similar to: [added to the 3.18 stable tree] x86/mm/kmmio: Fix mmiotrace for hugepages

From: Karol Herbst <nouveau at karolherbst.de> This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit cfa52c0cfa4d727aa3e457bf29aeff296c528a08 ] Because Linux might use bigger pages than the 4K pages to handle those mmio ioremaps, the kmmio code shouldn't rely on the pade id as it currently does. Using the

4.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Karol Herbst <nouveau at karolherbst.de> commit cfa52c0cfa4d727aa3e457bf29aeff296c528a08 upstream. Because Linux might use bigger pages than the 4K pages to handle those mmio ioremaps, the kmmio code shouldn't rely on the pade id as it currently does. Using the memory address instead

4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Karol Herbst <nouveau at karolherbst.de> commit cfa52c0cfa4d727aa3e457bf29aeff296c528a08 upstream. Because Linux might use bigger pages than the 4K pages to handle those mmio ioremaps, the kmmio code shouldn't rely on the pade id as it currently does. Using the memory address instead

Because Linux might use bigger pages than the 4K pages to handle those mmio ioremaps, the kmmio code shouldn't rely on the pade id as it currently does. Using the memory address instead of the page id let's us lookup how big the page is and what it's base address is, so that we won't get a page fault within the same page twice anymore. I don't know if I got this right though,

Hi, I think I got mmiotracing back to work on my machine. Would you please test this patch on your machines too? I still got some UNKNOWN entries in the mmiotrace file, but besides that it seems to work. I have no idea if that's the right way though, and it needs a big cleanup, but I just wanted to see if the basic idea works the patch should apply just fine on any 4.4 kernel happy

Both call sites, that access kmmio_ctx, access kmmio_ctx with interrupts disabled. There is no need to use get_cpu_var() which additionally disables preemption. Use this_cpu_ptr() to access the kmmio_ctx variable of the current CPU. Signed-off-by: Sebastian Andrzej Siewior <bigeasy at linutronix.de> --- arch/x86/mm/kmmio.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)

If something calls ioremap with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but the entire page was armed for mmiotracing. On calling iounmap the address passed to unregister_kmmio_probe was PAGE_SIZE aligned by the caller leading to a complete freeze of the machine. We should always page

From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but the entire page was armed for mmiotracing. On calling iounmap() the address passed to

From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but the entire page was armed for mmiotracing. On calling iounmap() the address passed to

From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but the entire page was armed for mmiotracing. On calling iounmap() the address passed to

From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but the entire page was armed for mmiotracing. On calling iounmap() the address passed to

After every iounmap mmiotrace has to free kmmio_fault_pages, but it can't do it directly, so it defers freeing by RCU. It usually works, but when mmiotraced code calls ioremap-iounmap multiple times without sleeping between (so RCU won't kick in and start freeing) it can be given the same virtual address, so at every iounmap mmiotrace will schedule the same pages for release. Obviously it

4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but

3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but

4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but

4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Karol Herbst <kherbst at redhat.com> [ Upstream commit 6d60ce384d1d5ca32b595244db4077a419acc687 ] If something calls ioremap() with an address not aligned to PAGE_SIZE, the returned address might be not aligned as well. This led to a probe registered on exactly the returned address, but

After every iounmap mmiotrace has to free kmmio_fault_pages, but it can't do it directly, so it defers freeing by RCU. It usually works, but when mmiotraced code calls ioremap-iounmap multiple times without sleeping between (so RCU won't kick in and start freeing) it can be given the same virtual address, so at every iounmap mmiotrace will schedule the same pages for release. Obviously it

Hi Linus, The following changes since commit 540ad6b62b3a188a53b51cac81d8a60d40e29fbd: Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb (2010-07-28 20:01:26 -0700) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git x86-mm-for-linus Andres Salomon (1): x86, mm: Create

add_kmmio_fault_page using -1 instead of the -ENOMEM defined macro to specify kmmio_fault_page allocation failed. Smatch tool warning: arch/x86/mm/kmmio.c:389 add_kmmio_fault_page() warn: returning -1 instead of -ENOMEM is sloppy Signed-off-by: Vasyl Gomonovych <gomonovych at gmail.com> --- arch/x86/mm/kmmio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git

To enable eventual removal of pr_warning This makes pr_warn use consistent for arch/x86 Prior to this patch, there were 46 uses of pr_warning and 122 uses of pr_warn in arch/x86 Miscellanea: o Coalesce a few formats and realign arguments o Convert a couple of multiple line printks to single line Signed-off-by: Joe Perches <joe at perches.com> --- arch/x86/kernel/amd_gart_64.c