Subject: devmem, x86: fix rename of CONFIG_NONPROMISC_DEVMEM

From: Arjan van de Ven <arjan@infradead.org>
Date: Sat, 19 Jul 2008 15:47:17 -0700

CONFIG_NONPROMISC_DEVMEM was a rather confusing name - but renaming it
to CONFIG_PROMISC_DEVMEM causes problems on architectures that do not
support this feature; this patch renames it to CONFIG_STRICT_DEVMEM,
so that architectures can opt-in into it.

( the polarity of the option is still the same as it was originally; it
  needs to be for now to not break architectures that don't have the
  infastructure yet to support this feature)

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: "V.Radhakrishnan" <rk@atr-labs.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index f0cf5d9907947c6536ecf07ea5aa224db10623f4..51c8214779513e3c1e1df6b56cda8907d7a9a636 100644 (file)
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -5,14 +5,15 @@ config TRACE_IRQFLAGS_SUPPORT
 
 source "lib/Kconfig.debug"
 
-config PROMISC_DEVMEM
-       bool "Allow unlimited access to /dev/mem"
-       default y
+config STRICT_DEVMEM
+       bool "Filter access to /dev/mem"
        help
          If this option is left on, you allow userspace (root) access to all
          of memory, including kernel and userspace memory. Accidental
          access to this is obviously disastrous, but specific access can
-         be used by people debugging the kernel.
+         be used by people debugging the kernel. Note that with PAT support
+         enabled, even in this case there are restrictions on /dev/mem
+         use due to the cache aliasing requirements.
 
          If this option is switched on, the /dev/mem file only allows
          userspace access to PCI space and the BIOS code and data regions.

diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig
index 9bc34e2033ecf9ec0518f59210449a07414ad5a1..4d73f53287b6acf795c5cdf1ae5197b37f04bfab 100644 (file)
--- a/arch/x86/configs/i386_defconfig
+++ b/arch/x86/configs/i386_defconfig
@@ -2047,7 +2047,7 @@ CONFIG_PROVIDE_OHCI1394_DMA_INIT=y
 # CONFIG_SAMPLES is not set
 # CONFIG_KGDB is not set
 CONFIG_HAVE_ARCH_KGDB=y
-# CONFIG_NONPROMISC_DEVMEM is not set
+# CONFIG_STRICT_DEVMEM is not set
 CONFIG_EARLY_PRINTK=y
 CONFIG_DEBUG_STACKOVERFLOW=y
 CONFIG_DEBUG_STACK_USAGE=y

diff --git a/arch/x86/configs/x86_64_defconfig b/arch/x86/configs/x86_64_defconfig
index ae5124e064d4c881b0d5fa56f0826cdb00c7d8c4..a4045242962552c3c39558c32a68dddfbf867210 100644 (file)
--- a/arch/x86/configs/x86_64_defconfig
+++ b/arch/x86/configs/x86_64_defconfig
@@ -2012,7 +2012,7 @@ CONFIG_PROVIDE_OHCI1394_DMA_INIT=y
 # CONFIG_SAMPLES is not set
 # CONFIG_KGDB is not set
 CONFIG_HAVE_ARCH_KGDB=y
-# CONFIG_NONPROMISC_DEVMEM is not set
+# CONFIG_STRICT_DEVMEM is not set
 CONFIG_EARLY_PRINTK=y
 CONFIG_DEBUG_STACKOVERFLOW=y
 CONFIG_DEBUG_STACK_USAGE=y

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index c34dc483839c3f5c29d72f11cfd779c1f9e34977..6bb597f4d70133e4aefb9db3d8e4b1bec259c804 100644 (file)
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -373,8 +373,8 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
        return vma_prot;
 }
 
-#ifndef CONFIG_PROMISC_DEVMEM
-/* This check is done in drivers/char/mem.c in case of !PROMISC_DEVMEM*/
+#ifdef CONFIG_STRICT_DEVMEM
+/* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM*/
 static inline int range_is_allowed(unsigned long pfn, unsigned long size)
 {
        return 1;
@@ -398,7 +398,7 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size)
        }
        return 1;
 }
-#endif /* CONFIG_PROMISC_DEVMEM */
+#endif /* CONFIG_STRICT_DEVMEM */
 
 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
                                unsigned long size, pgprot_t *vma_prot)

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index de05775bd687c52d8de12087fbe7ef260332ef4c..b6772d657547a4e25f275f2a1bd4bc29ac3188e4 100644 (file)
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -80,7 +80,7 @@ static inline int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
 }
 #endif
 
-#ifndef CONFIG_PROMISC_DEVMEM
+#ifdef CONFIG_STRICT_DEVMEM
 static inline int range_is_allowed(unsigned long pfn, unsigned long size)
 {
        u64 from = ((u64)pfn) << PAGE_SHIFT;