| Message ID | 20210518064215.2856977-2-tientzu@chromium.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Restricted DMA | expand |
On 5/17/2021 11:42 PM, Claire Chang wrote: > Add a new function, swiotlb_init_io_tlb_mem, for the io_tlb_mem struct > initialization to make the code reusable. > > Note that we now also call set_memory_decrypted in swiotlb_init_with_tbl. > > Signed-off-by: Claire Chang <tientzu@chromium.org> > --- > kernel/dma/swiotlb.c | 51 ++++++++++++++++++++++---------------------- > 1 file changed, 25 insertions(+), 26 deletions(-) > > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c > index 8ca7d505d61c..d3232fc19385 100644 > --- a/kernel/dma/swiotlb.c > +++ b/kernel/dma/swiotlb.c > @@ -168,9 +168,30 @@ void __init swiotlb_update_mem_attributes(void) > memset(vaddr, 0, bytes); > } > > -int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) > +static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start, > + unsigned long nslabs, bool late_alloc) > { > + void *vaddr = phys_to_virt(start); > unsigned long bytes = nslabs << IO_TLB_SHIFT, i; > + > + mem->nslabs = nslabs; > + mem->start = start; > + mem->end = mem->start + bytes; > + mem->index = 0; > + mem->late_alloc = late_alloc; > + spin_lock_init(&mem->lock); > + for (i = 0; i < mem->nslabs; i++) { > + mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); > + mem->slots[i].orig_addr = INVALID_PHYS_ADDR; > + mem->slots[i].alloc_size = 0; > + } > + > + set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); > + memset(vaddr, 0, bytes); You are doing an unconditional set_memory_decrypted() followed by a memset here, and then: > +} > + > +int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) > +{ > struct io_tlb_mem *mem; > size_t alloc_size; > > @@ -186,16 +207,8 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) > if (!mem) > panic("%s: Failed to allocate %zu bytes align=0x%lx\n", > __func__, alloc_size, PAGE_SIZE); > - mem->nslabs = nslabs; > - mem->start = __pa(tlb); > - mem->end = mem->start + bytes; > - mem->index = 0; > - spin_lock_init(&mem->lock); > - for (i = 0; i < mem->nslabs; i++) { > - mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); > - mem->slots[i].orig_addr = INVALID_PHYS_ADDR; > - mem->slots[i].alloc_size = 0; > - } > + > + swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false); You convert this call site with swiotlb_init_io_tlb_mem() which did not do the set_memory_decrypted()+memset(). Is this okay or should swiotlb_init_io_tlb_mem() add an additional argument to do this conditionally?
On Thu, May 20, 2021 at 2:50 AM Florian Fainelli <f.fainelli@gmail.com> wrote: > > > > On 5/17/2021 11:42 PM, Claire Chang wrote: > > Add a new function, swiotlb_init_io_tlb_mem, for the io_tlb_mem struct > > initialization to make the code reusable. > > > > Note that we now also call set_memory_decrypted in swiotlb_init_with_tbl. > > > > Signed-off-by: Claire Chang <tientzu@chromium.org> > > --- > > kernel/dma/swiotlb.c | 51 ++++++++++++++++++++++---------------------- > > 1 file changed, 25 insertions(+), 26 deletions(-) > > > > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c > > index 8ca7d505d61c..d3232fc19385 100644 > > --- a/kernel/dma/swiotlb.c > > +++ b/kernel/dma/swiotlb.c > > @@ -168,9 +168,30 @@ void __init swiotlb_update_mem_attributes(void) > > memset(vaddr, 0, bytes); > > } > > > > -int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) > > +static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start, > > + unsigned long nslabs, bool late_alloc) > > { > > + void *vaddr = phys_to_virt(start); > > unsigned long bytes = nslabs << IO_TLB_SHIFT, i; > > + > > + mem->nslabs = nslabs; > > + mem->start = start; > > + mem->end = mem->start + bytes; > > + mem->index = 0; > > + mem->late_alloc = late_alloc; > > + spin_lock_init(&mem->lock); > > + for (i = 0; i < mem->nslabs; i++) { > > + mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); > > + mem->slots[i].orig_addr = INVALID_PHYS_ADDR; > > + mem->slots[i].alloc_size = 0; > > + } > > + > > + set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); > > + memset(vaddr, 0, bytes); > > You are doing an unconditional set_memory_decrypted() followed by a > memset here, and then: > > > +} > > + > > +int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) > > +{ > > struct io_tlb_mem *mem; > > size_t alloc_size; > > > > @@ -186,16 +207,8 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) > > if (!mem) > > panic("%s: Failed to allocate %zu bytes align=0x%lx\n", > > __func__, alloc_size, PAGE_SIZE); > > - mem->nslabs = nslabs; > > - mem->start = __pa(tlb); > > - mem->end = mem->start + bytes; > > - mem->index = 0; > > - spin_lock_init(&mem->lock); > > - for (i = 0; i < mem->nslabs; i++) { > > - mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); > > - mem->slots[i].orig_addr = INVALID_PHYS_ADDR; > > - mem->slots[i].alloc_size = 0; > > - } > > + > > + swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false); > > You convert this call site with swiotlb_init_io_tlb_mem() which did not > do the set_memory_decrypted()+memset(). Is this okay or should > swiotlb_init_io_tlb_mem() add an additional argument to do this > conditionally? I'm actually not sure if this it okay. If not, will add an additional argument for it. > -- > Florian
> > do the set_memory_decrypted()+memset(). Is this okay or should > > swiotlb_init_io_tlb_mem() add an additional argument to do this > > conditionally? > > I'm actually not sure if this it okay. If not, will add an additional > argument for it. Any observations discovered? (Want to make sure my memory-cache has the correct semantics for set_memory_decrypted in mind). > > > -- > > Florian
On Mon, May 24, 2021 at 11:53 PM Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> wrote: > > > > do the set_memory_decrypted()+memset(). Is this okay or should > > > swiotlb_init_io_tlb_mem() add an additional argument to do this > > > conditionally? > > > > I'm actually not sure if this it okay. If not, will add an additional > > argument for it. > > Any observations discovered? (Want to make sure my memory-cache has the > correct semantics for set_memory_decrypted in mind). It works fine on my arm64 device. > > > > > -- > > > Florian
On Wed, May 19, 2021 at 11:50:07AM -0700, Florian Fainelli wrote: > You convert this call site with swiotlb_init_io_tlb_mem() which did not > do the set_memory_decrypted()+memset(). Is this okay or should > swiotlb_init_io_tlb_mem() add an additional argument to do this > conditionally? The zeroing is useful and was missing before. I think having a clean state here is the right thing. Not sure about the set_memory_decrypted, swiotlb_update_mem_attributes kinda suggests it is too early to set the memory decrupted. Adding Tom who should now about all this.
On 5/27/21 8:02 AM, Christoph Hellwig wrote: > On Wed, May 19, 2021 at 11:50:07AM -0700, Florian Fainelli wrote: >> You convert this call site with swiotlb_init_io_tlb_mem() which did not >> do the set_memory_decrypted()+memset(). Is this okay or should >> swiotlb_init_io_tlb_mem() add an additional argument to do this >> conditionally? > > The zeroing is useful and was missing before. I think having a clean > state here is the right thing. > > Not sure about the set_memory_decrypted, swiotlb_update_mem_attributes > kinda suggests it is too early to set the memory decrupted. > > Adding Tom who should now about all this. The reason for adding swiotlb_update_mem_attributes() was because having the call to set_memory_decrypted() in swiotlb_init_with_tbl() triggered a BUG_ON() related to interrupts not being enabled yet during boot. So that call had to be delayed until interrupts were enabled. Thanks, Tom >
On 5/27/21 9:41 AM, Tom Lendacky wrote: > On 5/27/21 8:02 AM, Christoph Hellwig wrote: >> On Wed, May 19, 2021 at 11:50:07AM -0700, Florian Fainelli wrote: >>> You convert this call site with swiotlb_init_io_tlb_mem() which did not >>> do the set_memory_decrypted()+memset(). Is this okay or should >>> swiotlb_init_io_tlb_mem() add an additional argument to do this >>> conditionally? >> >> The zeroing is useful and was missing before. I think having a clean >> state here is the right thing. >> >> Not sure about the set_memory_decrypted, swiotlb_update_mem_attributes >> kinda suggests it is too early to set the memory decrupted. >> >> Adding Tom who should now about all this. > > The reason for adding swiotlb_update_mem_attributes() was because having > the call to set_memory_decrypted() in swiotlb_init_with_tbl() triggered a > BUG_ON() related to interrupts not being enabled yet during boot. So that > call had to be delayed until interrupts were enabled. I pulled down and tested the patch set and booted with SME enabled. The following was seen during the boot: [ 0.134184] BUG: Bad page state in process swapper pfn:108002 [ 0.134196] page:(____ptrval____) refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x108002 [ 0.134201] flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff) [ 0.134208] raw: 0017ffffc0000000 ffff88847f355e28 ffff88847f355e28 0000000000000000 [ 0.134210] raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000 [ 0.134212] page dumped because: nonzero mapcount [ 0.134213] Modules linked in: [ 0.134218] CPU: 0 PID: 0 Comm: swapper Not tainted 5.13.0-rc2-sos-custom #3 [ 0.134221] Hardware name: ... [ 0.134224] Call Trace: [ 0.134233] dump_stack+0x76/0x94 [ 0.134244] bad_page+0xa6/0xf0 [ 0.134252] __free_pages_ok+0x331/0x360 [ 0.134256] memblock_free_all+0x158/0x1c1 [ 0.134267] mem_init+0x1f/0x14c [ 0.134273] start_kernel+0x290/0x574 [ 0.134279] secondary_startup_64_no_verify+0xb0/0xbb I see this about 40 times during the boot, each with a different PFN. The system boots (which seemed odd), but I don't know if there will be side effects to this (I didn't stress the system). I modified the code to add a flag to not do the set_memory_decrypted(), as suggested by Florian, when invoked from swiotlb_init_with_tbl(), and that eliminated the bad page state BUG. Thanks, Tom > > Thanks, > Tom > >>
On Fri, May 28, 2021 at 12:32 AM Tom Lendacky <thomas.lendacky@amd.com> wrote: > > On 5/27/21 9:41 AM, Tom Lendacky wrote: > > On 5/27/21 8:02 AM, Christoph Hellwig wrote: > >> On Wed, May 19, 2021 at 11:50:07AM -0700, Florian Fainelli wrote: > >>> You convert this call site with swiotlb_init_io_tlb_mem() which did not > >>> do the set_memory_decrypted()+memset(). Is this okay or should > >>> swiotlb_init_io_tlb_mem() add an additional argument to do this > >>> conditionally? > >> > >> The zeroing is useful and was missing before. I think having a clean > >> state here is the right thing. > >> > >> Not sure about the set_memory_decrypted, swiotlb_update_mem_attributes > >> kinda suggests it is too early to set the memory decrupted. > >> > >> Adding Tom who should now about all this. > > > > The reason for adding swiotlb_update_mem_attributes() was because having > > the call to set_memory_decrypted() in swiotlb_init_with_tbl() triggered a > > BUG_ON() related to interrupts not being enabled yet during boot. So that > > call had to be delayed until interrupts were enabled. > > I pulled down and tested the patch set and booted with SME enabled. The > following was seen during the boot: > > [ 0.134184] BUG: Bad page state in process swapper pfn:108002 > [ 0.134196] page:(____ptrval____) refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x108002 > [ 0.134201] flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff) > [ 0.134208] raw: 0017ffffc0000000 ffff88847f355e28 ffff88847f355e28 0000000000000000 > [ 0.134210] raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000 > [ 0.134212] page dumped because: nonzero mapcount > [ 0.134213] Modules linked in: > [ 0.134218] CPU: 0 PID: 0 Comm: swapper Not tainted 5.13.0-rc2-sos-custom #3 > [ 0.134221] Hardware name: ... > [ 0.134224] Call Trace: > [ 0.134233] dump_stack+0x76/0x94 > [ 0.134244] bad_page+0xa6/0xf0 > [ 0.134252] __free_pages_ok+0x331/0x360 > [ 0.134256] memblock_free_all+0x158/0x1c1 > [ 0.134267] mem_init+0x1f/0x14c > [ 0.134273] start_kernel+0x290/0x574 > [ 0.134279] secondary_startup_64_no_verify+0xb0/0xbb > > I see this about 40 times during the boot, each with a different PFN. The > system boots (which seemed odd), but I don't know if there will be side > effects to this (I didn't stress the system). > > I modified the code to add a flag to not do the set_memory_decrypted(), as > suggested by Florian, when invoked from swiotlb_init_with_tbl(), and that > eliminated the bad page state BUG. Thanks. Will add a flag to skip set_memory_decrypted() in v9. > > Thanks, > Tom > > > > > Thanks, > > Tom > > > >>
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 8ca7d505d61c..d3232fc19385 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -168,9 +168,30 @@ void __init swiotlb_update_mem_attributes(void) memset(vaddr, 0, bytes); } -int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) +static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start, + unsigned long nslabs, bool late_alloc) { + void *vaddr = phys_to_virt(start); unsigned long bytes = nslabs << IO_TLB_SHIFT, i; + + mem->nslabs = nslabs; + mem->start = start; + mem->end = mem->start + bytes; + mem->index = 0; + mem->late_alloc = late_alloc; + spin_lock_init(&mem->lock); + for (i = 0; i < mem->nslabs; i++) { + mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); + mem->slots[i].orig_addr = INVALID_PHYS_ADDR; + mem->slots[i].alloc_size = 0; + } + + set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); + memset(vaddr, 0, bytes); +} + +int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) +{ struct io_tlb_mem *mem; size_t alloc_size; @@ -186,16 +207,8 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) if (!mem) panic("%s: Failed to allocate %zu bytes align=0x%lx\n", __func__, alloc_size, PAGE_SIZE); - mem->nslabs = nslabs; - mem->start = __pa(tlb); - mem->end = mem->start + bytes; - mem->index = 0; - spin_lock_init(&mem->lock); - for (i = 0; i < mem->nslabs; i++) { - mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); - mem->slots[i].orig_addr = INVALID_PHYS_ADDR; - mem->slots[i].alloc_size = 0; - } + + swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false); io_tlb_default_mem = mem; if (verbose) @@ -282,7 +295,6 @@ swiotlb_late_init_with_default_size(size_t default_size) int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) { - unsigned long bytes = nslabs << IO_TLB_SHIFT, i; struct io_tlb_mem *mem; if (swiotlb_force == SWIOTLB_NO_FORCE) @@ -297,20 +309,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) if (!mem) return -ENOMEM; - mem->nslabs = nslabs; - mem->start = virt_to_phys(tlb); - mem->end = mem->start + bytes; - mem->index = 0; - mem->late_alloc = 1; - spin_lock_init(&mem->lock); - for (i = 0; i < mem->nslabs; i++) { - mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i); - mem->slots[i].orig_addr = INVALID_PHYS_ADDR; - mem->slots[i].alloc_size = 0; - } - - set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT); - memset(tlb, 0, bytes); + swiotlb_init_io_tlb_mem(mem, virt_to_phys(tlb), nslabs, true); io_tlb_default_mem = mem; swiotlb_print_info();
Add a new function, swiotlb_init_io_tlb_mem, for the io_tlb_mem struct initialization to make the code reusable. Note that we now also call set_memory_decrypted in swiotlb_init_with_tbl. Signed-off-by: Claire Chang <tientzu@chromium.org> --- kernel/dma/swiotlb.c | 51 ++++++++++++++++++++++---------------------- 1 file changed, 25 insertions(+), 26 deletions(-)