Hi David, On 03/04/2011 02:12 PM, David Cohen wrote: > Hi, > > [snip] > >> Sorry, I should've mentioned: I'm using your media-0005-omap3isp branch >> based on 2.6.38-rc5. I didn't have the problem with 2.6.37, either. >> It's actually not related to mis-configuring the ISP pipeline like I >> thought at first- it also happens after I have successfully captured images. >> >> I've since tracked down the problem, although I don't understand the >> cache management well enough to be sure it's a proper fix, so hopefully >> some new recipients on this can make suggestions/comments. >> >> The patch below solves the problem, which modifies a commit by Fernando >> Guzman Lugo from December. >> >> -Michael >> >> From db35fb8edca2a4f8fd37197d77fd58676cb1dcac Mon Sep 17 00:00:00 2001 >> From: Michael Jones <michael.jo...@matrix-vision.de> >> Date: Thu, 3 Mar 2011 16:50:39 +0100 >> Subject: [PATCH] fix iovmm slab cache error on module unload >> >> modify "OMAP: iommu: create new api to set valid da range" >> >> This modifies commit c7f4ab26e3bcdaeb3e19ec658e3ad9092f1a6ceb. >> --- >> arch/arm/plat-omap/iovmm.c | 5 ++++- >> 1 files changed, 4 insertions(+), 1 deletions(-) >> >> diff --git a/arch/arm/plat-omap/iovmm.c b/arch/arm/plat-omap/iovmm.c >> index 6dc1296..2fba6f1 100644 >> --- a/arch/arm/plat-omap/iovmm.c >> +++ b/arch/arm/plat-omap/iovmm.c >> @@ -280,7 +280,10 @@ static struct iovm_struct *alloc_iovm_area(struct iommu >> *obj, u32 da, >> alignement = PAGE_SIZE; >> >> if (flags & IOVMF_DA_ANON) { >> - start = obj->da_start; >> + /* >> + * Reserve the first page for NULL >> + */ >> + start = obj->da_start + PAGE_SIZE; > > IMO if obj->da_start != 0, no need to add PAGE_SIZE. Otherwise, it > does make sense to correct wrong obj->da_start == 0. Another thing is > this piece of code is using alignement (alignment) variable instead of > PAGE_SIZE (which is the same value). > > Br, > > David
I believe the following patch addresses your comments. I couldn't resist also fixing the misspelling of alignment when I was using the variable in my patch. -Michael >From 2712f2fd087ca782e964c912c7f1973e7d84f2b7 Mon Sep 17 00:00:00 2001 From: Michael Jones <michael.jo...@matrix-vision.de> Date: Fri, 4 Mar 2011 15:09:48 +0100 Subject: [PATCH] omap: iovmm: disallow mapping NULL address commit c7f4ab26e3bcdaeb3e19ec658e3ad9092f1a6ceb allowed mapping the NULL address if da_start==0, which would then not get unmapped. Disallow this again. And spell variable 'alignment' correctly. Signed-off-by: Michael Jones <michael.jo...@matrix-vision.de> --- arch/arm/plat-omap/iovmm.c | 16 ++++++++++------ 1 files changed, 10 insertions(+), 6 deletions(-) diff --git a/arch/arm/plat-omap/iovmm.c b/arch/arm/plat-omap/iovmm.c index 6dc1296..11c9b76 100644 --- a/arch/arm/plat-omap/iovmm.c +++ b/arch/arm/plat-omap/iovmm.c @@ -271,20 +271,24 @@ static struct iovm_struct *alloc_iovm_area(struct iommu *obj, u32 da, size_t bytes, u32 flags) { struct iovm_struct *new, *tmp; - u32 start, prev_end, alignement; + u32 start, prev_end, alignment; if (!obj || !bytes) return ERR_PTR(-EINVAL); start = da; - alignement = PAGE_SIZE; + alignment = PAGE_SIZE; if (flags & IOVMF_DA_ANON) { - start = obj->da_start; + /* Don't map address 0 */ + if (obj->da_start) + start = obj->da_start; + else + start = obj->da_start + alignment; if (flags & IOVMF_LINEAR) - alignement = iopgsz_max(bytes); - start = roundup(start, alignement); + alignment = iopgsz_max(bytes); + start = roundup(start, alignment); } else if (start < obj->da_start || start > obj->da_end || obj->da_end - start < bytes) { return ERR_PTR(-EINVAL); @@ -304,7 +308,7 @@ static struct iovm_struct *alloc_iovm_area(struct iommu *obj, u32 da, goto found; if (tmp->da_end >= start && flags & IOVMF_DA_ANON) - start = roundup(tmp->da_end + 1, alignement); + start = roundup(tmp->da_end + 1, alignment); prev_end = tmp->da_end; } -- 1.7.4.1 MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler Registergericht: Amtsgericht Stuttgart, HRB 271090 Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html