Messages in this thread | | | Date | Fri, 19 Jul 2013 09:59:47 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH v3] x86, tboot: iomem fixes |
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* Ren, Qiaowei <qiaowei.ren@intel.com> wrote:
> On 2013-07-18, Ingo Molnar wrote: > > > > * Qiaowei Ren <qiaowei.ren@intel.com> wrote: > > > >> Current code doesn't use specific interface to access I/O space. > >> So some potential bugs can be caused. We can fix this by using > >> specific API. > > > > This is still very vague. > > > >> > >> Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com> > >> --- > >> arch/x86/kernel/tboot.c | 21 ++++++++++++--------- > >> 1 file changed, 12 insertions(+), 9 deletions(-) > >> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index > >> 3ff42d2..afe8cf8 100644 > >> --- a/arch/x86/kernel/tboot.c > >> +++ b/arch/x86/kernel/tboot.c > >> @@ -466,9 +466,12 @@ struct sinit_mle_data { > >> u32 vtd_dmars_off; > >> } __packed; > >> +#define SINIT_MLE_DATA_VTD_DMAR_OFF 140 > >> + > >> struct acpi_table_header *tboot_get_dmar_table(struct > >> acpi_table_header *dmar_tbl) { > >> - void *heap_base, *heap_ptr, *config; > >> + void __iomem *heap_base, *heap_ptr, *config; > >> + u32 dmar_tbl_off; > >> > >> if (!tboot_enabled()) > >> return dmar_tbl; > >> @@ -485,25 +488,25 @@ struct acpi_table_header > > *tboot_get_dmar_table(struct acpi_table_header *dmar_tb > >> return NULL; > >> > >> /* now map TXT heap */ > >> - heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE), > >> - *(u64 *)(config + TXTCR_HEAP_SIZE)); > >> + heap_base = ioremap(readl(config + TXTCR_HEAP_BASE), > >> + readl(config + TXTCR_HEAP_SIZE)); > >> iounmap(config); > >> if (!heap_base) > >> return NULL; > >> > >> /* walk heap to SinitMleData */ > >> /* skip BiosData */ > >> - heap_ptr = heap_base + *(u64 *)heap_base; > >> + heap_ptr = heap_base + readq(heap_base); > >> /* skip OsMleData */ > >> - heap_ptr += *(u64 *)heap_ptr; > >> + heap_ptr += readq(heap_ptr); > >> /* skip OsSinitData */ > >> - heap_ptr += *(u64 *)heap_ptr; > >> + heap_ptr += readq(heap_ptr); > >> /* now points to SinitMleDataSize; set to SinitMleData */ > >> heap_ptr += sizeof(u64); > >> /* get addr of DMAR table */ > >> - dmar_tbl = (struct acpi_table_header *)(heap_ptr + > >> - ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off - > >> - sizeof(u64)); > >> + dmar_tbl_off = readl(heap_ptr + SINIT_MLE_DATA_VTD_DMAR_OFF); > >> + memcpy_fromio(dmar_tbl, heap_ptr + dmar_tbl_off - sizeof(u64), > >> + sizeof(struct acpi_table_header)); > > > > That memcpy (or an equivalent of it) was not in the code before, AFAICS. > > > > How can this be an 'interface fix'? It adds in new code... > > > Sorry, current code only need to get addr of DMAR table, so memcpy_fromio may be removed, even though this will also work. > So "memcpy_fromio" line will be changed to > dmar_tbl = (struct acpi_table_header *)(heap_ptr + dmar_tbl_off + - sizeof(u64)); > If so, no new interface will be added, and the changelog at the beginning of this patch is engouch?
Please resubmit the fixed patch so I can have a fresh look.
Thanks,
Ingo
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