From: Christoph Hellwig <hch@lst.de> Date: Tue, 2 Jun 2020 04:50:58 +0000 (-0700) Subject: mm: only allow page table mappings for built-in zsmalloc X-Git-Tag: v5.8-rc1~201^2~29 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b607e6d17db5b91e6a807b4f9a2e849219d720a0;p=users%2Fjedix%2Flinux-maple.git mm: only allow page table mappings for built-in zsmalloc This allows to unexport map_vm_area and unmap_kernel_range, which are rather deep internal and should not be available to modules, as they for example allow fine grained control of mapping permissions, and also allow splitting the setup of a vmalloc area and the actual mapping and thus expose vmalloc internals. zsmalloc is typically built-in and continues to work (just like the percpu-vm code using a similar patter), while modular zsmalloc also continues to work, but must use copies. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Gao Xiang <xiang@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Kelley <mikelley@microsoft.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200414131348.444715-12-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- diff --git a/mm/Kconfig b/mm/Kconfig index 09a9edfb8461..5c0362bd8d56 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -707,7 +707,7 @@ config ZSMALLOC config ZSMALLOC_PGTABLE_MAPPING bool "Use page table mapping to access object in zsmalloc" - depends on ZSMALLOC + depends on ZSMALLOC=y help By default, zsmalloc uses a copy-based object mapping method to access allocations that span two pages. However, if a particular diff --git a/mm/vmalloc.c b/mm/vmalloc.c index af60c43c643e..d4c13229ddc2 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2047,7 +2047,6 @@ void unmap_kernel_range(unsigned long addr, unsigned long size) vunmap_page_range(addr, end); flush_tlb_kernel_range(addr, end); } -EXPORT_SYMBOL_GPL(unmap_kernel_range); int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page **pages) { @@ -2059,7 +2058,6 @@ int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page **pages) return err > 0 ? 0 : err; } -EXPORT_SYMBOL_GPL(map_vm_area); static inline void setup_vmalloc_vm_locked(struct vm_struct *vm, struct vmap_area *va, unsigned long flags, const void *caller)