Kernel 5.8

[Skateman]

I also must confirm that Kernel 5.8 Alpha1 does not boot on my AmigaOne X5000

[xeno74]

I also must confirm that Kernel 5.8 Alpha1 does not boot on my AmigaOne X5000

Thanks for testing! I will bisect today.

[xeno74]

1. Code: Select all

   git bisect start

2. Code: Select all

   git bisect good 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162

   (Good: Linux 5.7)

3. Code: Select all

   git bisect bad 6929f71e46bdddbf1c4d67c2728648176c67c555

   (Bad: atomisp: avoid warning about unused function -- 2020-06-03 21:22:46 -0700)

   Code: Select all

   [ff45fc3ca0f3c38e752d75f71b8d8efcf409e42d] mm: simplify calling a compound page destructor

4. git bisect bad

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   [cfa3b8068b09f25037146bfd5eed041b78878bee] Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

5. git bisect bad

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   [17e0a7cb6a254c6d086562e7adf8b7ac24d267f3] Merge tag 'x86-cleanups-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

6. git bisect good

   Code: Select all

   [17839856fd588f4ab6b789f482ed3ffd7c403e1f] gup: document and work around "COW can break either way" issue

7. git bisect good

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   [c5d6c13843880ad0112f0513f3eb041b258be66e] Merge tag 'mmc-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc

8. git bisect bad

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   [94709049fb8442fb2f7b91fbec3c2897a75e18df] Merge branch 'akpm' (patches from Andrew)

9. git bisect bad

   Code: Select all

   [08d3090fc8dadd7b726dbda99d1baa39382c3f2c] mm/swapfile.c: simplify the calculation of n_goal

10. git bisect good

    Code: Select all

    [4926627793c0a7e7db2bc674e1d06777e86d8dab] mm: remove __get_vm_area

11. git bisect good

    Code: Select all

    [2b9059489c839e67ca9254913325e18cea11a980] mm: remove __vmalloc_node_flags_caller

12. git bisect good

    Code: Select all

    [6c0c7d2b365b21a413f6d75772a8a4a2c7d36916] mm/ioremap: track which page-table levels were modified

13. git bisect bad

    Code: Select all

    [cb0849a990b2928760bc38561e8d33b554196e25] powerpc: use __vmalloc_node in alloc_vm_stack

14. git bisect good

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    [d8626138009ba58ae2c22356966c2edaa1f1c3b5] mm: add functions to track page directory modifications

15. git bisect good

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    [2ba3e6947aed9bb9575eb1603c0ac6e39185d32a] mm/vmalloc: track which page-table levels were modified

16. git bisect bad

    Code: Select all

    2ba3e6947aed9bb9575eb1603c0ac6e39185d32a is the first bad commit
    commit 2ba3e6947aed9bb9575eb1603c0ac6e39185d32a
    Author: Joerg Roedel <[email protected]>
    Date:   Mon Jun 1 21:52:22 2020 -0700
    
        mm/vmalloc: track which page-table levels were modified
        
        Track at which levels in the page-table entries were modified by
        vmap/vunmap.
        
        After the page-table has been modified, use that information do decide
        whether the new arch_sync_kernel_mappings() needs to be called.
        
        [[email protected]: map_kernel_range_noflush() needs the arch_sync_kernel_mappings() call]
        Signed-off-by: Joerg Roedel <[email protected]>
        Signed-off-by: Andrew Morton <[email protected]>
        Acked-by: Andy Lutomirski <[email protected]>
        Acked-by: Peter Zijlstra (Intel) <[email protected]>
        Cc: Arnd Bergmann <[email protected]>
        Cc: Christoph Hellwig <[email protected]>
        Cc: Dave Hansen <[email protected]>
        Cc: "H . Peter Anvin" <[email protected]>
        Cc: Ingo Molnar <[email protected]>
        Cc: Matthew Wilcox (Oracle) <[email protected]>
        Cc: Michal Hocko <[email protected]>
        Cc: "Rafael J. Wysocki" <[email protected]>
        Cc: Steven Rostedt (VMware) <[email protected]>
        Cc: Thomas Gleixner <[email protected]>
        Cc: Vlastimil Babka <[email protected]>
        Link: http://lkml.kernel.org/r/[email protected]
        Signed-off-by: Linus Torvalds <[email protected]>
    
    :040000 040000 f6d8e1fc7b44c9e23aa419ac35911cc211cbf3cf 940c6a816e17a731da190c7173c88191e46b935f M	include
    :040000 040000 053ad50b6860da11900c014ce3723149cfdef6d5 56f75109266239b6c8704693105ab2b9222a4304 M	mm

The first bad commit is mm/vmalloc: track which page-table levels were modified.

[xeno74]

I was able to revert the commit mm/vmalloc: track which page-table levels were modified with the following command:

Code: Select all

git revert 2ba3e6947aed9bb9575eb1603c0ac6e39185d32a

Unfortunately it doesn't build.

Code: Select all

lib/ioremap.c: In function ‘ioremap_page_range’:
lib/ioremap.c:245:13: error: ‘ARCH_PAGE_TABLE_SYNC_MASK’ undeclared (first use in this function); did you mean ‘PROC_TABLE_TYPE_MASK’?
  if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
             ^~~~~~~~~~~~~~~~~~~~~~~~~
             PROC_TABLE_TYPE_MASK
lib/ioremap.c:245:13: note: each undeclared identifier is reported only once for each function it appears in
lib/ioremap.c:246:3: error: implicit declaration of function ‘arch_sync_kernel_mappings’ [-Werror=implicit-function-declaration]
   arch_sync_kernel_mappings(start, end);
   ^~~~~~~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
scripts/Makefile.build:266: recipe for target 'lib/ioremap.o' failed
make[1]: *** [lib/ioremap.o] Error 1
Makefile:1735: recipe for target 'lib' failed
make: *** [lib] Error 2
make: *** Auf noch nicht beendete Prozesse wird gewartet …
  AR      virt/lib/built-in.a
  AR      virt/built-in.a

[xeno74]

I commented out the following lines in the file lib/ioremap.c:

:245

Code: Select all

//if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
//              arch_sync_kernel_mappings(start, end);
//
//      return err;

After that I was able to compile the kernel. The kernel boots and works!!!!!!

[Skateman]

Great work!! Where is the kernel ...

[xeno74]

Great work!! Where is the kernel ...

Soon ...

If the kernel developers don’t create a patch then I will create a patch.

[xeno74]

I created a boot patch for solving the boot issues.

Code: Select all

diff -rupN a/include/linux/vmalloc.h b/include/linux/vmalloc.h
--- a/include/linux/vmalloc.h	2020-06-07 07:33:07.709630790 +0200
+++ b/include/linux/vmalloc.h	2020-06-07 07:31:03.565460991 +0200
@@ -132,22 +132,6 @@ extern int remap_vmalloc_range(struct vm
 							unsigned long pgoff);
 
 /*
- * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
- * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings()
- * needs to be called.
- */
-#ifndef ARCH_PAGE_TABLE_SYNC_MASK
-#define ARCH_PAGE_TABLE_SYNC_MASK 0
-#endif
-
-/*
- * There is no default implementation for arch_sync_kernel_mappings(). It is
- * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK
- * is 0.
- */
-void arch_sync_kernel_mappings(unsigned long start, unsigned long end);
-
-/*
  *	Lowlevel-APIs (not for driver use!)
  */
 
diff -rupN a/lib/ioremap.c b/lib/ioremap.c
--- a/lib/ioremap.c	2020-06-07 07:33:07.781630995 +0200
+++ b/lib/ioremap.c	2020-06-07 07:32:28.425463956 +0200
@@ -242,10 +242,6 @@ int ioremap_page_range(unsigned long add
 
 	flush_cache_vmap(start, end);
 
-	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
-		arch_sync_kernel_mappings(start, end);
-
-	return err;
 }
 
 #ifdef CONFIG_GENERIC_IOREMAP
diff -rupN a/mm/vmalloc.c b/mm/vmalloc.c
--- a/mm/vmalloc.c	2020-06-07 07:33:07.793631029 +0200
+++ b/mm/vmalloc.c	2020-06-07 07:31:03.565460991 +0200
@@ -69,8 +69,7 @@ static void free_work(struct work_struct
 
 /*** Page table manipulation functions ***/
 
-static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-			     pgtbl_mod_mask *mask)
+static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end)
 {
 	pte_t *pte;
 
@@ -79,81 +78,59 @@ static void vunmap_pte_range(pmd_t *pmd,
 		pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte);
 		WARN_ON(!pte_none(ptent) && !pte_present(ptent));
 	} while (pte++, addr += PAGE_SIZE, addr != end);
-	*mask |= PGTBL_PTE_MODIFIED;
 }
 
-static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
-			     pgtbl_mod_mask *mask)
+static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end)
 {
 	pmd_t *pmd;
 	unsigned long next;
-	int cleared;
 
 	pmd = pmd_offset(pud, addr);
 	do {
 		next = pmd_addr_end(addr, end);
-
-		cleared = pmd_clear_huge(pmd);
-		if (cleared || pmd_bad(*pmd))
-			*mask |= PGTBL_PMD_MODIFIED;
-
-		if (cleared)
+		if (pmd_clear_huge(pmd))
 			continue;
 		if (pmd_none_or_clear_bad(pmd))
 			continue;
-		vunmap_pte_range(pmd, addr, next, mask);
+		vunmap_pte_range(pmd, addr, next);
 	} while (pmd++, addr = next, addr != end);
 }
 
-static void vunmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
-			     pgtbl_mod_mask *mask)
+static void vunmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end)
 {
 	pud_t *pud;
 	unsigned long next;
-	int cleared;
 
 	pud = pud_offset(p4d, addr);
 	do {
 		next = pud_addr_end(addr, end);
-
-		cleared = pud_clear_huge(pud);
-		if (cleared || pud_bad(*pud))
-			*mask |= PGTBL_PUD_MODIFIED;
-
-		if (cleared)
+		if (pud_clear_huge(pud))
 			continue;
 		if (pud_none_or_clear_bad(pud))
 			continue;
-		vunmap_pmd_range(pud, addr, next, mask);
+		vunmap_pmd_range(pud, addr, next);
 	} while (pud++, addr = next, addr != end);
 }
 
-static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
-			     pgtbl_mod_mask *mask)
+static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end)
 {
 	p4d_t *p4d;
 	unsigned long next;
-	int cleared;
 
 	p4d = p4d_offset(pgd, addr);
 	do {
 		next = p4d_addr_end(addr, end);
-
-		cleared = p4d_clear_huge(p4d);
-		if (cleared || p4d_bad(*p4d))
-			*mask |= PGTBL_P4D_MODIFIED;
-
-		if (cleared)
+		if (p4d_clear_huge(p4d))
 			continue;
 		if (p4d_none_or_clear_bad(p4d))
 			continue;
-		vunmap_pud_range(p4d, addr, next, mask);
+		vunmap_pud_range(p4d, addr, next);
 	} while (p4d++, addr = next, addr != end);
 }
 
 /**
  * unmap_kernel_range_noflush - unmap kernel VM area
- * @start: start of the VM area to unmap
+ * @addr: start of the VM area to unmap
  * @size: size of the VM area to unmap
  *
  * Unmap PFN_UP(@size) pages at @addr.  The VM area @addr and @size specify
@@ -164,33 +141,24 @@ static void vunmap_p4d_range(pgd_t *pgd,
  * for calling flush_cache_vunmap() on to-be-mapped areas before calling this
  * function and flush_tlb_kernel_range() after.
  */
-void unmap_kernel_range_noflush(unsigned long start, unsigned long size)
+void unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
 {
-	unsigned long end = start + size;
+	unsigned long end = addr + size;
 	unsigned long next;
 	pgd_t *pgd;
-	unsigned long addr = start;
-	pgtbl_mod_mask mask = 0;
 
 	BUG_ON(addr >= end);
-	start = addr;
 	pgd = pgd_offset_k(addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		if (pgd_bad(*pgd))
-			mask |= PGTBL_PGD_MODIFIED;
 		if (pgd_none_or_clear_bad(pgd))
 			continue;
-		vunmap_p4d_range(pgd, addr, next, &mask);
+		vunmap_p4d_range(pgd, addr, next);
 	} while (pgd++, addr = next, addr != end);
-
-	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
-		arch_sync_kernel_mappings(start, end);
 }
 
 static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
-		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
-		pgtbl_mod_mask *mask)
+		unsigned long end, pgprot_t prot, struct page **pages, int *nr)
 {
 	pte_t *pte;
 
@@ -199,7 +167,7 @@ static int vmap_pte_range(pmd_t *pmd, un
 	 * callers keep track of where we're up to.
 	 */
 
-	pte = pte_alloc_kernel_track(pmd, addr, mask);
+	pte = pte_alloc_kernel(pmd, addr);
 	if (!pte)
 		return -ENOMEM;
 	do {
@@ -212,59 +180,55 @@ static int vmap_pte_range(pmd_t *pmd, un
 		set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
 		(*nr)++;
 	} while (pte++, addr += PAGE_SIZE, addr != end);
-	*mask |= PGTBL_PTE_MODIFIED;
 	return 0;
 }
 
 static int vmap_pmd_range(pud_t *pud, unsigned long addr,
-		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
-		pgtbl_mod_mask *mask)
+		unsigned long end, pgprot_t prot, struct page **pages, int *nr)
 {
 	pmd_t *pmd;
 	unsigned long next;
 
-	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
+	pmd = pmd_alloc(&init_mm, pud, addr);
 	if (!pmd)
 		return -ENOMEM;
 	do {
 		next = pmd_addr_end(addr, end);
-		if (vmap_pte_range(pmd, addr, next, prot, pages, nr, mask))
+		if (vmap_pte_range(pmd, addr, next, prot, pages, nr))
 			return -ENOMEM;
 	} while (pmd++, addr = next, addr != end);
 	return 0;
 }
 
 static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
-		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
-		pgtbl_mod_mask *mask)
+		unsigned long end, pgprot_t prot, struct page **pages, int *nr)
 {
 	pud_t *pud;
 	unsigned long next;
 
-	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
+	pud = pud_alloc(&init_mm, p4d, addr);
 	if (!pud)
 		return -ENOMEM;
 	do {
 		next = pud_addr_end(addr, end);
-		if (vmap_pmd_range(pud, addr, next, prot, pages, nr, mask))
+		if (vmap_pmd_range(pud, addr, next, prot, pages, nr))
 			return -ENOMEM;
 	} while (pud++, addr = next, addr != end);
 	return 0;
 }
 
 static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
-		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
-		pgtbl_mod_mask *mask)
+		unsigned long end, pgprot_t prot, struct page **pages, int *nr)
 {
 	p4d_t *p4d;
 	unsigned long next;
 
-	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
+	p4d = p4d_alloc(&init_mm, pgd, addr);
 	if (!p4d)
 		return -ENOMEM;
 	do {
 		next = p4d_addr_end(addr, end);
-		if (vmap_pud_range(p4d, addr, next, prot, pages, nr, mask))
+		if (vmap_pud_range(p4d, addr, next, prot, pages, nr))
 			return -ENOMEM;
 	} while (p4d++, addr = next, addr != end);
 	return 0;
@@ -291,28 +255,21 @@ static int vmap_p4d_range(pgd_t *pgd, un
 int map_kernel_range_noflush(unsigned long addr, unsigned long size,
 			     pgprot_t prot, struct page **pages)
 {
-	unsigned long start = addr;
 	unsigned long end = addr + size;
 	unsigned long next;
 	pgd_t *pgd;
 	int err = 0;
 	int nr = 0;
-	pgtbl_mod_mask mask = 0;
 
 	BUG_ON(addr >= end);
 	pgd = pgd_offset_k(addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		if (pgd_bad(*pgd))
-			mask |= PGTBL_PGD_MODIFIED;
-		err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
+		err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr);
 		if (err)
 			return err;
 	} while (pgd++, addr = next, addr != end);
 
-	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
-		arch_sync_kernel_mappings(start, end);
-
 	return 0;
 }

The X5000 boots but unfortunately the X1000 doesn't boot.

[xeno74]

Hi All,

The kernel developers have fixed the boot issue. The latest Git kernel boots on my X5000/40, X5000/20, and X1000.

I compiled the first alpha of kernel 5.8 again today.

New:

• PowerPC updates 5.8-1 (We don't need the mmu patch for the X1000 anymore)
• DMA mapping updates 5.8
• Linux 5.8 Graphics Updates Sent In With AMDGPU TMZ Support, P2P Buffers -- phoronix.com
• DRM updates
• Networking updates including dpaa updates
• KVM updates with PowerPC updates
• powerpc/mm: drop platform defined pmd_mknotpresent()
• powerpc: use __vmalloc_node in alloc_vm_stack
• powerpc: remove __ioremap_at and __iounmap_at
• powerpc: add an ioremap_phb helper (electra_cf)
• gpu/drm: remove the powerpc hack in drm_legacy_sg_alloc
• Bluetooth: Enable Microsoft extensions (BT_MSFTEXT)
• Linux Git log
• Phoronix articles, reviews and news stories covering Linux 5.8

Download: linux-image-5.8-alpha1-X1000_X5000.tar.gz



Please test it.

Thanks,
Christian

[Roland]

Alpha1 works with X5000/20 and Ubuntu 16! The onboard ethernet still needs the unplug/replug trick to work...