| Message ID | 1423087236.22217.11.camel@theros.lm.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Feb 4, 2015 at 2:00 PM, Ross Zwisler <ross.zwisler@linux.intel.com> wrote: > On Wed, 2015-02-04 at 13:45 -0800, Roger C. Pao (Enmotus) wrote: > > [rcpao@test27 pmem]$ sudo modprobe pmem map=4G@18G > > modprobe: ERROR: could not insert 'pmem': Invalid argument > > > > > > From dmesg: > > > > [ 125.343206] add_persistent_memory: request_mem_region_exclusive > > phys=0x480000000 size=0x100000000 failed > > > > > > occurs even if I add mapmem=4G$18G to the kernel line. I originally > > tried without it. > > > > [rcpao@test27 pmem]$ cat /proc/cmdline > > BOOT_IMAGE=/vmlinuz-3.19.0-rc3+ root=/dev/mapper/fedora-root ro > > rd.lvm.lv=fedora/swap rd.lvm.lv=fedora/root mapmem=4G$18G > > > > > > Note: /etc/default/grub requires \\\ to escape \ and $: > > GRUB_CMDLINE_LINUX="rd.lvm.lv=fedora/swap rd.lvm.lv=fedora/root > > mapmem=4G\\\$18G" > > Ah, yep, I've seen this issue as well I think. The > request_mem_region_exclusive() fails when you aren't dealing with kernel > usable memory - and yours isn't because it's marked as type 12 in the e820 > table. > > Here, try this patch (compile tested only against my tree): > > ------------------------- > > From 9dbd5ae0b7369862e71d28e465372b75cd363e9c Mon Sep 17 00:00:00 2001 > From: Ross Zwisler <ross.zwisler@linux.intel.com> > Date: Wed, 4 Feb 2015 14:58:43 -0700 > Subject: [PATCH] TEST pmem: Skip memory reservation for PMEM region > > Skip the memory reservation step for the memory consumed by PMEM. This > is a quick workaround for systems that have real NVDIMMs that don't show > up as kernel usable in the e820 table. > > Compile tested only. > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> > --- > drivers/block/pmem.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c > index 1bd9ab0..078ad09 100644 > --- a/drivers/block/pmem.c > +++ b/drivers/block/pmem.c > @@ -238,6 +238,7 @@ int pmem_mapmem(struct pmem_device *pmem) > struct resource *res_mem; > int err; > > + /* > res_mem = request_mem_region_exclusive(pmem->phys_addr, pmem->size, > "pmem"); > if (!res_mem) { > @@ -245,6 +246,7 @@ int pmem_mapmem(struct pmem_device *pmem) > pmem->phys_addr, pmem->size); > return -EINVAL; > } > + */ > > pmem->virt_addr = ioremap_cache(pmem->phys_addr, pmem->size); > if (unlikely(!pmem->virt_addr)) { > @@ -254,7 +256,7 @@ int pmem_mapmem(struct pmem_device *pmem) > return 0; > > out_release: > - release_mem_region(pmem->phys_addr, pmem->size); > +// release_mem_region(pmem->phys_addr, pmem->size); > return err; > } > > @@ -264,7 +266,7 @@ void pmem_unmapmem(struct pmem_device *pmem) > return; > > iounmap(pmem->virt_addr); > - release_mem_region(pmem->phys_addr, pmem->size); > +// release_mem_region(pmem->phys_addr, pmem->size); > pmem->virt_addr = NULL; > } > > -- > 1.9.3 > > Success! Thank you Ross. Your patch works with a small compiler warning: CC [M] drivers/block/pmem.o drivers/block/pmem.c: In function ‘pmem_mapmem’: drivers/block/pmem.c:238:19: warning: unused variable ‘res_mem’ [-Wunused-variable] struct resource *res_mem; ^ ... [rcpao@test27 ~]$ sudo modprobe pmem pmem_start_gb=18 pmem_size_gb=4 pmem_count=1 [rcpao@test27 ~]$ ls -al /dev/pmem0 brw-rw----. 1 root disk 259, 0 Feb 4 14:46 /dev/pmem0 dmesg: [ 135.047433] pmem0: unknown partition table [ 135.047563] pmem: module loaded [ 135.047433] pmem0: unknown partition table <<<--- expected at this point. I plan on using this directly so I hope nothing attempts to use it--not sure why anything is even looking for a partition table in it. At least now I can continue with my NVDIMM testing using your prd tree plus this patch. Thank you.
diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c index 1bd9ab0..078ad09 100644 --- a/drivers/block/pmem.c +++ b/drivers/block/pmem.c @@ -238,6 +238,7 @@ int pmem_mapmem(struct pmem_device *pmem) struct resource *res_mem; int err; + /* res_mem = request_mem_region_exclusive(pmem->phys_addr, pmem->size, "pmem"); if (!res_mem) { @@ -245,6 +246,7 @@ int pmem_mapmem(struct pmem_device *pmem) pmem->phys_addr, pmem->size); return -EINVAL; } + */ pmem->virt_addr = ioremap_cache(pmem->phys_addr, pmem->size); if (unlikely(!pmem->virt_addr)) { @@ -254,7 +256,7 @@ int pmem_mapmem(struct pmem_device *pmem) return 0; out_release: - release_mem_region(pmem->phys_addr, pmem->size); +// release_mem_region(pmem->phys_addr, pmem->size); return err; } @@ -264,7 +266,7 @@ void pmem_unmapmem(struct pmem_device *pmem) return; iounmap(pmem->virt_addr); - release_mem_region(pmem->phys_addr, pmem->size); +// release_mem_region(pmem->phys_addr, pmem->size); pmem->virt_addr = NULL; }