| Message ID | 20170506040747.GF32707@kroah.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 2017-05-05 at 21:07 -0700, Greg KH wrote: > From: Chris Fries <cfries@google.com> > > Add %paP and %padP for physical address that need to always be shown > regardless of kptr restrictions. The commit message could be improved. I had to look at the actual code to see if %papP was supported. > diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt [] > @@ -82,18 +82,20 @@ Struct Resources: > > Physical addresses types phys_addr_t: > > - %pa[p] 0x01234567 or 0x0123456789abcdef > + %pa[p][P] 0x01234567 or 0x0123456789abcdef Well, that's good. > diff --git a/lib/vsprintf.c b/lib/vsprintf.c [] > @@ -1394,23 +1394,29 @@ static noinline_for_stack > char *address_val(char *buf, char *end, const void *addr, const char *fmt) > { > unsigned long long num; > + int cleanse = kptr_restrict_cleanse_addresses(); bool
On Fri, May 05, 2017 at 09:42:40PM -0700, Joe Perches wrote: > On Fri, 2017-05-05 at 21:07 -0700, Greg KH wrote: > > From: Chris Fries <cfries@google.com> > > > > Add %paP and %padP for physical address that need to always be shown > > regardless of kptr restrictions. > > The commit message could be improved. Good point, I'll work on that, thanks. > I had to look at the actual code to see if %papP was supported. > > > diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt > [] > > @@ -82,18 +82,20 @@ Struct Resources: > > > > Physical addresses types phys_addr_t: > > > > - %pa[p] 0x01234567 or 0x0123456789abcdef > > + %pa[p][P] 0x01234567 or 0x0123456789abcdef > > Well, that's good. > > > diff --git a/lib/vsprintf.c b/lib/vsprintf.c > [] > > @@ -1394,23 +1394,29 @@ static noinline_for_stack > > char *address_val(char *buf, char *end, const void *addr, const char *fmt) > > { > > unsigned long long num; > > + int cleanse = kptr_restrict_cleanse_addresses(); > > bool I'll change this, thanks. greg k-h
On Fri 2017-05-05 21:07:47, Greg KH wrote: > From: Chris Fries <cfries@google.com> > > Add %paP and %padP for physical address that need to always be shown > regardless of kptr restrictions. > > Cc: William Roberts <william.c.roberts@intel.com> > Cc: Dave Weinstein <olorin@google.com> > Signed-off-by: Chris Fries <cfries@google.com> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > --- > Documentation/printk-formats.txt | 10 ++++++---- > lib/vsprintf.c | 12 +++++++++--- > 2 files changed, 15 insertions(+), 7 deletions(-) This patch should update also the section about kptr_restrict in Documentation/sysctl/kernel.txt. It should mention that the trailing P allows to see pointers also for %pa, and %p[rR] formats when the level is 4. Best Regards, Petr
On Tue, May 16, 2017 at 04:41:04PM +0200, Petr Mladek wrote: > On Fri 2017-05-05 21:07:47, Greg KH wrote: > > From: Chris Fries <cfries@google.com> > > > > Add %paP and %padP for physical address that need to always be shown > > regardless of kptr restrictions. > > > > Cc: William Roberts <william.c.roberts@intel.com> > > Cc: Dave Weinstein <olorin@google.com> > > Signed-off-by: Chris Fries <cfries@google.com> > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > --- > > Documentation/printk-formats.txt | 10 ++++++---- > > lib/vsprintf.c | 12 +++++++++--- > > 2 files changed, 15 insertions(+), 7 deletions(-) > > This patch should update also the section about > kptr_restrict in Documentation/sysctl/kernel.txt. > It should mention that the trailing P allows to see > pointers also for %pa, and %p[rR] formats when > the level is 4. Ah, good point, will do! greg k-h
diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt index 8994c65aa3b0..7ee51269096f 100644 --- a/Documentation/printk-formats.txt +++ b/Documentation/printk-formats.txt @@ -82,18 +82,20 @@ Struct Resources: Physical addresses types phys_addr_t: - %pa[p] 0x01234567 or 0x0123456789abcdef + %pa[p][P] 0x01234567 or 0x0123456789abcdef For printing a phys_addr_t type (and its derivatives, such as resource_size_t) which can vary based on build options, regardless of - the width of the CPU data path. Passed by reference. + the width of the CPU data path. Passed by reference. Use the trailing + 'P' if it needs to be always shown. DMA addresses types dma_addr_t: - %pad 0x01234567 or 0x0123456789abcdef + %pad[P] 0x01234567 or 0x0123456789abcdef For printing a dma_addr_t type which can vary based on build options, - regardless of the width of the CPU data path. Passed by reference. + regardless of the width of the CPU data path. Passed by reference. Use + the trailing 'P' if it needs to be always shown. Raw buffer as an escaped string: diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 404d477d4bd2..37f9d615e622 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1394,23 +1394,29 @@ static noinline_for_stack char *address_val(char *buf, char *end, const void *addr, const char *fmt) { unsigned long long num; + int cleanse = kptr_restrict_cleanse_addresses(); + int decleanse_idx = 1; int size; switch (fmt[1]) { case 'd': num = *(const dma_addr_t *)addr; size = sizeof(dma_addr_t); + decleanse_idx = 2; break; case 'p': + decleanse_idx = 2; + /* fall thru */ default: num = *(const phys_addr_t *)addr; size = sizeof(phys_addr_t); break; } - return special_hex_number(buf, end, - kptr_restrict_cleanse_addresses() ? 0UL : num, - size); + /* 'P' on the tail means don't restrict the pointer. */ + cleanse = cleanse && (fmt[decleanse_idx] != 'P'); + + return special_hex_number(buf, end, cleanse ? 0UL : num, size); } static noinline_for_stack