > >>- if (p->rdev && (p->rdev->flags & RADEON_IS_AGP)) { > >>- p->chunks[p->chunk_ib_idx].kpage[0] = kmalloc(PAGE_SIZE, GFP_KERNEL); > >>- p->chunks[p->chunk_ib_idx].kpage[1] = kmalloc(PAGE_SIZE, GFP_KERNEL); > >>- if (p->chunks[p->chunk_ib_idx].kpage[0] == NULL || > >>- p->chunks[p->chunk_ib_idx].kpage[1] == NULL) { > >>- kfree(p->chunks[p->chunk_ib_idx].kpage[0]); > >>- kfree(p->chunks[p->chunk_ib_idx].kpage[1]); > >>- p->chunks[p->chunk_ib_idx].kpage[0] = NULL; > >>- p->chunks[p->chunk_ib_idx].kpage[1] = NULL; > >>- return -ENOMEM; > >>- } > >>- } > >>- p->chunks[p->chunk_ib_idx].kpage_idx[0] = -1; > >>- p->chunks[p->chunk_ib_idx].kpage_idx[1] = -1; > >>- p->chunks[p->chunk_ib_idx].last_copied_page = -1; > >>- p->chunks[p->chunk_ib_idx].last_page_index = > >>- ((p->chunks[p->chunk_ib_idx].length_dw * 4) - 1) / PAGE_SIZE; > >>- } > >>- > >> return 0; > >> } > >>@@ -450,13 +417,8 @@ static void radeon_cs_parser_fini(struct radeon_cs_parser *parser, int error, bo > >> kfree(parser->track); > >> kfree(parser->relocs); > >> kfree(parser->relocs_ptr); > >>- for (i = 0; i < parser->nchunks; i++) { > >>- kfree(parser->chunks[i].kdata); > >>- if ((parser->rdev->flags & RADEON_IS_AGP)) { > >>- kfree(parser->chunks[i].kpage[0]); > >>- kfree(parser->chunks[i].kpage[1]); > >>- } > >>- } > >>+ for (i = 0; i < parser->nchunks; i++) > >>+ drm_free_large(parser->chunks[i].kdata); > >> kfree(parser->chunks); > >> kfree(parser->chunks_array); > >> radeon_ib_free(parser->rdev, &parser->ib); > >>@@ -483,17 +445,15 @@ static int radeon_cs_ib_chunk(struct radeon_device *rdev, > >> DRM_ERROR("Failed to get ib !\n"); > >> return r; > >> } > >>+ > >>+ memcpy(parser->ib.ptr, ib_chunk->kdata, ib_chunk->length_dw * 4); > >> parser->ib.length_dw = ib_chunk->length_dw; > >>+ > >> r = radeon_cs_parse(rdev, parser->ring, parser); > >> if (r || parser->parser_error) { > >> DRM_ERROR("Invalid command stream !\n"); > >> return r; > >> } > >>- r = radeon_cs_finish_pages(parser); > >>- if (r) { > >>- DRM_ERROR("Invalid command stream !\n"); > >>- return r; > >>- } > >> if (parser->ring == R600_RING_TYPE_UVD_INDEX) > >> radeon_uvd_note_usage(rdev); > >>@@ -555,10 +515,8 @@ static int radeon_cs_ib_vm_chunk(struct radeon_device *rdev, > >> parser->const_ib.is_const_ib = true; > >> parser->const_ib.length_dw = ib_chunk->length_dw; > >> /* Copy the packet into the IB */ > >>- if (DRM_COPY_FROM_USER(parser->const_ib.ptr, ib_chunk->user_ptr, > >>- ib_chunk->length_dw * 4)) { > >>- return -EFAULT; > >>- } > >>+ memcpy(parser->const_ib.ptr, ib_chunk->kdata, > >>+ ib_chunk->length_dw * 4); > >> r = radeon_ring_ib_parse(rdev, parser->ring, &parser->const_ib); > >> if (r) { > >> return r; > >>@@ -578,10 +536,7 @@ static int radeon_cs_ib_vm_chunk(struct radeon_device *rdev, > >> } > >> parser->ib.length_dw = ib_chunk->length_dw; > >> /* Copy the packet into the IB */ > >>- if (DRM_COPY_FROM_USER(parser->ib.ptr, ib_chunk->user_ptr, > >>- ib_chunk->length_dw * 4)) { > >>- return -EFAULT; > >>- } > >>+ memcpy(parser->ib.ptr, ib_chunk->kdata, ib_chunk->length_dw * 4); > >> r = radeon_ring_ib_parse(rdev, parser->ring, &parser->ib); > >> if (r) { > >> return r; > >>@@ -704,97 +659,6 @@ int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp) > >> return r; > >> } > >>-int radeon_cs_finish_pages(struct radeon_cs_parser *p) > >>-{ > >>- struct radeon_cs_chunk *ibc = &p->chunks[p->chunk_ib_idx]; > >>- int i; > >>- int size = PAGE_SIZE; > >>- > >>- for (i = ibc->last_copied_page + 1; i <= ibc->last_page_index; i++) { > >>- if (i == ibc->last_page_index) { > >>- size = (ibc->length_dw * 4) % PAGE_SIZE; > >>- if (size == 0) > >>- size = PAGE_SIZE; > >>- } > >>- > >>- if (DRM_COPY_FROM_USER(p->ib.ptr + (i * (PAGE_SIZE/4)), > >>- ibc->user_ptr + (i * PAGE_SIZE), > >>- size)) > >>- return -EFAULT; > >>- } > >>- return 0; > >>-} > >>- > >>-static int radeon_cs_update_pages(struct radeon_cs_parser *p, int pg_idx) > >>-{ > >>- int new_page; > >>- struct radeon_cs_chunk *ibc = &p->chunks[p->chunk_ib_idx]; > >>- int i; > >>- int size = PAGE_SIZE; > >>- bool copy1 = (p->rdev && (p->rdev->flags & RADEON_IS_AGP)) ? > >>- false : true; > >>- > >>- for (i = ibc->last_copied_page + 1; i < pg_idx; i++) { > >>- if (DRM_COPY_FROM_USER(p->ib.ptr + (i * (PAGE_SIZE/4)), > >>- ibc->user_ptr + (i * PAGE_SIZE), > >>- PAGE_SIZE)) { > >>- p->parser_error = -EFAULT; > >>- return 0; > >>- } > >>- } > >>- > >>- if (pg_idx == ibc->last_page_index) { > >>- size = (ibc->length_dw * 4) % PAGE_SIZE; > >>- if (size == 0) > >>- size = PAGE_SIZE; > >>- } > >>- > >>- new_page = ibc->kpage_idx[0] < ibc->kpage_idx[1] ? 0 : 1; > >>- if (copy1) > >>- ibc->kpage[new_page] = p->ib.ptr + (pg_idx * (PAGE_SIZE / 4)); > >>- > >>- if (DRM_COPY_FROM_USER(ibc->kpage[new_page], > >>- ibc->user_ptr + (pg_idx * PAGE_SIZE), > >>- size)) { > >>- p->parser_error = -EFAULT; > >>- return 0; > >>- } > >>- > >>- /* copy to IB for non single case */ > >>- if (!copy1) > >>- memcpy((void *)(p->ib.ptr+(pg_idx*(PAGE_SIZE/4))), ibc->kpage[new_page], size); > >>- > >>- ibc->last_copied_page = pg_idx; > >>- ibc->kpage_idx[new_page] = pg_idx; > >>- > >>- return new_page; > >>-} > >>- > >>-u32 radeon_get_ib_value(struct radeon_cs_parser *p, int idx) > >>-{ > >>- struct radeon_cs_chunk *ibc = &p->chunks[p->chunk_ib_idx]; > >>- u32 pg_idx, pg_offset; > >>- u32 idx_value = 0; > >>- int new_page; > >>- > >>- pg_idx = (idx * 4) / PAGE_SIZE; > >>- pg_offset = (idx * 4) % PAGE_SIZE; > >>- > >>- if (ibc->kpage_idx[0] == pg_idx) > >>- return ibc->kpage[0][pg_offset/4]; > >>- if (ibc->kpage_idx[1] == pg_idx) > >>- return ibc->kpage[1][pg_offset/4]; > >>- > >>- new_page = radeon_cs_update_pages(p, pg_idx); > >>- if (new_page < 0) { > >>- p->parser_error = new_page; > >>- return 0; > >>- } > >>- > >>- idx_value = ibc->kpage[new_page][pg_offset/4]; > >>- return idx_value; > >>-} > >>- > >> /** > >> * radeon_cs_packet_parse() - parse cp packet and point ib index to next packet > >> * @parser: parser structure holding parsing context. > >> > >>_______________________________________________ > >>dri-devel mailing list > >>dri-devel@lists.freedesktop.org > >>http://lists.freedesktop.org/mailman/listinfo/dri-devel > >_______________________________________________ > >dri-devel mailing list > >dri-devel@lists.freedesktop.org > >http://lists.freedesktop.org/mailman/listinfo/dri-devel > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/